SUPER PRECISION BEARINGS

Transcription

1 SUPER PRECISION BEARINGS

2 Intoduction As technologies evolve, all manufactues shae a global esponsibility to espect and potect the envionment. NSK Motion and Contol poducts eflect ou copoate commitment to envionmental esponsibility. While ou poducts impove the pefomance of machines in a vaiety of industies, they also save enegy and conseve esouces because of ou supeio pecision machining technologies. To meet the needs of the highly specialized machine tool industy, we have enhanced each and evey aspect of ou R&D capabilities at ou Technology Centes. Theefoe, NSK s pecision beaings ae used in a wide vaiety of industies, such as semiconducto poduction and industial obots, and have eaned a eputation fo excellent pefomance. Today, NSK manufactues highly accuate, eliable pecision beaings in Japan and Euope and supplies them all ove the wold. This catalog explains technical mateials including ou latest eseach and expeimental data, vaious applications, the types of pecision beaings available, and the pope utilization of each specific type of NSK s pecision beaing. 1

3 Table of Contents Pat1 Pat 2 Pat 3 Pat 4 Pat 5 Pat 6 Pat 7 Pat 8 Pat1. NSK Supe Pecision Beaings Global Suppot Capabilities Development Capabilities Quality Contol and Poduction Capabilities Pat2. Featues of Pecision Beaings Metallugical Technology to Extend Beaing Life Ceamic Rolling Elements Cages Beaing Components Poduct Range Pefomance of Each Beaing Type Pat3. Selecting the Right Beaing is Citical Beaing Selection Typical High-Speed Main Shaft Spindle Stuctues Othe Spindle Stuctues Featues of Angula Contact Ball Beaings Featues of Cylindical Rolle Beaings P6 P8 P10 P14 P16 P18 P20 P22 P24 P36 P38 P40 P42 P44 Pat4. Beaing Types 1. Angula Contact Ball Beaings High Pecision Angula Contact Ball Beaings (Standad Seies) P48-60 Featues Numbeing System Beaing Tables Miniatue Seies, BSA Seies fo Ball Scew Suppot 79 Seies 70 Seies 72 Seies Ulta High-Speed Angula Contact Ball Beaings (ROBUST Seies) P62-79 Featues Numbeing System Beaing Tables BNR19, BER19 Seies BNR10, BER10 Seies BNR19XE/10XE, BER19XE/10XE Seies (Spinshot II) BNR29, BER29 Seies (Wide Seies) BNR20, BER20 Seies (Wide Seies) Ulta High Pecision Angula Contact Ball Beaings (ROBUST Seies BGR) P80-84 Featues Numbeing System Beaing Tables BGR19 Seies BGR10 Seies BGR02 Seies 2. Cylindical Rolle Beaings Cylindical Rolle Beaings P88-97 Featues Numbeing System Beaing Tables Double-Row Cylindical Rolle Beaings (High Rigidity Seies) 30 Seies 39 Seies 49 Seies Single-Row Cylindical Rolle Beaings (Standad Seies) 10 Seies Ulta High-Speed Single-Row Cylindical Rolle Beaings (ROBUST Seies) 10 Seies Double-Row Cylindical Rolle Beaings (Low Heat Geneation Seies) 30 Seies Ulta High-Speed Single-Row Cylindical Rolle Beaings (Low Heat Geneation Seies) 10 Seies 5. Pecision Deep Goove Ball Beaings Pecision Deep Goove Ball Beaings P Featues Numbeing System Beaing Tables T1X Type (Polyamide esin cage) 60, 62 and 63 Seies 6. Peipheal Equipment Gauges P GR Gauges Featues Numbeing System GTR Gauges Featues Numbeing System GN Gauges Featues Numbeing System Beaing Monito P128 Beaing Heate P129 Gease Replenishing System P Oil-Ai Lubicato P Sealed Pecision Spaces fo Machine Tool Spindles P Pat5. Technical Guide 1. Life P Rolling Fatigue Life and Basic Load Rating New Life Theoy 2. Static Load Ratings and Static Equivalent Loads P Angula Contact Ball Beaing Combinations P Featues of Each Combination Univesal Combination 4. Peload and Rigidity P Types of Peload and Rigidity Peload and Rigidity Tables 5. Limiting Speeds P Lubication P Pat6. Beaing Handling 1. Mounting P Cleaning the Beaings and Related Pats 2. Checking Dimensions of Related Pats 3. Mounting Pocedues 4. Inspection afte Mounting 2. Opeational Inspection P Initial Running-in Pocedues P Pat7. Beaing Failue Diagnosis 1. Beaing Failue and Countemeasue P Diagnosis with Sound and Vibation P Pat8. Appendices Toleances fo Shaft Diametes P Toleances fo Housing Boe Diametes P Values of Standad Toleances fo IT Gades P Hadness Convesion Table P234 Physical and Mechanical Popeties of Mateial P Old and New Numbe Contast Table P237 Method fo Measuing Axial Cleaance of Combined Angula Contact Ball Beaings P238 Request fo Specification Investigation P Angula Contact Thust Ball Beaings Angula Contact Thust Ball Beaings P Featues Numbeing System Beaing Tables High-Speed Angula Contact Thust Ball Beaings (ROBUST Seies) BAR10 Seies BTR10 Seies Double-Diection Angula Contact Thust Ball Beaings (TAC Seies) TAC29D Seies TAC20D Seies 4. Ball Scew Suppot Beaings Angula Contact Thust Ball Beaings fo Ball Scew Suppot P Featues Numbeing System Beaing Tables Machine Tool Applications TAC B Seies Electic Injection Molding Machine Applications TAC02 and 03 Seies Units fo Ball Scew Suppot P Featues Numbeing System Beaing Tables 7. Beaing Toleances P Toleance fo Radial Beaings Toleances fo Tapeed Boes Toleances fo Angula Contact Thust Ball Beaings 8. Designing of Shafts and Housings P Fitting of Shafts and Housings Shafts and Housing Toleance Shoulde and Fillet Dimensions Chamfe Dimensions 9. Spaces P Space Dimensions Position of Spay Nozzle 2 3

4 SUPER PRECISION BEARINGS Pat1 Contents Pat1. NSK Supe Pecision Beaings Global Suppot Capabilities P6 Development Capabilities P8 Quality Contol and Poduction Capabilities P10 4 5

5 Global Suppot Capabilities Pat1 Pat 2 Pat 3 Pat 4 Pat 5 Pat 6 Pat 7 Pat 8 Unifom suppot system anywhee in the wold NSK is committed to manufactuing and selling poducts with consistently high quality anywhee in the wold unde the leadeship of Technology Centes in the fou majo global makets. NSK s sales offices, with expet staff that constantly exploe custome needs, pomote global netwok management that encompasses Technology Centes as well as poduction sites. NSK can espond quickly and effectively to the vaious needs of customes and suppots thei business development effots in any egion. China Technology Cente Euope Asia Japan 77 4 Head Office Building NSK Fujisawa Plant The Ameicas Fujisawa Technology Cente Headquates Newak Plant Euope Technology Cente Asia Pacific Technology Cente Ameican Technology Cente Sales office, Plant Technical office Global netwok management povides optimal, high-quality poducts Technology Cente custome suppot Custom poducts fo unique custome applications Ou global suppot netwok is available wheeve ou customes ae located NSK has established a highly-developed infomation netwok centeed on Technology Centes located in the fou majo makets of the wold Euope, the United States, Asia and Japan. With this netwok, we ae able to gathe infomation, in eal time, elated to the changes and tends in any maket in the wold. As a esult, we can eact quickly to meet changing custome needs to supply optimal, high-quality poducts. Infomation system diectly linked to customes Technology Centes in fou majo makets povide technical suppot to customes in thei espective egions. This suppot enables ou customes to use NSK s poducts unde ideal conditions and achieve the best possible pefomance. Each Technology Cente woks closely with ou customes to detemine thei pecise application needs. In doing so, we assist them in identifying the ight NSK poduct fo each application to ealize maximum efficiency and cost effectiveness. Upon equest, we can also supply completely customized poducts to satisfy highly-specialized custome needs. Ou extensive global netwok is able to eceive odes and supply poducts anywhee in the wold. NSK s distibutos cove the globe and maintain an inventoy of all citical poducts in evey majo maket and location, making it possible to supply poducts to customes without delay. NSK also povides technical suppot woldwide to help customes detemine the best beaing fo each application, espond quickly to any questions, and immediately addess any poblems ou customes may encounte

6 Development Capabilities Pat1 Pat 2 Pat 3 Pat 4 Pat 5 Pat 6 Pat 7 Pat 8 NSK s key technology NSK s key technology is Tibology, the science of fiction and wea. Tibology is a technology that focuses on saving enegy and conseving esouces by educing fiction and wea as well as peventing machine failue and theeby inceasing eliability. With tibology positioned at its coe, NSK will futhe expand its fou key technologies: analysis technology fo thooughly eliminating enegy losses; evaluation technology fo ensuing exacting esponsiveness to maket needs; lubication technology fo educing enegy losses and enhancing functionality; and mateial technology fo extending poduct life, and will foge ahead in the development of envionmentally fiendly poducts based on the foundation of these technologies. Analysis Technology NSK developed its own softwae, BRAIN (Beaing Analysis In NSK), which enables digital simulations of fiction-elated movement and pefomance by applying Tibology. The combined use of this simulation data with an effective facto method (EFM) ealizes advanced compute-aided engineeing (CAE). Lubication Technology Though the elentless application of Tibology, NSK s key technology, NSK has pusued lubication technologies that allow machines to delive maximum pefomance and NSK s accomplishments in these effots contibute to saving enegy and esouces, theeby conseving the global envionment. Evaluation Technology NSK has established an evaluation technology that spans a wide ange of applications by employing advanced technologies such as nano-ode unout measuement using ulta high-pecision measuing instuments. Ou evaluation technology contibutes to the development of cutting-edge poducts that coespond with inceasingly sophisticated maket needs. Mateial Technology Reseach and development acoss a wide ange of mateial technologies has been conducted to poduce eve-highe pefoming poducts. Poducts made of NSK s popietay mateials delive long life unde hash conditions, ae maintenance-fee, and also suppot all industies. 8 9

7 Quality Contol and Poduction Capabilities Pat1 Pat 2 Pat 3 Pat 4 Pat 5 Pat 6 Pat 7 Pat 8 The highest level of quality in the wold NSK pecision beaings delive the highest level of accuacy, suppoted by ou poduction capability, state-of-the-at equipment and extensive manufactuing expetise, as well as ou commitment to applying the same igoous quality contol pocedues at each stage of the poduction pocess in evey NSK facility. NSK focuses its effots at its global poduction sites in Japan and England on offeing poducts with high accuacy to quickly meet the divese needs of customes woldwide. 1 Heat teatment 2 Ginding 3 Component inspection 4 5 Finished Assembly goods inspection 6 Packaging Manufactuing technologies to poduce high accuacy poducts To maintain ou eputation fo manufactuing pecision beaings with the highest degee of accuacy in the wold, all pecision beaings ae checked to nanomete accuacy. Global poduction in England and Japan NSK s pecision beaings ae made in both England and Japan. The combined expetise and locations of these manufactuing facilities allow us to meet evey custome need. NSK Newak Plant NSK Fujisawa Plant NSK symbol NSK s golden box guaantees the highest level of accuacy. Complete quality contol and envionmental esponsibility As membes of an ISO 9001-cetified entepise, all NSK plants adhee to stict intenational standads fo quality contol. NSK is also making an all-out, companywide effot to addess envionmental concens as a top pioity. ISO 9001 Cetification ISO Cetification 10 11

8 High Pefomance in the Next Geneation Pat2 NSK continually challenges the status quo to exploe new possibilities. As ou design philosophy does not allow us to compomise quality in manufactuing, we ae diven to develop total solution technologies. By using the latest mateial and analysis technologies we ae able to design and manufactue exceptional, high pefomance pecision beaings. NSK will always stive to achieve the quality and pefomance that will be equied in next geneation beaings. Contents Pat2. Featues of Pecision Beaings Metallugical Technologies to Extend Beaing Life P14 Ceamic Rolling Elements P16 Cages P18 Beaing Components P20 Poduct Range P22 Pefomance of Each Beaing Type P

9 Metallugical Technologies to Extend Beaing Life Pat 1 Pat2 Pat 3 Pat 4 Pat 5 Pat 6 Pat 7 Pat 8 Thee types of steel mateials suppot the long life and high pefomance of NSK supe-pecision beaings NSK has established goundbeaking evaluation techniques fo inclusions in steel and steel-making pocedues. These technologies make it possible to develop mateials fo long-life, high-pefomance olling beaings. Thee types of steel mateials SHX steel that withstands ulta high-speed otation envionments, EP steel that exhibits high eliability unde heavy load envionments, and Z steel that achieves extended opeation life unde geneal conditions suppot NSK supe-pecision beaings. Z Steel as a Standad Mateial fo Supe-Pecision Beaings Z Steel Life, L 10 Cycle Standad Long Life Mateial 1.8 Times Longe Fatigue Life than Conventional Vacuum Degassed Steel It is well known that the olling fatigue life of high cabon chome beaing steel (SAE52100, SUJ2) used fo olling beaings is significantly affected by non-metallic inclusions. Life tests show that oxide non-metallic inclusions exet a paticulaly advese affect on olling fatigue life. Z Steel, with lowe oxide non-metallic inclusions, exhibits impoved pefomance. Featues of Z Steel Z Steel is poduced by educing non-metallic inclusions, oxides and othe inclusions such as Ti, o S, inside the steel. Beaings made of this steel delive significantly extended sevice life, up to 1.8 times longe, compaed to conventional vacuum degassed steel. Oxygen Content in Steel and Opeating Life Z Steel Vacuum degassed steel fo the beaings in a wide vaiety of industies Oxygen Content in Steel, ppm EP Steel fo Highe Reliability unde Heavy Load Envionments EP Steel Numbe of Paticles Exta Long Life and High Reliability 3 Times Longe Fatigue Life than SUJ2 Steel Development of innovative techniques fo evaluating oxide nonmetallic inclusions and the establishment of steel-making pocedues esulted in EP steel that achieved a damatic advance in beaing eliability. Featues of EP Steel Beaings made fom EP Steel exhibit inceased eliability due to minimal vaiation in life esulting fom the new evaluation technique and significantly educed impuities. The establishment of a new evaluation technique NSK established the NSK-ISD2 Method, an image analysis system and a special steel-making pocedue, to impove the evaluation of oxide non-metallic inclusions. Impovement of steel-making pocedues The intoduction of this technique into steel manufactuing technology significantly impoved puity and educed nonmetallic inclusions compaed to Z Steel. EP Steel contains fewe lage paticles than eithe Vacuum Ac Remelted (VAR) o conventionally efined Z Steel. Puity compaison though image analysis EP Steel Oxide Paticle Size, µm SUJ2 EP 3 µm 40C. >5 µm 5C. >10 µm 0C. [O] : (5.5)ppm View Numbe of Paticles Cumulative failue pobability, % Z Steel Oxide Paticle Size, µm Test conditions (Beaing: 6206) P/C: 0.71 Speed: min 1 Lubication: Foced ciculation lubication SUJ2 Z 3 µm 404C. >5 µm 100C. >10 µm 8C. [O] : (8)ppm View Fatigue Life Subsuface oiginated flaking test EP Steel Z Steel SHX Steel Endues Ulta Speed Rotation Envionments SHX Steel Wea Resistance Amount of wea, g Time until seizue, sec Cumulative failue pobability, % Wea esistance of each mateial (2 cylindical olles wea test) SHX SUJ2 M50 Seizue Resistance Fatigue Life SHX SUJ Sliding distance, m Dy seizue limit test (4 balls test) SHX Mateial Clean lubication Test conditions 10 (Beaing: 6206) 5 P/C: 0.71 Tempeatue: 160 C Speed: min 1 Oil film paamete ( ): Life, h M50 Subsuface oiginated flaking test Poducts made of Z Steel Poducts made of EP steel Poducts made of SHX Steel Heat Resistant Steel Extends the Life of Beaings Used in Ulta High-Speed Applications 4 Times Longe Fatigue Life than SUJ2 Steel, at 20% Highe Speed SHX is a heat-esistant steel esulting fom NSK s special heat teatment technology. Featues of SHX Steel SHX steel exhibits simila heat esistant pefomance to M50 steel, which is used fo beaings on the main shaft of jet engine applications whee tempeatues each 300 C, and featues lowe fiction pefomance, while at the same time exceeding M50 steel in wea and seizue esistance and fatigue life. This level of heat esistance, lowe fiction pefomance and indentation esistance epesent ideally suited steel chaacteistics fo ulta high-speed machine tool beaings. Patent Numbe: JP PV value, kgf/mm 2 m/s Cumulative failue pobability, % Load cylindical olles wea test Lubicant 7 min 1 10 min 1 SUJ2 SHX SUJ2 M50 Test conditions Suface pessue : 880 MPa Sliding atio : 30% Lubication : Spindle oil (2 cc/min) Tempeatue : Room tempeatue Oil bath seizue limit test (4 balls test) M50 Mateial Contaminated lubication Test conditions (Beaing: 6206) P/C: Tempeatue: 140 C Speed: min 5 1 Foeign debis Hadness: Hv540 Size: µm Life, h SHX Suface oiginated flaking test 4 balls test Load Rotating Fixed NSK uses Z Steel as a standad mateial Ball Scew Suppot Beaings Ulta High-Speed ROBUST Seies fo Ulta High-Speed Machine Tool Main Spindles 14 15

10 Ceamic Rolling Elements Pat 1 Pat2 Pat 3 Pat 4 Pat 5 Pat 6 Pat 7 Pat 8 Less heat is geneated, making possible ulta high-speed otation. Ceamic hybid beaings have many excellent pefomance chaacteistics such as heat esistance, extended life, light weight, lowe themal expansion, electically non-conductive, and thus can be used in an infinite numbe of applications as a new geneation mateial. Ealy on NSK s knowledge of mateials and beaing manufactuing led us to utilize one ceamic in paticula, silicon nitide (Si 3 N 4 ), fo the olling elements in ceamic hybid beaings. Hybid beaings with ceamic elements have eaned a good eputation in the field fo ulta high speed combined with ulta high accuacy, a pefomance combination that is not achievable in beaings with steel olling elements. Seizue Resistance Relative to steel balls, ceamic balls have a highe seizue esistance. Oute ing tempeatue ise, C 0 Steel balls Seizue Ceamic balls Oil Inteuption Test Result, s Resupply 30 Cutting by NSK Spindle using Ceamic Ball Beaing End Mill: 16 Wok Mateial: A5052 Rotational speed: min cm 3 /min High speed and low-heat geneation Light weight As the density is 40% lowe than that of steel, the centifugal foce applied to the olling elements is smalle, thus extending beaing life. Low coefficient of linea expansion In applications involving high speed opeation, although the tempeatue of the beaing is high, this low coefficient esults in lowe peload and lowe heat geneation. Low fiction The slip of the olling element duing opeation is educed, and this means less heat is geneated. Calculated esult of heat geneation Less heat is geneated, making possible ulta highspeed otation. High Rigidity Ceamic balls have a Young s Modulus that is 50% highe than that of steel, making it an ideal mateial fo use in machine tool spindles equiing igid cutting pefomance. Cutting by NSK Spindle using Ceamic Ball Beaing Axial displacement, µm BNR10S (Steel balls) 65BNR10H (Ceamic balls) 65BAR10H (Ceamic balls) 65BAR10S (Steel balls) Axial load, N 65BTR10S (Steel balls) 65BTR10H (Ceamic balls) Face Mill: 80 Wok Mateial: S50C Rotational speed: min cm 3 /min Dynamic fictional loss, w Spin Slip Gyoscopic Slip Rolling fiction between balls and aceways Othes Dynamic fictional loss, w Rolling fiction between balls and aceways Spin Slip Othes Gyoscopic Slip High Accuacy NSK s expetise in the manufactuing of balls and olles ove the yeas along with impovements in the sinteing pocess and the gade of mateials used enables NSK to poduce ceamic balls and cylindical olles that featue a highe level of accuacy 98 than steel mateials. Beaings using these high-accuacy ceamic olling elements suppot high-accuacy machining Speed, min Speed, min The Oute Ring Tempeatue Rise in High Speed Opeation Oute ing tempeatue ise, C Steel balls Ceamic balls NSK Spindle that achieved 4 million d m n using ceamic ball beaings Size: 9/32'' Magnification: times Roundness of ceamics ball Ceamic ball beaing 278 Roundness of mateial being gound 0.14 µm 1 µm/div High magnification ( times) Spheicity measuing equipment Speed, min 1 Ceamic olle beaing Ceamic ball beaing

11 Cages Pat 1 Pat2 Pat 3 Pat 4 Pat 5 Pat 6 Pat 7 Pat 8 Engineeed polyme cages with highe speed capability and lowe fiction Because of light weight (polyme density is 1/6 that of bass), easy fomability, and high coosion esistance, polyme mateials ae used widely in beaing cages. Polymes can be engineeed to have lowe fiction and thus lowe heat geneation and highe speed capability. Polymes can be engineeed fo low wea, thus extending gease life. The engineeed polyme cage is well suited fo beaings used in machine tool main spindles. Cage fo Angula Contact Ball Beaings Ball Guided Polyamide Cage (TYN) Low Noise Oute Ring Guided Phenolic Cage Rolle Guided Machine Bass Cage Rolle Guided PPS Cage Oute Ring Guided PEEK Cage Ball Guided Polyamide Cage This special design allows the beaing to have lowe fiction and lowe noise. This cage is effective with gease lubication. The intenal fee space of the beaing in this cage is lage than that with oute ing guided cage so, it is possible to keep moe gease inside of the beaing. The peiod of the gease unning-in pocedue fo a beaing with this cage is shote than that of a beaing, with a phenolic cage. Cage fo Double-Row Cylindical Rolle Beaings Rolle Guided PPS Cage (TB) Engineeed Polyme High Rigidity Optimal olle-guided cage design with consideation fo stength and fiction. Excellent physical popeties include highe stength, toughness, wea and fatigue esistance compaed to cuent polyamide cage mateial. High tempeatue esistance up to a maximum of 220 C. Ulta High-Speed Angula Contact Ball Beaings ROBUST Seies Cage Pefomance Test Result Oute ing tempeatue ise, C T cage TYN cage Beaing: 65BNR10H-DB Peload afte mounted: Position peload 300N Lubication: Gease The tempeatue ise of the beaing with a TYN cage is lowe than that with a Phenolic cage at a otational speed lowe than 1.4 million dmn Cage fo Single-Row Cylindical Rolle Beaings Oute Ring Guided PEEK Cage (TP) Engineeed Polyme Double ow CRB High Rigidity Seies Ulta High-Speed 0 Speed min d mn Minimizing cage defomation to pemit stable high-speed otation. High tempeatue esistance up to a maximum of 240 C. Excellent wea-esistant pefomance and suited to minimal oil lubication. Physical popeties include high stength, toughness, wea and fatigue esistance. Oute Ring Guided Phenolic Cage (T, TR) Ulta High-Speed The otational movement of the oute ing guided cage is moe stable in high-speed opeation. Standad Seies Angula Contact Ball Beaings Standad Seies Ulta High-Speed Angula Contact Ball Beaings ROBUST Seies Rolle Guided Machined Bass Cage (MB, MR) This cage demonstates high tempeatue esistance, high stength, and high igidity. Ulta High-Speed Single Row CRB Robust Seies Geneal Pupose 18 19

12 Beaing Components Pat 1 Pat2 Pat 3 Pat 4 Pat 5 Pat 6 Pat 7 Pat 8 NSK supe-pecision beaings with optimal mateials and intenal design Angula Contact Ball Beaings (Standad Seies) Cylindical Rolle Beaings Cages Rolling elements Ceamics SUJ2 Cage Polyamide Phenolic Rolling elements SUJ2 Rings SUJ2 NN30 PPS Bass Type Rings Rolling elements Cages Rings SUJ2 Standad SUJ2 SUJ2 PPS(TB)/ Bass (MB) Cage Angula Contact Ball Beaings (ROBUST Seies) Type Rings Rolling elements Cage SUJ2 type SUJ2 SUJ2 Polyamide 46 (TYN) Ceamic ball type SUJ2 Ceamics Phenolic (TR) Rolling elements Ceamics SHX SUJ2 Rings SHX SUJ2 N10 PEEK Bass Type Rings Rolling elements Cage Standad RS SUJ2 SUJ2 SUJ2 SUJ2 Bass (MR) RX SHX SHX PEEK(TP) RXH SHX Ceamics Rolling elements Ceamics SUJ2 Cage Polyamide Phenolic PEEK Angula Contact Thust Ball Beaings fo Ball Scew Suppot Rings SHX SUJ2 Rolling elements SUJ2 Cage Polyamide Bass Type Rings Rolling elements Cage S H X SUJ2 SUJ2 SHX SUJ2 Ceamics Ceamics Polyamide 46 (TYN) Phenolic (T) PEEK (T42) Rings SUJ2EP SUJ2 Type Rings Rolling elements Cage Fo machine tool applications Fo injection molding applications SUJ2EP SUJ2 SUJ2 SUJ2 Polyamide 66 Polyamide 46/ Bass 20 21

13 Supe Pecision Beaings Poduct Range Seveal types of supe pecision beaings ae available fom NSK, including the ROBUST seies of high pefomance beaings, the special seies of beaings fo unique and specialized applications, and the standad seies beaings. High Pecision Angula Contact Ball Beaings Standad Seies Basic NSK supe pecision beaings manufactued to confom to ISO standad. Standad Seies 70xx, 72xx, 79xx seies Thee types of contact angle: 15 (C), 25 (A5), 30 (A) Two types of cage design: Select eithe phenolic (TR) o polyamide (TYN), depending on application equiements Pat 1 Pat2 Pat 3 Pat 4 Pat 5 Pat 6 Pat 7 Pat 8 Ulta High-Speed Single Row Cylindical Rolle Beaings ROBUST seies is the high pefomance seies of NSK supe pecision beaings. ROBUST Seies ROBUST Seies Standad Seies High pefomance cylindical beaings designed fo ulta high-speed applications, such as machining cente spindles. Two types of cage mateial: Bass (MR) (1) and PEEK esin (TP) Thee types of olle mateial: Steel, SHX and Ceamic Ulta high-speed ROBUST RXH design can be used up to 2.2 million d m n (1) MR cage is used in the standad seies Standad Seies Ulta High-Speed Angula Contact Ball Beaings ROBUST Seies Double Row Cylindical Rolle Beaings Standad Seies ROBUST Seies (BNR, BER) High pefomance beaings developed fo high-speed opeation with low tempeatue ise. Suitable fo ulta high pecision machining applications, and ulta high-speed applications. Two types of contact angle: 18 (BNR), 25 (BER) Two types of ball mateial: steel (S type) and Ceamic (H and X type) Two types of cage design: Select eithe phenolic (T) o polyamide (TYN), depending on application equiements ROBUST seies also can be used fo ulta high-speed applications of ove 3 million d m n High Rigidity Seies Designed to delive high igidity in high-speed applications such as lathe spindles. Two types of cage mateial: Bass (MB), PPS esin (TB) Standad specification E44: Oute ing oil holes and goove Sealed Angula Contact Ball Beaings Special Seies Angula Contact Thust Ball Beaings fo Ball Scew Suppot Special Seies Special Seies Pegeased and sealed to educe handling poblems. Suitable fo maintenance of machine tool spindles. Standad seies supe pecision angula contact ball beaings ROBUST seies high-speed angula contact ball beaings Boe size ange: mm in ISO seies 10 and 19 (70xx and 79xx) fo Machine Tool Applications High igidity thust beaings designed specifically fo ball scew suppot applications in machine tools. Contact angle: 60 Can be univesally matched to any equied igidity specification o life cycle A pegeased line using special gease is also available A new seies is available, supplied with contact seals and watepoof gease High-Speed Angula Contact Thust Ball Beaings ROBUST Seies Angula Contact Thust Ball Beaings fo Ball Scew Suppot Special Seies ROBUST Seies (BAR, BTR) High igidity thust beaings fo lathe applications. Two types of contact angle: 30 (BAR), 40 (BTR) Two types of ball mateial: steel (S type) and Ceamic (H type) fo Injection Molding Machines The high load capacity design delives five times the life expectancy compaed to ball scew suppot beaings fo machine tool applications of a simila size. The numbe of ows can also be educed. Easie handling than tapeed olle beaings o thust spheical olle beaings as a esult of non sepaable configuation Optimum ball beaing design esults in lowe otational toque Can be univesally matched to any equied igidity specification o life cycle Ulta High Pecision Angula Contact Ball Beaings ROBUST Seies High Pecision Deep-Goove Ball Beaings Special Seies ROBUST Seies (BGR) High Pefomance beaings developed specifically fo intenal ginding o high-speed moto applications unde sping peload. Boe size ange: 6 25 mm, contact angle: 15 Two types of ball mateial: steel (S type) and Ceamic (H and X type) Non sepaable type Univesal combinations (DU and SU) Special Seies Suitable fo high-speed and high pecision motos. Two types of cage: Ball guided polyamide cage (T1X,TYA) Fo quiet opeation, with low vibation 22 23

14 ROBUST Seies Ulta High-Speed Angula Contact Ball Beaings Pat 1 Pat2 Pat 3 Pat 4 Pat 5 Pat 6 Pat 7 Pat 8 Designed to achieve high-speed opeation combined with low heat geneation ROBUST Seies High pefomance Benefits Low Heat Geneation High Seizue Resistance Bette Tempeatue Stability Robustness Stable duing High-Speed Opeation Featues of XE seies High-Speed Pefomance (in Position Peload) High-speed pefomance in position peload to a maximum of 2.5 million d m n with jacket cooling (Max. 2.7 million d m n without jacket cooling). Silent Opeation Silent opeation 3-5 db quiete than conventional oil-ai lubication. Oientation Remains stable in eithe vetical o hoizontal spindle oientation. Reduced Ai Consumption Ai consumption can be 1/3 elative to conventional oil-ai lubication. XE Type Suitable fo silent opeation due to educed ai-noise achieved though oil-ai lubication design Mateial of Inne/Oute Rings: Heat Resistant Steel SHX Ceamic Balls Cage selection based on speed equiements Oute Ring Guided Phenolic Cage: up to 2.5 million d mn Oute Ring Guided PEEK Cage: ove 2.5 million d mn ROBUST Seies X Type High pefomance beaings demonstating high wea and seizue esistance duing ulta high-speed opeation Analysis Data Sophisticated analysis softwae takes into account the slip inside the beaing and simulates tempeatue ise to establish optimum design specifications. By educing the heat geneated, ROBUST seies beaings emain much moe stable duing high-speed opeation than cuent seies beaings. Heat geneation, W Heat Geneation with Gease Lubication Analytical Value ( 65 mm) Standad beaings ROBUST Seies Speed (min ) Tempeatue ise of oute ing, C Oute Ring Tempeatue Rise with Gease Lubication Test Result ( 65 mm) Standad beaings ROBUST Seies Speed (min ) Mateial of Inne/Oute Rings: Heat Resistant Steel SHX Ceamic Balls Oute Ring Guided Phenolic Cage Test Data ROBUST Seies H Type High pefomance beaings that combine high-speed opeation with low heat geneation Mateial of Inne/Oute Rings: Steel Ceamic Balls Cage selection based on speed equiements Ball Guided Polyamide Cage: up to 1.4 million d mn Oute Ring Guided Phenolic Cage: ove 1.4 million d mn Oute ing tempeatue ise, C Tempeatue Data with Gease Lubication X type H type S type Beaing: 65BNR10-DBB Peload afte mounted: 300 N Lubication: MTE Gease Speed min d mn Oute ing tempeatue ise, C Tempeatue Data of With cooled housing Without cooled housing Beaing: 65BNR10XETDB Peload afte mounted: 200 N Lubication: VG32, 0.03 cc/8 min, 2 nozzles Speed min d mn ROBUST Seies S Type Steel ball beaings fo optimal cost Mateial of Inne/Oute Rings: Steel Steel Balls Ball Guided Polyamide Cage High speed Oute ing tempeatue ise, C Tempeatue Data with Oil-Ai Lubication X type H type Beaing: 70BNR10-TDB Peload afte mounted: 150 N Lubication: VG22, 0.03 cc/8 min, 2 nozzles With cooled housing Speed min d mn Noise, db XE type X type Noise Compaison Speed min d mn 24 25

15 ROBUST Seies Standad Seies High Pefomance Cylindical Rolle Beaings Pat 1 Pat2 Pat 3 Pat 4 Pat 5 Pat 6 Pat 7 Pat 8 Designed to achieve high speed pe fomance combined with high igidity 1 Low Heat Geneation Featues of High Rigidity Double Row Cylindical Rolle Beaings Longe Beaing Life Benefits 2 Impoved Seizue Resistance The PPS (engineeed polyme) cage is heat esistant and povides high igidity. As compaed to a bass cage, this cage eliminates any wea paticles, allowing an extended gease life. 3 Stable Opeation in Ulta High Speed Limiting Speed Tempeatue Rise with Gease Lubication High pefomance Ulta High-Speed Single Row Cylindical Rolle Beaings ROBUST Seies RXH Type Highest pefomance fo optimum seizue esistance duing ulta high-speed opeation Mateial of Inne/Oute Rings: Heat Resistant Steel SHX Ceamic Rolles Oute Ring Guided PEEK Cage Limiting Speed, min Rings & olles: Steel Gease Lubication 0.85 million Boe, mm Oute ing tempeatue ise, C Beaing with new plastic cage (PPS) Beaing with cuent plastic cage (Polyamide) Beaing: NN3019 Lubication: gease Cleaance afte mounted: 0 µm 0 Speed min d mn Double Row Cylindical Rolle Beaings High Rigidity Seies High pefomance seies with a newly developed polyme cage Mateial of Inne/Oute Rings: Steel Rolle Guided PPS Cage o Rolle Guided Bass Cage (Selection based on application equiements) Ulta High-Speed Single Row Cylindical Rolle Beaings ROBUST Seies RX Type High pefomance with wea and seizue esistance duing ulta high speed opeation Mateial of Inne/Oute Rings: Heat Resistant Steel SHX SHX Rolles Oute Ring Guided PEEK Cage Featues of the ROBUST seies Ulta High-Speed Single Row Cylindical Rolle Beaings Low Heat Geneation Intenal design and advanced cage mateial esult in low heat geneation. Seizue Resistance RX and RXH types ae made with SHX steel esulting in impoved seizue esistance. High Speed Capability RS, RX and RXH types have cages made of heat esistant PEEK mateial fo ulta high speed opeation (ove 2.0 million d m n). Single Row Cylindical Rolle Beaings Standad Seies Standad type beaing with bass cage Mateial of Inne/Oute Rings: Steel Rolle Guided Bass Cage Ulta High-Speed Single Row Cylindical Rolle Beaings ROBUST Seies RS Type Designed to delive cost effective high-speed pefomance Mateial of Inne/Oute Rings: Steel Steel Rolles Oute Ring Guided PEEK Cage High speed Limiting speed, min RS type: 1.4 million Limiting Speed RXH type: 2.2 million Oil-ai lubication Boe, mm Oute ing tempeatue ise, C Tempeatue Rise with Oil-Ai Lubication Test conditions Beaing: N1014RXHTP Lubication: oil-ai (VG22) Cleaance afte mounted: 0 µm Speed min d mn 26 27

16 ROBUST Seies High-Speed Angula Contact Thust Ball Beaings ROBUST Seies Ulta High Pecision Angula Contact Ball Beaings High pefomance beaings that combine high-speed capability with high igidity ROBUST Seies Ulta high-speed intenal ginding spindle beaings fo high accuacy and longe life ROBUST Seies (BGR) 1 High-Speed Capability 1 Optimum Intenal Design Benefits 2 Low Heat Geneation Benefits 2 Easy Handling Due to Non Sepaable Featue 3 High Accuacy 3 Fee Choice of Aangement with Univesal Combination High-Speed Angula Contact Thust Ball Beaings BTR10 Seies 40 contact angle and high axial igidity and low heat geneation. Intechangeable with TAC seies. High-Speed Angula Contact Thust Ball Beaings BAR10 Seies 30 contact angle delives highe speed capability. Intechangeable with BTR and TAC seies. Double Row Angula Contact Thust Ball Beaings TAC Seies 60 contact angle with the highest axial igidity. Featues of Angula Contact Thust Ball Beaings Featues of the BGR Seies High Accuacy Due to the high degee of accuacy, they ae paticulaly suited fo lathe spindle applications. Themocouple 100BAR10STYN 100BTR10STYN Themocouple Optimum Design Optimum oute ing guided cage design fo bette lubication. Inne ing shoulde elieved to enable a stable supply of oil into the beaing. Intechangeable To adjust spindle stiffness chaacteistics, BTR and BAR seies can be intechanged with TAC seies, with minimal modification of the spindle. (See figue on the ight). Data with Gease Lubication 100TAC20X NN3020KR Test machine stuctue NN3017KR Axial Load and Axial Displacement Longe Life Heat esistant SHX steel fo longe life. Easy Handling Non sepaable stuctue makes handling easy. Ulta High Accuacy ISO class 2 (ABMA ABEC9) is the standad. Oute ing tempeatue ise, C TAC20X (α 0=60 ) 100BTR10STYNDB (α0=40 ) 100BAR10STYNDB (α0=30 ) Gease lubication (Isoflex NBU15) Speed min d m n Axial displacement, m µ BAR10STYNDB (α 0=30 ) 100BTR10STYNDB (α0=40 ) 100TAC20X (α 0=60 ) Axial load, N Univesal Combination Beaings can be configued in the usual aangements of DB/DF/DT, as well as a vaiety of othe aangements. Oil supply

17 Special Seies Ball Scew Suppot Angula Contact Thust Ball Beaings Special Seies Ball Scew Suppot Angula Contact Thust Ball Beaings (fo Machine Tool Applications) (fo Injection Molding Machines) High pefomance special beaings with high igidity TAC B Seies These special high pefomance beaings can simplify machine design and educe costs TAC 02, 03 Seies 1 Longe Life 1 Space Saving, High Load Capacity Benefits 2 3 Lowe Toque Easy Handling Benefits 2 3 High Reliability Easy Handling 4 High Accuacy 4 Reduced Toque fom Optimized Design Featues of Ball Scew Suppot Beaings fo Machine Tools Longe Life Components made fom longe life EP extemely puified steel. High Rigidity Special intenal design (60 contact angle and moe balls) fo highe axial igidity. Lowe Toque Lowe stating toque than eithe tapeed o cylindical olle beaings means high otation accuacy even at low diven powe. Univesal Combination Beaings can be configued in the usual aangements of DB/DF/DT, as well as a vaiety of othe aangements. A pegeased option is also available (with Alvania No.2 gease). Easy Handling and Inceased Reliability New seies with contact seals and watepoof gease has highe eliability and easie handling. Single univesal combination (SU) is the standad fo this seies. High Running Accuacy New polyamide cage fo high unning accuacy. Featues of Ball Scew Suppot Beaings fo Injection Molding Machines High Reliability High load capacity design delives five times the life value compaed to the similaly sized TAC B seies. Easy Handling Easie to handle and use than tapeed olle beaings o thust spheical olle beaings due to the non sepaable design. Simplified Design Leads to Reduced Costs Peload is peset so assembly is fast and without any peload adjustment. Design of special pats fo peload adjustment is unnecessay, which saves time and cost. Lowe Rotational Toque Optimal intenal design fo lowe toque (i.e., in cases whee olle beaings ae cuently being used because of lage load, these beaings can be used to educe the beaing toque geneated by olle beaings). Coss Section of the Beaing fo Machine Tools and Injection Molding Machines Coss Section of TAC B With Seal Coss Section of TAC B Coss Section of TAC03AT

18 Special Seies Sealed Angula Contact Ball Beaings Othe Poducts High Pefomance Geases fo Machine Tool Spindles Suitable fo spindle maintenance ROBUST Seies and Standad Seies MTS, MTE, ENS Featues of Sealed Angula Contact Ball Beaings Featues of Geases fo Machine Tool Spindles Easy Handling No need to gease the beaing duing spindle assembly. Envionmentally Fiendly Sealed design avoids gease loss. MTS MTE ENS Contains uea thickene and delives highe heat esistance. Recommended fo use with ulta high speed machine tool spindles Fomulated to handle highe load capacities. Recommended fo use in high speed machine tool spindles. Envionmentally fiendly thanks to biodegadability. ROBUST Seies with T cage ROBUST Seies with TYN cage Standad Seies with TR cage Othe Poducts Sealed Pecision Spaces MTE and MTS ae available in 100 g tubes as well as 1 kg cans. Sealed spaces eliminate the possibility of contamination Pecision spaces available fo machine tool spindles Chaacteistics of each gease Items Condition MTS MTE ENS Test Method Featues of Sealed Pecision Spaces Envionmentally Fiendly Sealed design pevents gease loss. High Reliability Reduced contamination fom dust o coolant in gease lubicated spindles. Labyinth stuctue Sealed space Thickene Uea Baium Complex Uea Base Oil Kinematic Viscosity of Base Oil (mm 2 /S) Este+Synthetic hydo cabon oil Este Oil Polyol Este Oil 40 C JIS K2283 Woked Penetation 25 C, 60 W JIS K2220 (Clause7) Dopping Point ( C) > 220 > 200 > 260 Evapoation (mass%) 99 C 22 H Oil Sepaation (mass%) 100 C 24 H JIS K2220 (Clause8) JIS K2220 (Clause10) JIS K2220 (Clause11) Oil outlet 32 33

19 Selecting the Right Beaing is Citical Pecision beaings ae designed to delive the high accuacy, high otational speed, and high igidity needed fo demanding machine tool applications. As each application has its own unique equiements, and each type of beaing has diffeent chaacteistics, it is essential to select the type of beaing based on the specific demands of a given application. Take Advantage of NSK Technical Suppot when Selecting Beaings NSK is committed to helping customes select the pope beaings that will delive the best pefomance based on the application involved. When designing a new spindle, including ulta high speed, specialized o custom applications, o making you beaing selection, please don t hesitate to ask us fo technical assistance. We have the expeience and expetise in state-of-theat, high speed, main shaft spindle technology to assue that you get the vey best beaings fo you application. Fo moe infomation on the latest NSK technology, please visit ou Web site o call today. Contents Pat3 Pat3. Beaing Selection P36 Typical High-Speed Main Shaft Spindle Stuctues P38 Othe Spindle Stuctues P40 Featues of Angula Contact Ball Beaings P42 Featues of Cylindical Rolle Beaings P44 NSK Web Site

20 BEARING SELECTION Pat 1 Pat 2 Pat3 Pat 4 Pat 5 Pat 6 Pat 7 Pat 8 The chat below outlines the coect five step pocedue to follow when selecting the pope beaing fo a typical high-speed spindle application, including the factos to be consideed in each stage of the selection pocess. Remembe, NSK technical suppot is always at you disposal when designing a new spindle, an ulta high-speed spindle o a spindle fo a unique specialized application. We offe customes ou expeience and ou expetise in advanced technology. When designing a new main shaft spindle, we ecommend a thoough analysis of the desied 1 Main Shaft Spindle Concept Speed Rigidity Spindle Heat Geneation Running Accuacy Life Reliability spindle pefomance befoe selecting the beaing. In designing the spindle, it is necessay to detemine which pefomance facto is most impotant. Fo example, deciding if the otational speed is moe impotant than the igidity, o vice vesa. Once the pefomance factos ae pioitized poceed to the next step. Afte the pefomance analysis of the main shaft has been completed, the next step is to detemine the stuctue of Beaing Type Dive Type the main shaft. To detemine the optimum stuctue, consideation must be given to each individual component: the 2 Main Shaft Stuctue Beaing Aangement Lubication beaing design (ball beaing o olle beaing); combination (the numbe of ows); type of dive (belt, gea, coupling o integal moto); and lubication system (gease, oil-ai, oil mist, o jet). Cae must be taken to ensue that the stuctue Pat 3 Peload Method Jacket Cooling is compatible with the citeia and pioity established in you analysis of spindle pefomance. Please efe to the chat on Pages 38 39, which shows the elationship between the main shaft stuctue and its igidity and speed. 3 Main Shaft Size Shaft Diamete and Length Distance between Beaings Limiting Speed Main Shaft Rigidity Natual Fequency of the Shaft Beaing Seies Afte the stuctue has been detemined, the dimensions of the shaft must be detemined, including diamete, length, and distance between the beaings. The size of the main shaft will detemine the limiting speed of the beaing, the igidity of the main shaft, and the natual fequency of the main shaft. As the size, type, combination of beaing used, and the method of lubication all affect the limiting speed, please efe to Pat 4 and Pat 5 befoe making a final Pat 4 Pat 5 detemination. Once the size and type of the beaing ae selected, the specification of the beaing should be Fatigue Life Peload detemined. In ode to select the appopiate cleaance, o peload, of the beaing it is necessay 4 Beaing Pefomance Rigidity Beaing Heat Geneation Lubication Life Cleaance Running Accuacy Static Load Capacity to conside such factos as fatigue life, axial and adial igidity, and heat geneation. Cleaance o peload must be selected caefully, as these factos have the lagest impact on oveall spindle pefomance, especially duing high speed opeation. If the peload is wong it may cause poblems such as ealy failue o seizue. Sometimes it is necessay to epeat step 3, o even steps 2 and 3, befoe the most accuate spindle design is achieved. Pat 5 Afte the specification of the main shaft is complete, the final stage is the specification of the Shaft Run out Nut Tightening Foce assembly method. Accuacy of the shaft and housing at the beaing seats is impotant. Specify 5 Main Shaft Assembly Housing Accuacy Fit and Cleaance Checking Peload Checking Cleaance the fit and cleaance of the beaings to the shaft and housing. Use the coect nut tightening foce to fix the beaings. And double check that the peload, o cleaance, afte the beaing has been mounted is coect. Pat 6 Compession Amount of Retaining Cove Quantity of Oil Supply 36 37

21 TYPICAL HIGH-SPEED MAIN SHAFT SPINDLE STRUCTURES (Speeds Highe than 0.7 million d m n) Pat 1 Pat 2 Pat3 Pat 4 Pat 5 Pat 6 Pat 7 Pat 8 1 Beaing Aangement 1 Oil-ai lubication Gease lubication d m n 3.5M d m n 2.0M Font side: Ulta high-speed angula contact ball beaing duplex sets (DT) Rea side: Ulta high-speed angula contact ball beaing duplex sets (DT) Spindles with this aangement ae suited fo ulta high speed opeation and use constant pessue peload. Although this spindle has lowe igidity it delives highe speed capability with a lowe tempeatue ise pefomance elative to a spindle with position peload. Applications: Machining Cente, Ginding Machine, High Fequency Spindle, etc. 2 Beaing Aangement 2 Rotational Speed (dmn) Oil-ai lubication Gease lubication d m n 2.5M d m n 1.5M Beaing Aangement 3 Font side: Ulta high-speed angula contact ball beaing quad sets (DBB) Rea side: Ulta high-speed single ow cylindical olle beaing (In case of angula contact ball beaings, eithe position o constant pessue peload is applicable) Spindles with this aangement will have lowe speed capability, and highe adial and axial igidity elative to Beaing Aangement2. Applications: NC Lathe, NC Milling Machine, Machining Cente, etc. Font side: Ulta high-speed angula contact ball beaing duplex sets (DB) Rea side: Ulta high-speed single ow cylindical olle beaing (In case of angula contact ball beaings, eithe position o constant pessue peload is applicable) Spindles with this aangement ae suited fo ulta high-speed opeation and use position peload. They achieve highe adial and axial igidity than spindles with Beaing Aangement1. It is possible to use a cylindical olle beaing on the ea side, fo bette slide pefomance. Applications: Machining Cente, Ginding Machine, High Fequency Spindle, etc. 3 4 Oil-ai lubication Gease lubication d m n 2.2M d m n 1.3M Oil-ai lubication Gease lubication d m n 2.2M d m n 1.3M Beaing Aangement 4 Font side: Ulta high-speed single ow cylindical olle beaing, angula contact ball beaing duplex sets (DB) Rea side: Ulta high-speed single ow cylindical olle beaing (In case of angula contact ball beaing, eithe position o constant pessue peload is applicable) Spindles with this aangement have high-speed capability simila to spindles with Beaing Aangement 3. As thee is a cylindical olle beaing in the font side, the adial igidity is high, so it is possible to have both high speed and heavy cuts. Applications: NC Lathe, NC Milling Machine, Machining Cente, etc. Beaing Aangement Beaing Aangement 6 Oil-ai lubication Gease lubication d m n 1.0M d m n 0.8M Font side: Ulta high-speed angula contact ball beaing tiplex sets (DBD) Rea side: Ulta high-speed single ow cylindical olle beaing (In case of angula contact ball beaing, eithe position o constant pessue peload is applicable ) Spindles with this aangement will have lowe speed capability, and highe adial and axial igidity elative to Beaing Aangement 2, and lowe speed capability and igidity elative to Beaing Aangements3and 4. Applications: NC Lathe, NC Milling Machine, Machining Cente, etc. Oil-ai lubication Gease lubication d m n 1.8M d m n 1.2M Rigidity of the Main Shaft Font side: High igidity double ow cylindical olle beaing, angula contact ball beaing duplex sets (DB) Rea side: High igidity double ow cylindical olle beaing Although spindles with this aangement have lowe speed capability, the adial and axial igidity of these spindles ae highest. Applications: NC Lathe, NC Milling Machine, Machining Cente, etc

22 OTHER SPINDLE STRUCTURES Pat 1 Pat 2 Pat3 Pat 4 Pat 5 Pat 6 Pat 7 Pat 8 Boing Head High Pecision Spindle fo Lathe Ginding Spindle Live Cente High Fequency Spindle Wok Head Spindle 40 41

23 FEATURES OF ANGULAR CONTACT BALL BEARINGS Pat 1 Pat 2 Pat3 Pat 4 Pat 5 Pat 6 Pat 7 Pat 8 The main featues of the Angula Contact Ball Beaing (ACBB) A pedefined contact angle They ae used in matched combinations with peload In selecting Angula Contact Ball Beaings, it is impotant to conside the above two featues, as each angula contol ball beaing has specific featues and pefomance. Be sue to caefully conside the effects of changes in contact angle and peload on pefomance so that you select the ACBB that is best suited to the application. The following gaphs summaize the elative pefomance of each type of ACBB (by seies and dimensional seies), depending on the contact angle, peload, and combination. The Effect of Contact Angle As the contact angle inceases, Angula Contact Ball Beaings have a highe axial load capacity, but a lowe speed capability. Thus, the ACBB with a smalle contact angle is bette suited fo high speed and high adial load applications. The figue below compaes the igidity, limiting speed and tempeatue ise of a 7020 Angula Contact Ball Beaing with diffeent contact angles: C angle (15 ), A5 angle (25 ) and A angle (30 ). Unde the same light peload level (L), the beaing with C angle has highe adial igidity with lowe tempeatue ise elative to the beaing with A angle. The beaing with A angle has the highest axial igidity, thee times highe than that of the beaing with C angle, but the limiting speed is lowe than the othes. Pefomance Compaison of Each Type of Beaing (boe size 70 mm, DB combination, L peload) High Pecision ACBB Standad Seies 79_C 79_A5 70_C 70_A5 70_A Rotational Speed Radial Rigidity Axial Rigidity Dynamic Load Rating Gease Lubication Oil-ai Lubication Rigidity, N/µm Axial igidity Radial igidity 7020_DB (L peload) Limiting dmn value C (15 ) A5 (25 ) A (30 ) Limiting dmn, 10 4 Beaing tempeatue ise, C Beaing tempeatue LIFE 7020_DB (L peload) C (15 ) A5 (25 ) A (30 ) Rolling fatigue life, h Ulta High-Speed ROBUST Seies 72_C 72_A5 72_A BNR19S BNR19H BNR19X BNR19XE BER19S BER19H BER19X BER19XE BNR10S BNR10H BNR10X BNR10XE BER10S BER10H BER10X The Effect of Peload Peload affects pefomance of ACBBs in much the same way that the contact angle does. As peload inceases, the igidity inceases but the speed capability deceases. NSK has defined standad peload levels as Exta Light (EL), Light (L), Medium (M) and Heavy (H). The figue below compaes the pefomance of a 7020CDB with each peload level. Even if the contact angle is held constant, when the peload is lage, both axial and adial igidity ae inceased. Howeve the tempeatue also ises, so the limiting speed and calculated life become lowe. In ode to maintain high igidity, it is necessay to sacifice highe speed. Similaly to accomplish highe speed, it is necessay to sacifice high igidity. Caution must be execised. If too high a peload is combined with high opeation speed, thee is a possibility of seizue. Rigidity, N/µm Axial igidity Radial igidity Limiting dmn value CDB (Contact angle 15 ) L peload M peload H peload The Effect of Combination Limiting dmn, 10 4 Beaing tempeatue ise, C Beaing tempeatue LIFE 7020CDB (Contact angle 15 ) L peload M peload H peload Rolling fatigue life, h Thust ACBB BER10XE BAR10S BAR10H BTR10S BTR10H (min 1 ) (N/µm) (N/µm) (kn) ACBBs ae usually used as multiple beaing sets. Thee ae thee types of combinations Back-to-Back (DB), Face-to-Face (DF) and Tandem (DT). Two ow, thee ow, and fou ow ae the most popula multiple beaing sets. When the combination is held constant, and the numbe of ows is inceased, the igidity and the load capacity become lage, but the limiting speed becomes lowe. Rigidity, N/µm Axial igidity Radial igidity Limiting dmn value C_L (peload) Single ow DB DBD DBB Limiting dmn,

24 FEATURES OF CYLINDRICAL ROLLER BEARINGS Pat 1 Pat 2 Pat3 Pat 4 Pat 5 Pat 6 Pat 7 Pat 8 Cylindical Rolle Beaing (CRB) Cylindical olle beaings suppot only adial loads, but have the advantage of a lage adial load capacity ating than ACBBs. Double ow cylindical olle beaings (NN and NNU types) and single ow cylindical beaings (N type) ae available. In geneal, double ow cylindical olle beaings ae used fo high igidity applications such as lathes, while single ow cylindical olle beaings ae used in high-speed applications such as machining centes. The following gaphs display cylindical olle beaing pefomance depending on the type of beaing (by seies and dimensional seies) and the adial cleaance involved. Pefomance Compaison Relative to CRB Type: (boe size 100 mm) Double Row CRB High Rigidity Seies NN3020MB NN3020TB NN3920MB NN4920MB Rotational Speed Gease Lubication Oil-ai Lubication Radial Rigidity Dynamic Load Rating The Effect of the Radial Cleaance When using cylindical olle beaings, it is impotant to contol the adial cleaance since it will have the geatest impact on beaing pefomance. As the adial cleaance inceases, both igidity and calculated fatigue life decease. With highe adial cleaances heat geneation duing opeation also deceases. Convesely, as the figue below illustates, igidity is not inceased if the adial cleaance dops below mm, while the calculated fatigue life continues to decease. Theefoe, the optimum cleaance taget to achieve high igidity and long life is zeo o just slightly negative cleaance. Fo applications involving high speed, it is necessay to contol the cleaance duing opeation. Popely adjusting the adial cleaance when the beaing is installed to compensate fo the effects of high speed opeation does this. Radial displacement, mm Beaing Rigidity Radial cleaance, mm Beaing: NN3020MBKR Radial load: N Life atio Life Ratio Radial cleaance, mm Beaing: NN3020MBKR Radial load: N NNU4920MB The Relationship Between Radial Cleaance and Tempeatue Rise Single Row CRB Standad Seies N1020MR (min 1 ) (N/µm) (kN) Pefomance Compaison Relative to CRB Type: (boe size 70 mm ) Rotational Speed Radial Rigidity Dynamic Load Rating The figue at the ight shows test esult of the tempeatue ise of CRB. Afte-mounted Radial Cleaance Beaing (1): 0 µm Beaing (2): 30 µm The tempeatue ise of beaing (2) is lage and the limiting speed is lowe than beaing (1), clealy demonstating the impotance of popely contolling the cleaance. Oute ing tempeatue ise, C Beaing numbe: N1014 (oute and inne ings and olles: SHX) (1): Cleaance afte mounted: 0 µm, Gease lubication (NBU15) (2): Cleaance afte mounted: 30 µm Discontinued Speed, min 1 Double Row CRB High Rigidity Seies NN3014MB NN3014TB Gease Lubication Oil-ai Lubication A CRB with a tapeed boe is used to contol adial cleaance duing spindle assembly because it is easy to adjust the adial cleaance to any value. Fo a CRB with a tapeed boe, the popula unmounted nonintechangeable adial cleaance classes ae CC9, CC0, and CC1. The specific featues of each ae outlined below. Single Row CRB Standad Seies N1014MR NSK s ecommended cleaance CC0 Matched cleaance ange less than CC1. This ange ovelaps with the uppe values of CC9 and lowe values of CC1. As this cleaance is easy fo customes to taget this ange, it is the ecommended cleaance offeed fo CRB with tape boe. Ulta High-speed Single Row CRB ROBUST Seies N1014RS N1014RX N1014RXH (min 1 ) (N/µm) (kN) CC1 cleaance Matched cleaance ange is geate than CC0. While not the standad, this cleaance is most popula in the field. When cleaance is at its maximum, special cae is equied to accomodate expansion of the inne ing. If cae is not used, and the spindle s coss-section is thin, defomation of the beaing o shaft may occu. CC9 cleaance Matched cleaance ange is less than CC0. This cleaance will help avoid potential defomation of the inne ing o the shaft when thee is little toleance fo inne ing expansion. Since the adial cleaance is educed to the minimum, the intefeence between the inne ing and the shaft becomes small. In high speed applications, this may cause loosening of the inne ing fom the shaft and esult in some ceep damage

25 1. ANGULAR CONTACT BALL BEARINGS Pat4 High Pecision Angula Contact Ball Beaings Standad Seies Ulta High-Speed Angula Contact Ball Beaings ROBUST Seies Ulta High-Speed Angula Contact Ball Beaings Spinshot TM II Ulta High Pecision Angula Contact Ball Beaings BGR Seies Angula Contact Ball Beaings 1High Pecision Angula Contact Ball Beaings (Standad Seies) P48-60 Featues Numbeing System Beaing Tables Miniatue Seies, BSA Seies fo Ball Scew Suppot 79 Seies 70 Seies 72 Seies Ulta High-Speed Angula Contact Ball Beaings (ROBUST Seies) P62-79 Featues Numbeing System Beaing Tables BNR19, BER19 Seies BNR10, BER10 Seies BNR19XE/10XE, BER19XE/10XE Seies (Spinshot II) BNR29, BER29 Seies (Wide Seies) BNR20, BER20 Seies (Wide Seies) Ulta High Pecision Angula Contact Ball Beaings (ROBUST Seies BGR) P80-84 Featues Numbeing System Beaing Tables BGR19 Seies BGR10 Seies BGR02 Seies Angula Contact Ball Beaings Angula Contact Ball Beaings 46 47

26 1. ANGULAR CONTACT BALL BEARINGS High Pecision Angula Contact Ball Beaings (Standad Seies) Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Featues Single-ow angula contact ball beaings have a line connecting the contact points dawn in the adial diection, which is called the contact angle. The contact angle makes this beaing suitable fo accommodating adial loads, single diection axial loads, and a combination of both. Futhemoe, since an axial component is geneated when a adial load is applied, these beaings ae geneally used in pais, tiplex sets, quaduplex sets, o multiplex sets. Contact Angle Fig. 1.2 Ball diamete F a / Numbe of balls F a Contact point 30 Load acting on olling element 30 contact angle Dimension Seies F a / Numbe of balls F a Contact point 15 Load acting on olling element 15 contact angle Fig. 1.1 F a Contact angle Effective load cente F When a load is applied to an angula contact ball beaing, elastic defomation and the amount of stess at the contact point changes as a esult of the vaying load conditions of the balls, inne ing, and oute ing accoding to the contact angle of the beaing. Figue 1.2 illustates loads acting on two olling elements fo a 30 contact angle, and a 15 contact angle. The elation between an axial load being applied to the beaing and esulting load acting on the olling element can be fomulated as: Fa/(Numbe of balls sinα). Theefoe, the lage the contact angle, the smalle the load acting on the olling element. Load at the contact point, and its consequential defomation, is educed thus esulting in longe life. When a adial load is applied, the smalle the contact angle, the smalle the load acting on the olling element, thus esulting in educed load at the contact point. (See Pages 42 and 43 fo contact angle specifics.) Numbeing System of High Pecision Angula Contact Ball Beaings (Standad Seies) Refeence pages 7 Beaing type 7: single-ow angula contact ball beaing 42-43, 48 0 Dimension 9: 19 seies, 0: 10 seies, 2: 02 seies 42-43, Boe numbe Less than 03, Beaing boe 00: 10 mm, 01: 12 mm 02: 15 mm, 03: 17 mm Ove 04, Beaing boe Boe numbe 5 (mm) C Contact angle C: 15, A5: 25, A: , 48 TYN DB (Beaing numbe example) Beaing type symbol Dimension symbol Boe numbe Contact angle symbol Mateial symbol Mateial No symbol: beaing steel (SUJ2) SN24: ceamic ball (Si 3 N 4 ) ( 1 ) Cage TYN: ball guided polyamide esin cage; limiting speed d m n = ; opeational tempeatue limit = 120 C TR: oute ing guided phenolic esin cage; opeational tempeatue limit = 120 C Seal No symbol: open type V1V: non-contact ubbe seal ( 2 ) 32 Aangement C TYN DB L P4 Accuacy symbol Peload symbol Aangement symbol Seal symbol Cage symbol SU: univesal aangement (single ow) DU: univesal aangement (double ow) DB: Back-to-back aangement DF: Face-to-face aangement DT: tandem aangement DBD, DFD, DTD, DUD: tiplex set aangement DBB, DFF, DBT, DFT, DTT, QU: quaduplex set aangement Standad Angula Contact Ball Beaings Fig. 1.3 L Peload EL: exta light peload, L: light peload, M: medium peload, H: heavy peload CP: special peload, CA: special axial cleaance P4 Accuacy P2: ISO Class 2, P4: ISO Class 4, P5: ISO Class 5 P3: special class (dimensional accuacy: ISO Class 4; otating accuacy: ISO Class 2) P4Y: special class (Boe diamete and outside diamete ae exclusive to NSK. All othes ae ISO Class 4.) ( 1 ) Angula contact ceamic ball beaing coespondence numbes 79, 70: Boe diamete= mm. ( 2 ) Sealed angula contact ball beaings ae standadized fo SU aangement and ISO Class 3. Sealed angula contact ball beaing coespondence numbes 79, 70: Boe diamete= mm

27 1. ANGULAR CONTACT BALL BEARINGS High Pecision Angula Contact Ball Beaings (Miniatue Seies) 70 Seies 72 Seies Boe Diamete 5-8 mm Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (g) (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) (mm) (min.) (min.) (Dynamic) (Static) (kn) a (appox.) Gease Oil 725C A C A C A C A C A C A ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. When a ceamic ball is used, limiting speed value will be 1.25 times the value of steel ball. Note: Beaing numbes with a C suffix: nominal contact angle 15 Beaing numbes with an A suffix: nominal contact angle 30 High Pecision Angula Contact Ball Beaings (BSA Seies fo ball scew suppot) 10 Seies Boe Diamete 8-15 mm D D 1 B a B a 1 d d 79 Seies Boe Diamete mm Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 High Pecision Angula Contact Ball Beaings (Standad Seies) Fo additional infomation: Page No. Dynamic equivalent load 139 Static equivalent load 146 Peload and igidity 152 Abutment and fillet dimensions 186 Nozzle position 192 Quantity of packed gease 175 Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Facto Cente (kg) Sealed (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) f 0 (mm) (appox.) Design (min.) (min.) (Dynamic) (Static) (kn) a Gease Oil 7900C A C A C A C A C A C A C A C A C A C A C A C A Standad Angula Contact Ball Beaings 50 Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (g) (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) (mm) (min.) (min.) (Dynamic) (Static) (kn) a (appox.) Gease 8BSA10T1X BSA10T1X BSA10T1X BSA10T1X ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. When a ceamic ball is used, limiting speed value will be 1.25 times the value of steel ball. Note: Beaing type BSA: nominal contact angle 30 ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. When a ceamic ball is used, limiting speed value will be 1.25 times the value of steel ball. Note: Beaing numbes with a C suffix: nominal contact angle 15 Beaing numbes with an A5 suffix: nominal contact angle 25 51

28 1. ANGULAR CONTACT BALL BEARINGS High Pecision Angula Contact Ball Beaings (Standad Seies) 79 Seies Boe Diamete mm Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Facto Cente (kg) Sealed (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) f 0 (mm) (appox.) Design (min.) (min.) (Dynamic) (Static) (kn) a Gease Oil 7912C A C A C A C A C A C A C A C A C A C A C A C A D B a 1 d 79 Seies (continued) Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Fo additional infomation: Page No. Dynamic equivalent load 139 Static equivalent load 146 Peload and igidity 152 Abutment and fillet dimensions 186 Nozzle position 192 Quantity of packed gease 175 Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Facto Cente (kg) Sealed (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) f 0 (mm) (appox.) Design (min.) (min.) (Dynamic) (Static) (kn) a Gease Oil 7926C A C A C A C A C A C A C A C A C A C A C A C A Standad Angula Contact Ball Beaings ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. When a ceamic ball is used, limiting speed value will be 1.25 times the value of steel ball. Note: Beaing numbes with a C suffix: nominal contact angle 15 Beaing numbes with an A5 suffix: nominal contact angle 25 ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing numbes with a C suffix: nominal contact angle 15 Beaing numbes with an A5 suffix: nominal contact angle

29 1. ANGULAR CONTACT BALL BEARINGS High Pecision Angula Contact Ball Beaings (Standad Seies) 70 Seies Boe Diamete mm Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Facto Cente (kg) Sealed (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) f 0 (mm) (appox.) Design (min.) (min.) (Dynamic) (Static) (kn) a Gease Oil 7000C A A C A A C A A C A A C A A C A A C A A C A A D B a 1 d 70 Seies (continued) Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Fo additional infomation: Page No. Dynamic equivalent load 139 Static equivalent load 146 Peload and igidity 152 Abutment and fillet dimensions 186 Nozzle position 192 Quantity of packed gease 175 Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Facto Cente (kg) Sealed (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) f 0 (mm) (min.) (min.) (Dynamic) (Static) (kn) a (appox.) Design Gease Oil 7008C A A C A A C A A C A A C A A C A A C A A C A A Standad Angula Contact Ball Beaings ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. When a ceamic ball is used, limiting speed value will be 1.25 times the value of steel ball. Note: Beaing numbes with a C suffix: nominal contact angle 15 Beaing numbes with an A5 suffix: nominal contact angle 25 Beaing numbes with an A suffix: nominal contact angle 30 ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. When a ceamic ball is used, limiting speed value will be 1.25 times the value of steel ball. Note: Beaing numbes with a C suffix: nominal contact angle 15 Beaing numbes with an A5 suffix: nominal contact angle 25 Beaing numbes with an A suffix: nominal contact angle

30 1. ANGULAR CONTACT BALL BEARINGS High Pecision Angula Contact Ball Beaings (Standad Seies) 70 Seies Boe Diamete mm Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Facto Cente (kg) Sealed (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) f 0 (mm) (appox.) Design (min.) (min.) (Dynamic) (Static) (kn) a Gease Oil 7016C A A C A A C A A C A A C A A C A A C A A C A A D B a 1 d 70 Seies (continued) Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Fo additional infomation: Page No. Dynamic equivalent load 139 Static equivalent load 146 Peload and igidity 152 Abutment and fillet dimensions 186 Nozzle position 192 Quantity of packed gease 175 Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Facto Cente (kg) Sealed (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) f 0 (mm) (min.) (min.) (Dynamic) (Static) (kn) a (appox.) Design Gease Oil 7026C A A C A A C A A C A A C A A C A A C A A C A A Standad Angula Contact Ball Beaings ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. When a ceamic ball is used, limiting speed value will be 1.25 times the value of steel ball. Note: Beaing numbes with a C suffix: nominal contact angle 15 Beaing numbes with an A5 suffix: nominal contact angle 25 Beaing numbes with an A suffix: nominal contact angle 30 ( 1 ) Fo pemissible axial load, please efe to Page 14. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing numbes with a C suffix: nominal contact angle 15 Beaing numbes with an A5 suffix: nominal contact angle 25 Beaing numbes with an A suffix: nominal contact angle

31 58 1. ANGULAR CONTACT BALL BEARINGS High Pecision Angula Contact Ball Beaings (Standad Seies) 72 Seies Boe Diamete mm Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Facto Cente (kg) (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) f 0 (mm) (appox.) (min.) (min.) (Dynamic) (Static) (kn) a Gease Oil 7200C A A C A A C A A C A A C A A C A A C A A C A A C A A C A A C A A ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing numbes with a C suffix: nominal contact angle 15 Beaing numbes with an A5 suffix: nominal contact angle 25 Beaing numbes with an A suffix: nominal contact angle 30 D B a 1 d 72 Seies (continued) Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Facto Cente (kg) (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) f 0 (mm) (appox.) (min.) (min.) (Dynamic) (Static) (kn) a Gease Oil 7211C A A C A A C A A C A A C A A C A A C A A C A A C A A C A A C A A ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing numbes with a C suffix: nominal contact angle 15 Beaing numbes with an A5 suffix: nominal contact angle 25 Beaing numbes with an A suffix: nominal contact angle 30 Fo additional infomation: Page No. Dynamic equivalent load 139 Static equivalent load 146 Peload and igidity 152 Abutment and fillet dimensions 186 Nozzle position 192 Quantity of packed gease 175 Standad Angula Contact Ball Beaings 59

32 1. ANGULAR CONTACT BALL BEARINGS High Pecision Angula Contact Ball Beaings (Standad Seies) B 1 Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 72 Seies Boe Diamete mm Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Facto Cente (kg) (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) f 0 (mm) (appox.) (min.) (min.) (Dynamic) (Static) (kn) a Gease Oil 7222C A A C A A C A A C A A C A A D a d Standad Angula Contact Ball Beaings ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing numbes with a C suffix: nominal contact angle 15 Beaing numbes with an A5 suffix: nominal contact angle 25 Beaing numbes with an A suffix: nominal contact angle

33 1. ANGULAR CONTACT BALL BEARINGS Ulta High-Speed Angula Contact Ball Beaings (ROBUST Seies) Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Featues Optimum Design Long Life Robust design achieved with NSK s popietay analytical technology. Optimum design achieved by compute simulation of tempeatue ise esulting fom ball skid. New SHX steel mateial povides supeio heat and wea esistance. Enhanced sevice life measues include aising the seizue limit unde low lubication and high-speed opeating conditions. Numbeing System of Ulta High-Speed Angula Contact Ball Beaings (ROBUST Seies) (Beaing numbe example) Nominal beaing boe Beaing type symbol Dimension symbol Mateial symbol 80 BNR 10 H TYN DBB EL P4 Accuacy symbol Peload symbol Aangement symbol Seal symbol Cage symbol ROBUST Angula Contact Ball Beaings High Accuacy Rolling element mateial can be tailoed to match the application. Ceamic balls ae used fo ROBUST seies angula contact ball beaings. Highly accuate P2 seies is available. NSK s expeience and know-how ensue beaing specifications with a high degee of accuacy. Refeence pages 80 Nominal beaing boe Boe diamete (mm) BNR Beaing type BNR: 18 contact angle, BER: 25 contact angle 42-43, Dimension 10: 10 seies, 19: 19 seies, 20: 20 seies, 29: 29 seies ( 1 ) 42-43, 62 High Speed Cage engineeed fo high-speed opeations. Benefits of the lightweight, high stength engineeed esin cage include heat esistance and high igidity, making this cage indispensable fo high-speed applications. Type Rings Mateial Rolling elements H Mateial S Beaing steel (SUJ2) Beaing steel (SUJ2) H Beaing steel (SUJ2) Ceamics (Si 3 N 4 ) Low Noise Quiete unning high-speed spindle featuing Spinshot TM II lubication system. Eliminates noise caused by compessed ai of the oil-ai lubication system. X Heat esistant steel (SHX) Ceamics (Si 3 N 4 ) XE (Spinshot TM II) Heat esistant steel (SHX) Ceamics (Si 3 N 4 ) TYN Cage TYN: ball guided polyamide esin cage; limiting speed d m n = ; opeational tempeatue limit = 120 C T: phenolic esin cage with oute ing guide; opeational tempeatue limit = 120 C Dimension Seies Seal No symbol: open type V1V: non-contact ubbe seal ( 2 ) 32 Fig. 1.4 DBB Aangement SU: univesal aangement (single ow) DU: univesal aangement (double ow) DB: Back-to-back aangement DF: Face-to-face aangement DT: tandem aangement DBD, DFD, DTD, DUD: tiplex set aangement DBB, DFF, DBT, DFT, DTT, QU: quaduplex set aangement EL Peload EL: exta light peload, L: light peload, M: medium peload, H: heavy peload CP: special peload, CA: special axial cleaance P2: ISO Class 2, P4: ISO Class 4, P5: ISO Class 5 P4 Accuacy P3: special class (dimensional accuacy: ISO Class 4; otating accuacy: ISO Class 2) P4Y: special class (Boe diamete and outside diamete ae exclusive to NSK. All othes ae ISO Class 4.) BNR10 BER10 BNR19 BER19 BNR20 BER20 Seies BNR29 BER29 Seies Spinshot II (XE type) ( 1 ) Seies 20 and 29 ae exclusively fo sealed angula contact ball beaings. ( 2 ) Sealed angula contact ball beaings ae standadized fo SU aangement and ISO Class 3 standads. Sealed angula contact ball beaings coespondence numbes BNR19, BNR29, BER19, BER29, BNR10, BNR20, BER10 and BER20: Boe diamete= mm 62 63

34 64 1. ANGULAR CONTACT BALL BEARINGS Ulta High-Speed Angula Contact Ball Beaings (ROBUST Seies) BNR19 Seies BER19 Seies Boe Diamete mm Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (kg) Sealed (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) (mm) (appox.) Design (min.) (min.) (Dynamic) (Static) (kn) a Gease Oil 25BNR19S BNR19H BNR19X BER19S BER19H BER19X BNR19S BNR19H BNR19X BER19S BER19H BER19X BNR19S BNR19H BNR19X BER19S BER19H BER19X BNR19S BNR19H BNR19X BER19S BER19H BER19X BNR19S BNR19H BNR19X BER19S BER19H BER19X BNR19S BNR19H BNR19X BER19S BER19H BER19X ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing type BNR: nominal contact angle 18 Beaing type BER: nominal contact angle 25 D 1 B a 1 d BNR19 Seies (continued) BER19 Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Fo additional infomation: Page No. Dynamic equivalent load 139 Static equivalent load 146 Peload and igidity 152 Abutment and fillet dimensions 186 Nozzle position 192 Quantity of packed gease 175 Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (kg) Sealed (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) (mm) (appox.) Design (min.) (min.) (Dynamic) (Static) (kn) a Gease Oil 55BNR19S BNR19H BNR19X BER19S BER19H BER19X BNR19S BNR19H BNR19X BER19S BER19H BER19X BNR19S BNR19H BNR19X BER19S BER19H BER19X BNR19S BNR19H BNR19X BER19S BER19H BER19X BNR19S BNR19H BNR19X BER19S BER19H BER19X BNR19S BNR19H BNR19X BER19S BER19H BER19X ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing type BNR: nominal contact angle 18 Beaing type BER: nominal contact angle 25 ROBUST Angula Contact Ball Beaings 65

35 1. ANGULAR CONTACT BALL BEARINGS Ulta High-Speed Angula Contact Ball Beaings (ROBUST Seies) BNR19 Seies BER19 Seies Boe Diamete mm Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (kg) Sealed (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) (mm) (appox.) Design (min.) (min.) (Dynamic) (Static) (kn) a Gease Oil 85BNR19S BNR19H BNR19X BER19S BER19H BER19X BNR19S BNR19H BNR19X BER19S BER19H BER19X BNR19S BNR19H BNR19X BER19S BER19H BER19X BNR19S BNR19H BNR19X BER19S BER19H BER19X BNR19S BNR19H BNR19X BER19S BER19H BER19X D 1 B a 1 d BNR19 Seies (continued) BER19 Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (kg) Sealed (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) (mm) (appox.) Design (min.) (min.) (Dynamic) (Static) (kn) a Gease Oil 110BNR19S BNR19H BNR19X BER19S BER19H BER19X BNR19S BNR19H BNR19X BER19S BER19H BER19X BNR19S BNR19H BER19S BER19H BNR19S BNR19H BER19S BER19H BNR19S BNR19H BER19S BER19H ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing type BNR: nominal contact angle 18 Beaing type BER: nominal contact angle 25 Fo additional infomation: Page No. Dynamic equivalent load 139 Static equivalent load 146 Peload and igidity 152 Abutment and fillet dimensions 186 Nozzle position 192 Quantity of packed gease 175 ROBUST Angula Contact Ball Beaings 66 ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing type BNR: nominal contact angle 18 Beaing type BER: nominal contact angle 25 67

36 68 1. ANGULAR CONTACT BALL BEARINGS Ulta High-Speed Angula Contact Ball Beaings (ROBUST Seies) BNR10 Seies BER10 Seies Boe Diamete mm Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (kg) Sealed (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) (mm) (appox.) Design (min.) (min.) (Dynamic) (Static) (kn) a Gease Oil 30BNR10S BNR10H BNR10X BER10S BER10H BER10X BNR10S BNR10H BNR10X BER10S BER10H BER10X BNR10S BNR10H BNR10X BER10S BER10H BER10X BNR10S BNR10H BNR10X BER10S BER10H BER10X BNR10S BNR10H BNR10X BER10S BER10H BER10X ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing type BNR: nominal contact angle 18 Beaing type BER: nominal contact angle 25 D B a 1 d BNR10 Seies (continued) BER10 Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (kg) Sealed (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) (mm) (appox.) Design (min.) (min.) (Dynamic) (Static) (kn) a Gease Oil 55BNR10S BNR10H BNR10X BER10S BER10H BER10X BNR10S BNR10H BNR10X BER10S BER10H BER10X BNR10S BNR10H BNR10X BER10S BER10H BER10X BNR10S BNR10H BNR10X BER10S BER10H BER10X BNR10S BNR10H BNR10X BER10S BER10H BER10X BNR10S BNR10H BNR10X BER10S BER10H BER10X ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing type BNR: nominal contact angle 18 Beaing type BER: nominal contact angle 25 Fo additional infomation: Page No. Dynamic equivalent load 139 Static equivalent load 146 Peload and igidity 152 Abutment and fillet dimensions 186 Nozzle position 192 Quantity of packed gease 175 ROBUST Angula Contact Ball Beaings 69

37 1. ANGULAR CONTACT BALL BEARINGS Ulta High-Speed Angula Contact Ball Beaings (ROBUST Seies) BNR10 Seies BER10 Seies Boe Diamete mm Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (kg) Sealed (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) (mm) (appox.) Design (min.) (min.) (Dynamic) (Static) (kn) a Gease Oil 85BNR10S BNR10H BNR10X BER10S BER10H BER10X BNR10S BNR10H BNR10X BER10S BER10H BER10X BNR10S BNR10H BNR10X BER10S BER10H BER10X BNR10S BNR10H BNR10X BER10S BER10H BER10X BNR10S BNR10H BNR10X BER10S BER10H BER10X D B a 1 d BNR10 Seies (continued) BER10 Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (kg) Sealed (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) (mm) (appox.) Design (min.) (min.) (Dynamic) (Static) (kn) a Gease Oil 110BNR10S BNR10H BNR10X BER10S BER10H BER10X BNR10S BNR10H BNR10X BER10S BER10H BER10X BNR10S BNR10H BER10S BER10H BNR10S BNR10H BER10S BER10H BNR10S BNR10H BER10S BER10H ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing type BNR: nominal contact angle 18 Beaing type BER: nominal contact angle 25 Fo additional infomation: Page No. Dynamic equivalent load 139 Static equivalent load 146 Peload and igidity 152 Abutment and fillet dimensions 186 Nozzle position 192 Quantity of packed gease 175 ROBUST Angula Contact Ball Beaings 70 ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing type BNR: nominal contact angle 18 Beaing type BER: nominal contact angle 25 71

38 1. ANGULAR CONTACT BALL BEARINGS Ulta High-Speed Angula Contact Ball Beaings (Spinshot TM II Seies) BNR19XE Seies BER19XE Seies Boe Diamete mm Bounday Dimensions Spinshot TM Space Dimension Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (mm) (kn) Axial Cente (kg) (min 1 ) Numbes d D B C 1 L 1 L 2 C C 0 Load ( 1 ) (mm) (appox.) (min.) (min.) (appox.) (appox.) (Dynamic) (Static) (kn) a Oil 40BNR19XE BER19XE BNR19XE BER19XE BNR19XE BER19XE BNR19XE BER19XE BNR19XE BER19XE BNR19XE BER19XE BNR19XE BER19XE BNR19XE BER19XE BNR19XE BER19XE BNR19XE BER19XE BNR19XE BER19XE BNR19XE BER19XE BNR19XE BER19XE BNR19XE BER19XE BNR19XE BER19XE L 2 L 1 1 B C a 1 d D BNR10XE Seies BER10XE Seies Boe Diamete mm Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Fo additional infomation: Page No. Dynamic equivalent load 139 Static equivalent load 146 Peload and igidity 152 Shoulde and fillet dimensions 186 Bounday Dimensions Spinshot TM Space Dimension Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (mm) (kn) Axial Cente (kg) (min 1 ) Numbes d D B C 1 L 1 L 2 C C 0 Load ( 1 ) (mm) (appox.) (min.) (min.) (appox.) (appox.) (Dynamic) (Static) (kn) a Oil 40BNR10XE BER10XE BNR10XE BER10XE BNR10XE BER10XE BNR10XE BER10XE BNR10XE BER10XE BNR10XE BER10XE BNR10XE BER10XE BNR10XE BER10XE BNR10XE BER10XE BNR10XE BER10XE BNR10XE BER10XE BNR10XE BER10XE BNR10XE BER10XE BNR10XE BER10XE BNR10XE BER10XE ROBUST Angula Contact Ball Beaings 72 ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing type BNR: nominal contact angle 18 Beaing type BER: nominal contact angle 25 ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing type BNR: nominal contact angle 18 Beaing type BER: nominal contact angle 25 73

39 1. ANGULAR CONTACT BALL BEARINGS Ulta High-Speed Sealed Angula Contact Ball Beaings (Wide Seies) BNR29 Seies BER29 Seies Boe Diamete mm Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (kg) (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) (mm) (appox.) (min.) (min.) (Dynamic) (Static) (kn) a Gease 30BNR29SV1V BNR29HV1V BNR29XV1V BER29SV1V BER29HV1V BER29XV1V BNR29SV1V BNR29HV1V BNR29XV1V BER29SV1V BER29HV1V BER29XV1V BNR29SV1V BNR29HV1V BNR29XV1V BER29SV1V BER29HV1V BER29XV1V BNR29SV1V BNR29HV1V BNR29XV1V BER29SV1V BER29HV1V BER29XV1V BNR29SV1V BNR29HV1V BNR29XV1V BER29SV1V BER29HV1V BER29XV1V ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing type BNR: nominal contact angle 18 Beaing type BER: nominal contact angle 25 D 1 B a d BNR29 Seies (continued) BER29 Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Fo additional infomation: Dynamic equivalent load Page No. 139 Static equivalent load 146 Peload and igidity 152 Abutment and fillet dimensions 186 Nozzle position 192 Quantity of packed gease 175 Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (kg) (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) (mm) (appox.) (min.) (min.) (Dynamic) (Static) (kn) a Gease 55BNR29SV1V BNR29HV1V BNR29XV1V BER29SV1V BER29HV1V BER29XV1V BNR29SV1V BNR29HV1V BNR29XV1V BER29SV1V BER29HV1V BER29XV1V BNR29SV1V BNR29HV1V BNR29XV1V BER29SV1V BER29HV1V BER29XV1V BNR29SV1V BNR29HV1V BNR29XV1V BER29SV1V BER29HV1V BER29XV1V BNR29SV1V BNR29HV1V BNR29XV1V BER29SV1V BER29HV1V BER29XV1V BNR29SV1V BNR29HV1V BNR29XV1V BER29SV1V BER29HV1V BER29XV1V ROBUST Angula Contact Ball Beaings 74 ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing type BNR: nominal contact angle 18 Beaing type BER: nominal contact angle 25 75

40 1. ANGULAR CONTACT BALL BEARINGS Ulta High-Speed Sealed Angula Contact Ball Beaings (Wide Seies) BNR29 Seies BER29 Seies Boe Diamete mm Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (kg) (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) (mm) (appox.) (min.) (min.) (Dynamic) (Static) (kn) a Gease 85BNR29SV1V BNR29HV1V BNR29XV1V BER29SV1V BER29HV1V BER29XV1V BNR29SV1V BNR29HV1V BNR29XV1V BER29SV1V BER29HV1V BER29XV1V BNR29SV1V BNR29HV1V BNR29XV1V BER29SV1V BER29HV1V BER29XV1V BNR29SV1V BNR29HV1V BNR29XV1V BER29SV1V BER29HV1V BER29XV1V ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing type BNR: nominal contact angle 18 Beaing type BER: nominal contact angle 25 D 1 B a d Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Ulta High-Speed Sealed Angula Contact Ball Beaings (Wide Seies) BNR20 Seies BER20 Seies Boe Diamete mm Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (kg) (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) (mm) (appox.) (min.) (min.) (Dynamic) (Static) (kn) a Gease 30BNR20SV1V BNR20HV1V BNR20XV1V BER20SV1V BER20HV1V BER20XV1V BNR20SV1V BNR20HV1V BNR20XV1V BER20SV1V BER20HV1V BER20XV1V BNR20SV1V BNR20HV1V BNR20XV1V BER20SV1V BER20HV1V BER20XV1V BNR20SV1V BNR20HV1V BNR20XV1V BER20SV1V BER20HV1V BER20XV1V BNR20SV1V BNR20HV1V BNR20XV1V BER20SV1V BER20HV1V BER20XV1V D B a 1 d ROBUST Angula Contact Ball Beaings ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing type BNR: nominal contact angle 18 Beaing type BER: nominal contact angle

41 78 1. ANGULAR CONTACT BALL BEARINGS Ulta High-Speed Sealed Angula Contact Ball Beaings (Wide Seies) BNR20 Seies BER20 Seies Boe Diamete mm Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (kg) (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) (mm) (appox.) (min.) (min.) (Dynamic) (Static) (kn) a Gease 55BNR20SV1V BNR20HV1V BNR20XV1V BER20SV1V BER20HV1V BER20XV1V BNR20SV1V BNR20HV1V BNR20XV1V BER20SV1V BER20HV1V BER20XV1V BNR20SV1V BNR20HV1V BNR20XV1V BER20SV1V BER20HV1V BER20XV1V BNR20SV1V BNR20HV1V BNR20XV1V BER20SV1V BER20HV1V BER20XV1V BNR20SV1V BNR20HV1V BNR20XV1V BER20SV1V BER20HV1V BER20XV1V BNR20SV1V BNR20HV1V BNR20XV1V BER20SV1V BER20HV1V BER20XV1V ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing type BNR: nominal contact angle 18 Beaing type BER: nominal contact angle 25 D B a 1 d BNR20 Seies (continued) BER20 Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (kg) (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) (mm) (appox.) (min.) (min.) (Dynamic) (Static) (kn) a Gease 85BNR20SV1V BNR20HV1V BNR20XV1V BER20SV1V BER20HV1V BER20XV1V BNR20SV1V BNR20HV1V BNR20XV1V BER20SV1V BER20HV1V BER20XV1V BNR20SV1V BNR20HV1V BNR20XV1V BER20SV1V BER20HV1V BER20XV1V BNR20SV1V BNR20HV1V BNR20XV1V BER20SV1V BER20HV1V BER20XV1V ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing type BNR: nominal contact angle 18 Beaing type BER: nominal contact angle 25 Fo additional infomation: Dynamic equivalent load Page No. 139 Static equivalent load 146 Peload and igidity 152 Abutment and fillet dimensions 186 Nozzle position 192 Quantity of packed gease 175 ROBUST Angula Contact Ball Beaings 79

42 1. ANGULAR CONTACT BALL BEARINGS Ulta High Pecision Angula Contact Ball Beaings (ROBUST Seies BGR) Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Featues Optimum Design Long Life An oute ing guided cage is used to impove lubication pefomance. The counte-boe inne ing impoves oil-mist flow to ensue a stable oil supply. Special heat esistant SHX steel and ceamic balls significantly impove sevice life (X-type beaings). Numbeing System of Ulta High Pecision Angula Contact Ball Beaings (ROBUST Seies BGR) (Beaing numbe example) Nominal beaing boe Beaing type symbol Dimension symbol Mateial symbol 8 BGR 10 S T DU EL P2 Accuacy symbol Peload symbol Aangement symbol Cage symbol BGR Angula Contact Ball Beaings Easy Mounting Non-sepaable inne ing design geatly simplifies mounting and dismounting pocedues. Intechangeable assembly fo any desied aangement to meet custome needs. Refeence pages 8 Nominal beaing boe Boe diamete (mm) High Accuacy BGR Seies ae standadized fo ISO Class 2 (ABMA ABEC 9). BGR Beaing type BGR: 15 contact angle 42-43, Dimension 10: 10 seies, 19: 19 seies, 02: 02 seies 42-43, 80 Dimension Seies S Mateial Mateial Type Rings Rolling elements S Beaing steel (SUJ2) Beaing steel (SUJ2) H Beaing steel (SUJ2) Ceamics (Si 3 N 4 ) Fig. 1.5 X Heat esistant steel (SHX) Ceamics (Si 3 N 4 ) T Cage T: phenolic esin cage with oute ing guide; opeational tempeatue limit = 120 C DU Aangement SU: univesal aangement (single ow) DU: univesal aangement (double ow) EL Peload EL: exta light peload , 165 BGR02 BGR10 BGR19 P2 Accuacy P2: ISO Class 2, P4: ISO Class 4 P3: special class (dimensional accuacy: ISO Class 4; otating accuacy: ISO Class 2)

43 1. ANGULAR CONTACT BALL BEARINGS Ulta High Pecision Angula Contact Ball Beaings (ROBUST Seies BGR) BGR19 Seies Boe Diamete mm Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (kg) (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) (mm) (min.) (min.) (Dynamic) (Static) (kn) a (appox.) Gease Oil 10BGR19S BGR19H BGR19X BGR19S BGR19H BGR19X BGR19S BGR19H BGR19X BGR19S BGR19H BGR19X BGR19S BGR19H BGR19X BGR19S BGR19H BGR19X ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing type BGR: nominal contact angle 15 D 1 B a 1 d BGR10 Seies Boe Diamete 6-25 mm Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Fo additional infomation: Page No. Dynamic equivalent load 139 Static equivalent load 146 Peload and igidity 152 Abutment and fillet dimensions 186 Nozzle position 192 Quantity of packed gease 175 Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (kg) (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) (mm) (min.) (min.) (Dynamic) (Static) (kn) a (appox.) Gease Oil 6BGR10S BGR10H BGR10X BGR10S BGR10H BGR10X BGR10S BGR10H BGR10X BGR10S BGR10H BGR10X BGR10S BGR10H BGR10X BGR10S BGR10H BGR10X BGR10S BGR10H BGR10X BGR10S BGR10H BGR10X BGR10S BGR10H BGR10X BGR Angula Contact Ball Beaings ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing type BGR: nominal contact angle

44 1. ANGULAR CONTACT BALL BEARINGS Ulta High Pecision Angula Contact Ball Beaings (ROBUST Seies BGR) B 1 Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 BGR02 Seies Boe Diamete mm Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (kg) (min 1 ) Numbes d D B 1 C C 0 Load ( 1 ) (mm) (appox.) (min.) (min.) (Dynamic) (Static) (kn) a Gease Oil 10BGR02S BGR02H BGR02X BGR02S BGR02H BGR02X BGR02S BGR02H BGR02X BGR02S BGR02H BGR02X BGR02S BGR02H BGR02X BGR02S BGR02H BGR02X D 1 a d BGR Angula Contact Ball Beaings ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Note: Beaing type BGR: nominal contact angle

45 2. CYLINDRICAL ROLLER BEARINGS Pat4 Double-Row Cylindical Rolle Beaings High Rigidity Seies Single-Row Cylindical Rolle Beaings Standad Seies Ulta High-Speed Single-Row Cylindical Rolle Beaings ROBUST Seies Cylindical Rolle Beaings Cylindical Rolle Beaings P88-97 Featues Numbeing System Beaing Tables Double-Row Cylindical Rolle Beaings (High Rigidity Seies) 30 Seies 39 Seies 49 Seies Single-Row Cylindical Rolle Beaings (Standad Seies) 10 Seies Ulta High-Speed Single-Row Cylindical Rolle Beaings (ROBUST Seies) 10 Seies Double-Row Cylindical Rolle Beaings (Low Heat Geneation Seies) 30 Seies Ulta High-Speed Single-Row Cylindical Rolle Beaings (Low Heat Geneation Seies) 10 Seies Cylindical Rolle Beaings Cylindical Ro lle Beaings 86 87

46 2. CYLINDRICAL ROLLER BEARINGS Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Featues The high igidity of NSK s double-ow cylindical olle beaings makes them a pefect match fo use in machine tool spindles. Typically, single-ow and double-ow cylindical olle beaings have eithe a cylindical boe o a tapeed boe. Double-ow cylindical olle beaings with a tapeed boe ae often mounted to the main shaft as a fixed-end beaing. Simplicity in design and the ability to adjust adial intenal cleaance afte mounting continue to make these beaings popula among machine tool uses. NSK offes seveal types of cylindical olle beaings. Uses can equest an E44 configuation, which includes both lubication holes and a machined lubication goove on the outside suface of the oute ing. Types of beaings include the NNU type, which featues double ibbed oute ings, and the NN type, which featues excellent gease dischage duing the initial unning-in peiod, and helps pomote steady oil flow thoughout the beaing. Fo thin section type beaings, the naowe NN39 seies is moe suitable than the wide NN49 seies due to less heat geneation and geate olle stability. Machined bass cages ae most common with cylindical olle beaings. NSK offes a olle guided PPS (polyphenylene sulfide) esin cage fo the NN30 seies, and a PEEK (polyethe ethe ketone) esin cage, which is guided by the oute ing, fo N10 seies of ulta high-speed single-ow cylindical olle beaings. Specification of Boe and Lubication Holes Fig. 2.1 Beaing type Cage symbol Specification Available size NN3005, NN3026-NN3040 NN MB Rolle guided machined bass cage NN3920-NN3956 NN4920-NN4940 TB Rolle guided PPS esin cage NN3006-NN3024 NNU MB Rolle guided machined bass cage NNU4920-NNU4940 N MR Rolle guided machined bass cage N1006-N1028 TP Oute ing guided PEEK esin cage N1009-N1017 Numbeing System of Double-Row Cylindical Rolle Beaings (High Rigidity Seies) (Beaing numbe example) Beaing type symbol Dimension symbol Boe numbe Intenal symbol Cage symbol NN TB KR E44 CC0 P4 Accuacy symbol Radial cleaance symbol Lubication holes symbol Tapeed boe symbol Refeence pages NN Beaing type NN: double-ow cylindical olle beaing with tiple-ibbed inne ing, NNU: double-ow cylindical olle beaing with tiple-ibbed oute ing 44-45, Dimension 30: 30 seies, 39: 39 seies, 49: 49 seies 44-45, Boe numbe Beaing boe = boe numbe 5 (mm) Z Intenal symbol No symbol: standad type Z: low heat geneation type 96 TB Cage TB: olle guided PPS esin cage; opeational tempeatue limit = 220 C MB: olle guided machined bass cage; opeational tempeatue limit = 300 C KR Tapeed boe KR: 1/12 tapeed boe (Leave this symbol blank fo cylindical boe) E44 Lubication holes E44: oute ing with machined lubication goove and lubication holes (Leave this symbol blank fo no lubication holes) CC0 P4 Radial cleaance Accuacy CC1: standad cleaance fo cylindical boe CC0: standad cleaance fo tapeed boe CCG: special adial cleaance P2: ISO Class 2, P4: ISO Class 4, P4Y: special class (Boe diamete and outside diamete ae exclusive to NSK. All othes ae ISO Class 4.) Numbeing System of Single-Row Cylindical Rolle Beaings (Standad Seies and ROBUST Seies) Cylindical Rolle Beaings (Beaing numbe example) Beaing type symbol Dimension symbol Boe numbe Mateial symbol Intenal symbol N RX TP KR CC0 P4 Accuacy symbol Radial cleaance symbol Tapeed boe symbol Cage symbol Cylindical boe type Tapeed boe type Machined lubication goove on outside suface and lubication holes on the oute ing (E44) Double-ow and single-ow beaings available with cylindical boe o tapeed boe. Double-ow cylindical olle beaings available with a machined lubication goove and lubication holes (the best solution fo oil lubication). Beaing Type and Dimension Seies Fig. 2.2 N Beaing type N: single-ow cylindical olle beaing with double-ibbed inne ing 44-45, Dimension 10: 10 seies 44-45, Boe numbe Beaing boe = boe numbe 5 (mm) RX Mateial No symbol indicates ou standad cylindical olle beaing mateial (ings and olling elements ae SUJ2 beaing steel). RS RX RXH: ulta high-speed single-ow cylindical olle beaing (ROBUST seies) Type Mateial Rings Rolling elements RS Beaing steel (SUJ2) Beaing steel (SUJ2) RX Heat esistant steel (SHX) Heat esistant steel (SHX) RXH Heat esistant steel (SHX) Ceamics (Si 3 N 4 ) Refeence pages N10 NN30 NN39 NN49 NNU49 Z Intenal symbol No symbol: Standad type Z: Low heat geneation type 97 TP Cage TP: oute ing guided PEEK esin cage; opeational tempeatue limit = 240 C MR: olle guided machined bass cage; opeational tempeatue limit = 300 C KR Tapeed boe KR: 1/12 tapeed boe (Leave this symbol blank fo cylindical boe) CC1: standad cleaance fo cylindical boe Radial CC0: standad cleaance fo tapeed boe cleaance CCG: special adial cleaance 169 CC0 P4 Accuacy P2: ISO Class 2, P4: ISO Class 4, P4Y: special class (Boe diamete and outside diamete ae exclusive to NSK. All othes ae ISO Class 4.)

47 2. CYLINDRICAL ROLLER BEARINGS Double-Row Cylindical Rolle Beaings (High Rigidity Seies) B Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 B 30 Seies Boe Diamete mm D d D d Cylindical Boe 30 Seies (continued) Tapeed Boe Bounday Dimensions Basic Load Ratings Cicumscibed Mass Limiting Speeds ( 1 ) Beaing (mm) (kn) cicle diamete (kg) (min 1 ) Numbes C d D B C 0 of olle (Dynamic) (Static) (mm) (efeence) (appox.) Gease Oil NN3005MBKR NN3006MBKR NN3006TBKR NN3007MBKR NN3007TBKR NN3008MBKR NN3008TBKR NN3009MBKR NN3009TBKR NN3010MBKR NN3010TBKR NN3011MBKR NN3011TBKR NN3012MBKR NN3012TBKR NN3013MBKR NN3013TBKR NN3014MBKR NN3014TBKR NN3015MBKR NN3015TBKR NN3016MBKR NN3016TBKR NN3017MBKR NN3017TBKR ( 1 ) Fo application of limiting speeds, please efe to Page 170. Fo the cylindical boe type, eliminate the KR symbol and leave this symbol blank. Bounday Dimensions Basic Load Ratings Cicumscibed Mass Limiting Speeds ( 1 ) Beaing (mm) (kn) cicle diamete (kg) (min 1 ) Numbes C d D B C 0 of olle (Dynamic) (Static) (mm) (efeence) (appox.) Gease Oil NN3018MBKR NN3018TBKR NN3019MBKR NN3019TBKR NN3020MBKR NN3020TBKR NN3021MBKR NN3021TBKR NN3022MBKR NN3022TBKR NN3024MBKR NN3024TBKR NN3026MBKR NN3028MBKR NN3030MBKR NN3032MBKR NN3034MBKR NN3036MBKR NN3038MBKR NN3040MBKR ( 1 ) Fo application of limiting speeds, please efe to Page 170. Lubication Holes Dimensions (E44 Specification) Unit: mm Oute Ring Width Lubication Hole Machined Numbe of Holes Lubication Goove ove incl. dh W m W m-dh Fo additional infomation: Page No. Dynamic equivalent load 139 Static equivalent load 146 Radial cleaance 169 Abutment and fillet dimensions 186 Nozzle position 192 Quantity of packed gease 175 Double Row Cylindical Rolle Beaings

48 2. CYLINDRICAL ROLLER BEARINGS Double-Row Cylindical Rolle Beaings (High Rigidity Seies) B B B Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 B B B 39 Seies Boe Diamete mm 49 Seies Boe Diamete mm D d D d D *NN39 Cylindical Boe NN39 Tapeed Boe NN49 Cylindical Boe NN49 Tapeed Boe *NNU49 Cylindical Boe d D d D d D NNU49 Tapeed Boe d Bounday Dimensions Basic Load Ratings Cicumscibed Mass Limiting Speeds ( 1 ) Beaing (mm) (kn) cicle diamete (kg) (min 1 ) Numbes C d D B C 0 of olle (Dynamic) (Static) (mm) (efeence) (appox.) Gease Oil NN3920MBKR NN3921MBKR NN3922MBKR NN3924MBKR NN3926MBKR NN3928MBKR NN3930MBKR NN3932MBKR NN3934MBKR NN3936MBKR NN3938MBKR NN3940MBKR NN3944MBKR NN3948MBKR NN3952MBKR NN3956MBKR ( 1 ) Fo application of limiting speeds, please efe to Page 170. *Fo the cylindical boe type, eliminate the KR symbol and leave this symbol blank. Bounday Dimensions Basic Load Ratings Cicumscibed cicle Mass Limiting Speed ( 1 ) diamete of olle Beaing (mm) (kn) (mm) (efeence) (kg) (min 1 ) Numbes C d D B C (inscibed cicle 0 diamete in the case (Dynamic) (Static) (appox.) Gease Oil of NNU type) NN4920MBKR NNU4920MBKR NN4921MBKR NNU4921MBKR NN4922MBKR NNU4922MBKR NN4924MBKR NNU4924MBKR NN4926MBKR NNU4926MBKR NN4928MBKR NNU4928MBKR NN4930MBKR NNU4930MBKR NN4932MBKR NNU4932MBKR NN4934MBKR NNU4934MBKR NN4936MBKR NNU4936MBKR NN4938MBKR NNU4938MBKR NN4940MBKR NNU4940MBKR Double Row Cylindical Rolle Beaings Lubication Holes Dimensions (E44 Specification) Oute Ring Width Lubication Hole Machined Numbe of Holes Lubication Goove ove incl. dh W m Unit: mm W m-dh Fo additional infomation: Page No. Dynamic equivalent load 139 Static equivalent load 146 Radial cleaance 169 Abutment and fillet dimensions 186 Nozzle position 192 Quantity of packed gease 175

49 2. CYLINDRICAL ROLLER BEARINGS Single-Row Cylindical Rolle Beaings (Standad Seies) 10 Seies Boe Diamete mm D B 1 Cylindical Boe d D B 1 Tapeed Boe d Ulta High-Speed Single-Row Cylindical Rolle Beaings (ROBUST Seies) B B 10 Seies Boe Diamete mm Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 D 1 Cylindical Boe d D Tapeed Boe 1 d Fo additional infomation: Page No. Dynamic equivalent load 139 Static equivalent load 146 Radial cleaance 169 Abutment and fillet dimensions 186 Nozzle position 192 Quantity of packed gease 175 Bounday Dimensions Basic Load Ratings Cicumscibed Mass Limiting Speeds ( 1 ) Beaing (mm) (kn) cicle diamete (kg) (min 1 ) Numbes C d D B C 0 of olle 1 (Dynamic) (Static) (mm) (efeence) (appox.) Gease Oil N1006MR1KR N1007MRKR N1008MRKR N1009MRKR N1010MRKR N1011BMR1KR N1012BMR1KR N1013BMR1KR N1014BMR1KR N1015MRKR N1016BMR1KR N1017BMR1KR N1018MRKR N1019BMR1KR N1020MRKR N1021MRKR N1022BMR1KR N1024MRKR N1026MRKR N1028BMR1KR ( 1 ) Fo application of limiting speeds, please efe to Page 170. Fo the cylindical boe type, eliminate the KR symbol and leave this symbol blank. Bounday Dimensions Basic Load Ratings Cicumscibed Mass Limiting Speeds ( 1 ) Beaing (mm) (kn) cicle diamete (kg) (min 1 ) Numbes C d D B C 0 of olle 1 (Dynamic) (Static) (mm) (efeence) (appox.) Gease Oil N1009RSTPKR N1009RXTPKR N1009RXHTPKR N1010RSTPKR N1010RXTPKR N1010RXHTPKR N1011RSTPKR N1011RXTPKR N1011RXHTPKR N1012RSTPKR N1012RXTPKR N1012RXHTPKR N1013RSTPKR N1013RXTPKR N1013RXHTPKR N1014RSTPKR N1014RXTPKR N1014RXHTPKR N1015RSTPKR N1015RXTPKR N1015RXHTPKR N1016RSTPKR N1016RXTPKR N1016RXHTPKR N1017RSTPKR N1017RXTPKR N1017RXHTPKR Single Row Cylindical Rolle Beaings ( 1 ) Fo application of limiting speeds, please efe to Page 170. Fo the cylindical boe type, eliminate the KR symbol and leave this symbol blank

50 2. CYLINDRICAL ROLLER BEARINGS Double-Row Cylindical Rolle Beaings (Low Heat Geneation Seies) 30 Seies Boe Diamete mm D B d D B d Fo additional infomation: Page No. Dynamic equivalent load 139 Static equivalent load 146 Radial cleaance 169 Abutment and fillet dimensions 186 Nozzle position 192 Quantity of packed gease 175 Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Ulta High-Speed Single-Row Cylindical Rolle Beaings (Low Heat Geneation Seies) 10 Seies Boe Diamete mm D B 1 d D B 1 d Fo additional infomation: Page No. Dynamic equivalent load 139 Static equivalent load 146 Radial cleaance 169 Abutment and fillet dimensions 186 Nozzle position 192 Quantity of packed gease 175 Cylindical Boe Tapeed Boe Cylindical Boe Tapeed Boe Bounday Dimensions Basic Load Ratings Cicumscibed Mass Limiting Speeds ( 1 ) Beaing (mm) (kn) cicle diamete (kg) (min 1 ) Numbes C d D B C 0 of olle (Dynamic) (Static) (mm) (efeence) (appox.) Gease Oil NN3006ZTBKR NN3007ZTBKR NN3008ZTBKR NN3009ZTBKR NN3010ZTBKR NN3011ZTBKR NN3012ZTBKR NN3013ZTBKR NN3014ZTBKR NN3015ZTBKR NN3016ZTBKR NN3017ZTBKR NN3018ZTBKR NN3019ZTBKR NN3020ZTBKR NN3021ZTBKR NN3022ZTBKR NN3024ZTBKR ( 1 ) Fo application of limiting speeds, please efe to Page 170. Fo the cylindical boe type, eliminate the KR symbol and leave this symbol blank. Bounday Dimensions Basic Load Ratings Cicumscibed Mass Limiting Speeds ( 1 ) Beaing (mm) (kn) cicle diamete (kg) (min 1 ) Numbes C d D B C 0 of olle (Dynamic) (Static) (mm) (efeence) (appox.) Gease Oil N1009RSZTPKR N1009RXZTPKR N1009RXHZTPKR N1010RSZTPKR N1010RXZTPKR N1010RXHZTPKR N1011RSZTPKR N1011RXZTPKR N1011RXHZTPKR N1012RSZTPKR N1012RXZTPKR N1012RXHZTPKR N1013RSZTPKR N1013RXZTPKR N1013RXHZTPKR N1014RSZTPKR N1014RXZTPKR N1014RXHZTPKR N1015RSZTPKR N1015RXZTPKR N1015RXHZTPKR N1016RSZTPKR N1016RXZTPKR N1016RXHZTPKR N1017RSZTPKR N1017RXZTPKR N1017RXHZTPKR Low Heat Geneation Cylindical Rolle Beaings ( 1 ) Fo application of limiting speeds, please efe to Page 170. Fo the cylindical boe type, eliminate the KR symbol and leave this symbol blank

51 3. ANGULAR CONTACT THRUST BALL BEARINGS Pat4 High-Speed Angula Contact Thust Ball Beaings ROBUST Seies Double-Diection Angula Contact Thust Ball Beaings TAC Seies Angula Contact Thust Ball Beaings Angula Contact Thust Ball Beaings Featues Numbeing System Beaing Tables High-Speed Angula Contact Thust Ball Beaings (ROBUST Seies) BAR10 Seies BTR10 Seies Double-Diection Angula Contact Thust Ball Beaings (TAC Seies) TAC29D Seies TAC20D Seies Angula Contact Thust Ball Beaings Angula Contact Th ust Ball Beaings 98 99

52 3. ANGULAR CONTACT THRUST BALL BEARINGS Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Featues Fo the main spindles of machine tools, good high-speed pefomance and high igidity ae equied fo the ball beaings used in combination with double-ow cylindical olle beaings. Fo these applications, to allow selection appopiate fo the chaacteistics of the machine, NSK povides thee types of beaings. All these beaings have special oute ing outside diamete toleances (P4A Class and P2A Class) to povide cleaance between the oute ing peiphey and housing boe in ode to avoid any load. NSK s ROBUST seies high-speed angula contact thust ball beaings ae capable of high-speed opeations while maintaining high igidity. Ball diamete and numbe of balls ae the same as TAC type beaings. BTR type beaings have a 40 contact angle, and BAR type beaings have a 30 contact angle. The esult is supeio high-speed pefomance that minimizes heat geneation. Intechangeability Customes can easily eplace thei TAC20D seies beaings with NSK s BAR type o BTR type beaings without having to change the shaft o housing of the machine tool spindle. Both types of beaings have unique width dimensions that accommodate a new space D, which eplaces the olde one C (see Fig. 3.1). Fig. 3.1 A C A = 2B D Numbeing System of High-Speed Angula Contact Thust Ball Beaings (ROBUST Seies) Refeence pages 100 Nominal boe diamete Boe diamete (mm) BAR BAR: 30 contact angle Beaing type BTR: 40 contact angle 28, 42-43, Dimension 10: 10 seies (boe, oute diamete, and NSK-specific dimensions ae available) 42-43, 100 Mateial Type S Mateial Rings Rolling elements S Beaing steel (SUJ2) Beaing steel (SUJ2) 14-17, 28 H Beaing steel (SUJ2) Ceamics (Si 3 N 4 ) TYN: ball guided polyamide esin cage; limiting speed d m n = ; opeational tempeatue limit = 120 C TYN (Beaing numbe example) Nominal boe diamete Beaing type symbol Dimension symbol Mateial symbol 100 BAR 10 S TYN DB L P4A Accuacy symbol Peload symbol Aangement symbol Cage symbol Cage Beaing with TYN cage (10 seies with a maximum boe diamete of 150 mm) (Leave this symbol blank fo machined bass cages) DB Aangement DB: Back-to-back aangement 42-43, Angula Contact Thust Ball Beaings L Peload EL: exta light peload, L: light peload CP: special peload, CA: special axial cleaance 42-43, , 166 Contact Angle Fo the diffeing contact angles, TAC type beaings ank highest in levels of igidity, closely followed by BTR type beaings, with BAR type beaings coming in last. Fo tempeatue ise of the oute ing, howeve, this anking is evesed with BAR type beaings having the highest toleance, followed by BTR type beaings, and finally TAC type beaings with the least toleance. Be sue to select the poduct that will best meet the needs of you specific opeating conditions. Fig. 3.2 Fig. 3.3 Axial Load and Axial Displacement P4A Accuacy P2A: ISO Class 2 except oute diamete P4A: ISO Class 4 except oute diamete Numbeing System of Double-Diection Angula Contact Thust Ball Beaings (TAC Seies) (Beaing numbe example) Nominal boe diamete Beaing type symbol 150 TAC 20D PN7 +L C6 Peload symbol Space symbol Accuacy symbol Dimension symbol BAR 40 BTR 60 TAC Axial displacement, µm BAR10S TYN DB (α = 30 ) 100BTR10S TYN DB (α = 40 ) 100TAC20X (α = 60 ) Axial load, N Refeence pages 100 Nominal boe diamete Boe diamete (mm) 105 TAC Beaing type Angula contact thust ball beaing; 60 contact angle 28, 42-43, 100 PN7 Accuacy PN7: special pecision accuacy 182 +L Space Inne ing space D C6 Dimension Peload 20D: combined with NN30 seies 29D: combined with NN39 and NN49 seies C6: standad peload fo gease lubication C7: standad peload fo oil lubication 42-43,

53 3. ANGULAR CONTACT THRUST BALL BEARINGS High-Speed Angula Contact Thust Ball Beaings (ROBUST Seies) BAR10 Seies BTR10 Seies Boe Diamete mm D 1 2B a 1 d BAR10 Seies (continued) BTR10 Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Fo additional infomation: Page No. Dynamic equivalent load 139 Static equivalent load 146 Peload and igidity 152 Abutment and fillet dimensions 186 Nozzle position 192 Quantity of packed gease 175 Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (kg) (min 1 ) Numbes d D 2B 1 C a C 0a Load ( 1 ) (mm) (min.) (min.) (Dynamic) (Static) (kn) a (appox.) Gease Oil 50BAR10S BAR10H BTR10S BTR10H BAR10S BAR10H BTR10S BTR10H BAR10S BAR10H BTR10S BTR10H BAR10S BAR10H BTR10S BTR10H BAR10S BAR10H BTR10S BTR10H BAR10S BAR10H BTR10S BTR10H Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (kg) (min 1 ) Numbes d D 2B 1 C a C 0a Load ( 1 ) (mm) (min.) (min.) (Dynamic) (Static) (kn) a (appox.) Gease Oil 80BAR10S BAR10H BTR10S BTR10H BAR10S BAR10H BTR10S BTR10H BAR10S BAR10H BTR10S BTR10H BAR10S BAR10H BTR10S BTR10H BAR10S BAR10H BTR10S BTR10H BAR10S BAR10H BTR10S BTR10H ROBUST Angula Contact Thust Ball Beaings ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Limiting speeds listed on this page ae based on a back-to-back aangement (DB) with exta light peload (EL). Adjust the limiting speed to 85% of the figue shown when a light peload (L) has been selected. Note: Beaing type BAR10: nominal contact angle 30 Beaing type BTR10: nominal contact angle 40 ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Limiting speeds listed on this page ae based on a back-to-back aangement (DB) with exta light peload (EL). Adjust the limiting speed to 85% of the figue shown when a light peload (L) has been selected. Note: Beaing type BAR10: nominal contact angle 30 Beaing type BTR10: nominal contact angle

54 3. ANGULAR CONTACT THRUST BALL BEARINGS High-Speed Angula Contact Thust Ball Beaings (ROBUST Seies) BAR10 Seies BTR10 Seies Boe Diamete mm D 1 2B 1 d TAC29D Seies TAC20D Seies Boe Diamete mm Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Double-Diection Angula Contact Thust Ball Beaings (TAC Seies) D T C 1 d a Bounday Dimensions Basic Load Ratings Pemissible Effective Load Mass Limiting Speeds ( 2 ) Beaing (mm) (kn) Axial Cente (kg) (min 1 ) Numbes d D 2B 1 C a C 0a Load ( 1 ) (mm) (min.) (min.) (Dynamic) (Static) (kn) a (appox.) Gease Oil 110BAR10S BAR10H BTR10S BTR10H BAR10S BAR10H BTR10S BTR10H BAR10S BAR10H BTR10S BTR10H BAR10S BTR10S BAR10S BTR10S BAR10S BTR10S BAR10S BTR10S BAR10S BTR10S BAR10S BTR10S BAR10S BTR10S Bounday Dimensions Basic Load Ratings Mass Limiting Speeds ( 1 ) Beaing (mm) (kn) (kg) (min 1 ) Numbes d D T C 1 C a C 0a (min.) (min.) (Dynamic) (Static) (appox.) Gease Oil 140TAC20D+L TAC29D+L TAC20D+L TAC29D+L TAC20D+L TAC29D+L TAC20D+L TAC29D+L TAC20D+L TAC29D+L TAC20D+L TAC29D+L TAC20D+L TAC29D+L TAC29D+L TAC29D+L TAC29D+L ( 1 ) Limiting speeds listed on this page ae based on ecommended standad peload (C6 & C7) Note: Beaing type TAC29D: nominal contact angle 60 Beaing type TAC20D: nominal contact angle 60 Angula Contact Thust Ball Beaings ROBUST/Double-Diection ( 1 ) Fo pemissible axial load, please efe to Page 147. ( 2 ) Fo application of limiting speeds, please efe to Page 170. Limiting speeds listed on this page ae based on a back-to-back aangement (DB) with exta light peload (EL). Adjust the limiting speed to 85% of the figue shown when a light peload (L) has been selected. Note: Beaing type BAR10: nominal contact angle 30 Beaing type BTR10: nominal contact angle

55 4. BALL SCREW SUPPORT BEARINGS Pat4 Machine Tool Applications TACB Seies Electic Injection Molding Machines Applications TAC02 and 03 Seies Machine Tool Applications Ball Scew Suppot Units Ball Scew Suppot Beaings Angula Contact Thust Ball Beaings fo Ball Scew Suppot P Featues Numbeing System Beaing Tables Machine Tool Applications TAC B Seies Electic Injection Molding Machine Applications TAC02 and 03 Seies Units fo Ball Scew Suppot P Featues Numbeing System Suppot Units Tables B/S Suppot Ball Scew Sup pot Beaings

56 4. BALL SCREW SUPPORT BEARINGS Angula Contact Thust Ball Beaings fo Ball Scew Suppot Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Featues Numbeing System of Angula Contact Thust Ball Beaings fo Ball Scew Suppot (Machine Tool Applications) High pecision angula contact thust ball beaings to suppot pecision ball scews, have bette pefomance than ealie combinations of angula contact ball beaings o combinations using thust beaings. They ae especially suitable fo high pecision machine-tool feeding mechanisms and simila applications. TAC B Seies (Machine Tool Applications) The axial igidity is high because of a lage numbe of balls and a contact angle of 60. Compaed with tapeed olle beaings of cylindical olle beaings, this type has lowe stating toque; so smoothe otation is possible with less diving foce. (Beaing numbe example) Nominal boe diamete Beaing type symbol Nominal oute diamete Intenal design symbol 30 TAC C 62 B DF C10 PN7A Accuacy symbol Peload symbol Aangement symbol Seal symbol Refeence pages TAC B seies beaings incopoate NSK s ecently developed molded polyamide esin cage. In addition, using exta-pue (EP) steel fo the inne and oute ings has futhe enhanced sevice life. Ou EP steel is manufactued by contolling the amount of hamful oxide inclusions, which eliminates lage size inclusions and enjoys highe puity than vacuum ac emelted (VAR) steel. This seies with DG seal, low toque contact seal, with WPH gease, an watepoof gease, incease the eliability and povide fo easy handling. TAC02 and 03 Seies (Electic Injection Molding Machines) TAC02 and 03 seies ae angula contact ball beaings that povide suppot fo lage size ball scews opeating unde a heavy load fom the diving mechanism of electic injection molding machines. Low toque is achieved by optimum design of the ball beaings. Uses can significantly educe beaing toque by eplacing thei olle beaings with these seies. TAC B and TAC02, 03 Diffeences Electic injection molding machines poduce a heavie load on ball scew suppot beaings than that of machine tools. TAC02 and 03 beaings ae designed to opeate unde such heavy load conditions. Convesely, TAC B beaings ae designed fo inceased pemissible load by inceasing the numbe of balls and beaing width. 30 Nominal boe diamete Boe diamete (mm) TAC Beaing type Angula contact thust ball beaing; 60 contact angle 30, Nominal oute diamete Oute diamete (mm) B Intenal design Seal No symbol: open type DDG: contact ubbe seal ( 1 ) 30 DF C10 Peload C10: standad peload C9: light peload (low toque specification) , 168 PN7A SU: univesal aangement (single ow) DU: univesal aangement (double ow) DB: Back-to-back aangement DF: Face-to-face aangement Aangement DT: tandem aangement DBD, DFD, DTD: tiplex set aangement DBB, DFF, DBT, DFT, DTT: quaduplex set aangement PN7A: standad accuacy (Equivalent to ISO Class 4) Accuacy PN7B: special accuacy (Boe diamete and outside diamete ae exclusive to NSK. Equivalent to ISO Class 4. Fo SU aangement only.) 183 ( 1 ) Sealed angula contact ball beaings fo ball scew suppot ae standadized fo SU aangement and PN7B accuacy. Numbeing System of Angula Contact Thust Ball Beaings fo Ball Scew Suppot (Electic Injection Molding Machines) B/S Suppot Fig. 4.1 (Beaing numbe example) Nominal boe diamete Beaing type symbol Dimension seies symbol Intenal design symbol 30 TAC 02 A T85 SU M PN5D Accuacy symbol Peload symbol Aangement symbol Cage symbol Refeence pages 30 Nominal boe diamete Boe diamete (mm) TAC Beaing type Angula contact thust ball beaing; 60 contact angle 31, Dimension seies 02: 02 seies, 03: 03 seies 108 A Intenal design T85 Cage T85: polyamide esin cage M: machined bass cage SU Aangement SU: univesal aangement (single ow) M Peload M: standad peload , TAC100B (TAC B seies) 55TAC120B (TAC B seies) 55TAC03A (TAC02, 03 seies) PN5D Accuacy PN5D: standad accuacy (Equivalent to ISO Class 5)

57 4. BALL SCREW SUPPORT BEARINGS Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Fo Machine Tool Applications B 1 B 1 TAC B Seies Boe Diamete mm D D 1 d1 d d2 D 2 D D1 d1 1 1 d D2 d2 (Open type) Bounday Dimensions Refeence Dimensions Recommended Limiting Speeds ( 1 ) Beaing (mm) (mm) Gease (min 1 ) Numbes d D B 1 Quantities (min.) (min.) d1 d 2 D 1 D 2 (cc) Gease Oil 15 TAC 47B TAC 47B TAC 47B TAC 62B TAC 62B TAC 72B TAC 72B TAC 90B TAC 75B TAC 100B TAC 100B TAC 100B TAC 120B TAC 120B (Sealed type) Open type Sealed type DDG Bounday Dimensions Refeence Dimensions Limiting Speeds ( 1 ) Beaing (mm) (mm) (min 1 ) Numbes d D B 1 (min.) (min.) d1 d 2 D 1 D 2 Gease 15 TAC 47B DDG TAC 47B DDG TAC 47B DDG TAC 62B DDG TAC 62B DDG TAC 72B DDG TAC 72B DDG TAC 90B DDG TAC 100B DDG Single Row Load DF, DB (kn) Basic Dynamic Load Rating Ca Limiting Axial Load ( 2 ) Double Row Load DT, DFD, DBD, DFF, DBB (kn) Single Row Load DF, DB (kn) Tiple Row Load DTD, DFT, DBT (kn) Single Row Load DF, DB (kn) Double Row Load DT, DFD, DBD, DFF, DBB (kn) Basic Dynamic Load Rating Ca Limiting Axial Load ( 2 ) Double Row Load DT, DFD, DBD, DFF, DBB (kn) Tiple Row Load DTD, DFT, DBT (kn) Single Row Load DF, DB (kn) Double Row Load DT, DFD, DBD, DFF, DBB (kn) Tiple Row Load DTD, DFT, DBT (kn) Tiple Row Load DTD, DFT, DBT (kn) Mass (kg) (appox.) Mass (kg) (appox.) B/S Suppot Fo Machine Tool Applications ( 1 ) Limiting speeds ae based on C10 peload. In case of C9 peload, the figues become 1.3 times of the figues listed above. Also, the figues ae fee of the influence aangement type. Note: Beaing type TAC B: nominal contact angle 60 ( 2 ) Pemissible axial load equals 0.7 times of limiting axial load

58 4. BALL SCREW SUPPORT BEARINGS Fo Electic Injection Molding Machines TAC02 and 03 Seies Boe Diamete mm D 1 D 1 d 1 B 1 d d2 D 2 Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Bounday Dimensions Refeence Dimensions Recommended Contact Beaing (mm) (mm) Gease angle Limiting Speeds Numbes d D B 1 Quantities d1 d 2 D 1 D 2 (Degee) (min 1 ) (min.) (min.) (cc) 15TAC02AT TAC02AT TAC35-2T TAC03AT TAC03AT TAC45-2T TAC03AT TAC03AT TAC03AT TAC03AM TAC03CMC TAC03CMC Single Row Load DF, DB (kn) Dynamic Axial Load Rating Ca Limiting Axial Load ( 1 ) Double Row Load DT, DFD, DBD, DFF, DBB (kn) Tiple Row Load DTD, DFT, DBT (kn) Single Row Load DF, DB (kn) Double Row Load DT, DFD, DBD, DFF, DBB (kn) Tiple Row Load DTD, DFT, DBT (kn) B/S Suppot ( 1 ) Pemissible axial load equals 0.7 times of limiting axial load. Fo Electic Injection Molding Machines

59 4. BALL SCREW SUPPORT BEARINGS Units fo Ball Scew Suppot Numbeing system of suppot units Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 The suppot unit fo heavy-load machine tools employs a high pecision, high igidity Angula contact thust ball beaing fo Ball Scew Suppot (TAC Seies), which is stuctued to function optimally as a suppot beaing fo a ball scew. Thee types of aangements ae available, as descibed in the figue below: Featues The dust-esistant design allows a use to easily design suppot side of ball scew. Since a peload-contolled beaing is incopoated into the suppot unit, the pocess of mounting a beaing can be omitted. Suppot unit numbe example: Suppot unit symbol Nominal beaing boe B 1 A 3 7 WBK C Pat No. ➀ ➁ ➂ ➃ ➄ ➅ ➆ ➇ DFD - 31 Name of Pat Seial numbes Beaing aangement symbol DF: Double ow aangement DFD: Tiple ow aangement DFF: Quaduple ow aangement Components of suppot unit Housing Retaining cove Angula contact thust ball beaings fo Ball Scew Suppot Dust seal Colla Peload secuing bolt Shim Locknut Quantities set o 8 1 set 1 1. Use datum faces A and B to mount the suppot unit to a machine base. 2. Do not ty to disassemble the NSK Suppot Unit because its peload is adjusted with high pecision and the components of numbes ➀, ➁, ➂, ➃, ➅ and ➆ ae integated into a single piece. 3. Gease is packed in the beaing. 4. Locknut ➇ is designed specifically fo ball scews with its pependiculaities contolled against the tiangula thead of the scew. To pevent loosening, tighten the locknut using tunpeventive small scews. The locknut is also available sepaately. Fo Angula contact thust ball beaings fo Ball Scew Suppot, please efe to Page 110. L L P Tap depth Q (both sides) 4-P Tap depth Q (both sides) Dg6 d1 H8 d d1 H8 D2 D1 D3 M d M V W V W DF aangement WBK DF-31 DFD aangement WBK DFD-31 DFF aangement WBK DFF-31 l L1 L L2 l L3 Locknut L4 L5 Dimensions of unit mounting face 6- X Dill thu Y C'boe, Z deep A 8- X Dill thu Y C'boe, Z deep Intenal boe d 30 Intenal boe d 35 A B/S Suppot Remaks: Suppot Unit Numbes WBK17DF-31 WBK20DF-31 WBK25DF-31 WBK25DFD-31 WBK30DF-31 WBK30DFD-31 WBK35DF-31 WBK35DFD-31 WBK35DFF-31 WBK40DF-31 WBK40DFD-31 WBK40DFF-31 Suppot Unit Pats d D D 1 D 2 L L 1 L 2 A W X Y Z d 1 * l * V * P * Q * M M M M M M Rigidity: Rigidity values in the table show theoetical values calculated fom elastic displacement between gooves and steel balls. 2. Stating toque: Stating toque in the table shows stating toque necessay fo a peloaded beaing, not including seal toque. 3. Toleance of Shaft Oute Diamete at the beaing seat fo unit: h5 Class is ecommended fo the Shaft Oute Diamete at the beaing seat fo unit. Basic dynamic load ating C a (N) Limiting Axial Load (N) Peload (N) Axial Rigidity (N/µm) Stating toque (N cm) Locknut Unit: mm Beaing seat fo unit M D 3 L 3 d L 4 L 5 M17 1 M20 1 M M M M Remaks: 4. Dimensions maked with * The spigot and scew pats maked with * ae used fo mounting a seal unit fo the NSK standad hollow ball scew shaft as well as fo mounting a dust cove and dampe. 5. Because gease is packed in the beaing, it can be used immediately as is. Units fo Ball Scew Suppot

60 5. PRECISION DEEP GROOVE BALL BEARINGS Pat4 Pecision Deep Goove Ball Beaings Polyamide Resin Cage Pecision Deep Goove Ball Beaings Pecision Deep Goove Ball Beaings P Featues Numbeing System Beaing Tables T1X Type (Polyamide esin cage) 60, 62 and 63 Seies Pecision Deep Goove Ball Beaings Pecision Deep Go ove Ball Beaings

61 5. PRECISION DEEP GROOVE BALL BEARINGS Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Featues Capable of beaing not only adial loads but also axial loads in both diections. Fictional toque is small, thus suitable fo opeations equiing high speed, low noise, and low vibations. Thee types ae available: open type; shielded type (steel shield); and sealed type (ubbe seal). Dimension seies Numbeing System of Pecision Deep Goove Ball Beaings (Beaing numbe example) Beaing type symbol Dimension symbol Boe numbe Mateial symbol T1X ZZ C3 P4 Accuacy symbol Radial cleaance symbol Seal and shield symbol Cage symbol Refeence pages 6 Beaing type 6: single-ow deep goove ball beaing Dimension 0: 10 seies, 2:02 seies, 3: 03 seies Boe numbe Less than 03 beaing boe 00: 10 mm, 01: 12 mm, 02: 15 mm, 03: 17 mm Moe than 04 beaing boe: Boe numbe x 5 (mm) 120 Mateial No symbol: beaing steel (SUJ2) SN24: ceamic ball (Si 3 N 4 ) T1X Cage T1X: ball guided polyamide esin cage TYA: high speed, ball guided polyamide esin cage 118 Stuctue ZZ Seal and shield No symbol: open type ZZ: steel shield VV: non-contact ubbe seal 118 Open type Shielded type (ZZ) Non-contact ubbe seal type (VV) C3 Radial No symbol: nomal cleaance C3: lage than nomal cleaance CM: special cleaance fo electic moto cleaance CG: special adial cleaance P4 Accuacy P2: ISO Class 2 P4: ISO Class 4 P5: ISO Class Pecision Deep Goove Ball Beaings Cages T1X Ball guided polyamide esin cage: povides supeio wea esistance fo geneal pupose motos. TYA Ball guided polyamide esin cage: incopoates the same design concepts of angula contact ball beaings fo high-speed motos. T Inne ing guided phenolic esin cage: well balanced symmety, offeing supeio heat esistance fo high speed opeations of woodwoking machiney spindles

62 5. PRECISION DEEP GROOVE BALL BEARINGS T1X Type (Polyamide Resin Cage) 60, 62 and 63 Seies Boe Diamete mm Open type Shield type Seal type 6000 ZZ VV d B D Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Bounday Dimensions Basic Load Ratings Beaing( 1 ) (mm) (kn) Limiting Speeds ( 2 ) Numbes Shield type Seal type C d D B C 0 (min 1 ) (Dynamic) (Static) 6000T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV T1X ZZ VV Pecision Deep Goove Ball Beaings ( 1 ) TYA cage available fo high-speed moto application. Contact NSK fo details. ( 2 ) Limiting speed figues ae based on T1X. Adjust the limiting speeds by 115% fo TYA cages

63 6. PERIPHERAL EQUIPMENT Pat4 Peipheal Equipment Gauges P GR Gauges Featues Numbeing System GTR Gauges Featues Numbeing System GN Gauges Featues Numbeing System Beaing Monito P128 Beaing Heate P129 Gease Replenishing System P Oil-Ai Lubicato P Sealed Pecision Spaces fo Machine Tool Spindles P Peipheal Equipment Peipheal Equ ipment

64 6. PERIPHERAL EQUIPMENT Ring Gauges GR Seies Housing boe diamete pecision measuing gauges d B To obtain satisfactoy pefomance of pecision olling beaings fo machine tool spindles, it is impotant to have an accuate fitting with the shaft and housing. To achieve an accuate fitting, it is necessay to measue the shaft outside diamete and housing boe exactly. NSK Ring Gauges GR seies ae maste gauges fo measuing the boe diametes of housings within an accuacy of mm. Featues Ring design enables eliable cylinde gauge settings. Ring thickness eliminates any defomation caused by measuing pessue. Heat teatment duing manufactuing of the ing negates any effects of aging on ing dimensions. Exact gauging is possible due to pecisely measued dimensions that ae maked on the gauges in mm units in both the X and Y diections. Tape Gauges GTR30 Seies Shaft tape measuing gauges Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 NN30XXKR ae tapeed boe, double ow cylindical olle beaings that have high igidity and ae suitable fo high speeds, so they ae often used in machine tool spindles. To use these beaings, it is impotant to exactly match the tape of the beaing boe with that of the spindle. The beaing tape (tape 1:12) is pecisely contolled and manufactued fo a specific accuacy. A Tapeed Gauge GTR30 is one whose boe is pecision finished with a tape identical with that of a beaing. By machining the tape of a spindle to match this tape gauge, its exact contact with the beaing is assued. Featues Ring thickness eliminates any defomation caused by measuing pessue. Heat teatment duing manufactuing of the ing negates any effects of aging on ing dimensions. 124 D Applicable Beaings Bounday Dimensions (mm) Mass 69 BNR19 60 BNR10 72 Gauge (kg) NN39 BER19 N10 BER10 62 Numbes d D B NN49 NN30 N2 (appox.) 00 GR GR GR GR GR GR GR GR GR GR GR GR GR GR GR GR GR GR GR GR GR GR GR GR GR GR GR GR GR GR GR GR GR GR GR Type I Tape 1:12 D d1 d2 B 2-g Type II Tape 1:12 Bounday dimensions Mass Applicable Gauge (mm) (kg) Types Beaings Numbes d 1 d 2 D B L g (appox.) NN3006KR GTR M NN3007KR GTR M NN3008KR GTR M NN3009KR GTR M NN3010KR GTR M NN3011KR GTR M NN3012KR GTR M NN3013KR GTR M NN3014KR GTR M NN3015KR GTR M NN3016KR GTR M NN3017KR GTR M NN3018KR GTR NN3019KR GTR NN3020KR GTR NN3021KR GTR NN3022KR GTR NN3024KR GTR NN3026KR GTR NN3028KR GTR NN3030KR GTR NN3032KR GTR d d1 d2 L B Peipheal Equipment 125

65 6. PERIPHERAL EQUIPMENT GN gauges GN30 Seies Pecision measuing gauges fo esidual adial cleaance of double-ow cylindical olle beaings (NN30XX) Type I Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Type II D D L L B B When mounting a double-ow cylindical olle beaing with a tapeed boe onto a shaft, it is impotant to accuately match the spindle tape with that of the beaing, and to ensue that the desied adial intenal cleaance is attained afte mounting. If thee is excessive esidual adial intenal cleaance, the main shaft will have some play and machining accuacy will be advesely affected. If cleaance is too small, despite little o no change in igidity, heat geneation will become excessive and olling fatigue life will be extemely shotened (See page 155). With the ecent tends towad highe speed and highe pecision, it is necessay to contol esidual adial intenal cleaance moe caefully. In the past, adial cleaance measuing methods wee vey difficult and equied much skill. GN gauges developed by NSK fo esidual adial intenal cleaance measuements of double-ow cylindical olle beaing simplify beaing mounting and impove mounting accuacy. (Use of GN gauges also equie a boe measuing cylinde gauge.) Featues Simple, eliable, and accuate measuements can be made. No moe complicated calculations fo coections based on intefeence of an oute ing with housing. Both positive and negative cleaance (peload) can be measued. Accuate measuements ae obtained since all GN gauges ae calibated fo measuing pessue. Bounday dimensions Mass Applicable Gauge (mm) (kg) Beaings Numbes Types D B L (appox.) NN3007 GN NN3008 GN NN3009 GN NN3010 GN NN3011 GN NN3012 GN NN3013 GN NN3014 GN NN3015 GN NN3016 GN NN3017 GN NN3018 GN NN3019 GN NN3020 GN NN3021 GN NN3022 GN NN3024 GN NN3026 GN NN3028 GN NN3030 GN NN3032 GN Peipheal Equipment

66 6. PERIPHERAL EQUIPMENT Beaing Monito NB-4 Beaing Heate Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Waning light LED flashes if isolated beaing flaws exist. Function Switch To select displacement, velocity, o acceleation. Mode Switch To select ms o peak eadings and output signals. Sensitivity Switch To select high o low sensitivity o tun powe off. NB-4 Main Body Helical Cable A tangle-fee, extendable cable may be used to connect the vibation pick-up, o it can be connected diectly to the main body. Optional fixed pick-up Held by magnet o scew (watepoof) Micoelectonics allow the NB-4 Beaing Monito (a vibation monito) to be a conveniently potable size. With high sensitivity and a vaiety of functions built in, it can quickly and eliably detect unusual vibations in beaings o machines, and wan of possible touble. Featues Vibations can be measued and ecoded and then displayed as a wavefom (ecoded by a pesonal compute o othe device). The envelope function of the NB-4 makes it possible to detect any damage on the aceway of a beaing. Liquid Cystal Display Vibation data ae shown. Low battey voltage, excessive input, and PEAK mode selection ae also indicated. Hold Button Displayed vibation data (LCD) is held constant. Eaphone Output Vibational sound may be head using eaphones and the volume contolle. Output Teminal Displays eithe a vibation wavefom o a wavefom envelope signal. Helical Cable connected to hand-held pobe Pobe Type Pick-up Hand-held Vibation Pick-up Supeio high-fequency esponse allows ealy detection of touble in beaing and othe machine pats. NB-4 Main Body connected to handheld Vibation Pick-up Dimension Infomation 297 mm 0110/ mm 175 mm 573 mm 347 mm Type/Capacity KVA KVA Powe voltage 100 V 1ø Common fo 50/60 Hz 200 V 1ø Common fo 50/60 Hz Applicable beaing sizes Max200 mm Max. 80 mm Min. 20 mm A beaing heate heats a beaing evenly and quickly to fit the beaing on a spindle, thus enabling clean mounting without oil. A beaing heate can be used to heat not only beaings but also ing-shaped metal pats, such as geas. Featues Rapid and even heating No heating oil is equied, thus thee is no geasy dit. Suitable fo shinkage fit of beaings as well as ingshaped metal pats. Use-fiendly opeation panel In conjunction with an ulta-compact high sensitive tempeatue senso, the heate indicates pecise, eal-time tempeatues though digital display, iespective of heating speed o detection aea. The heate stats o stops at the flick of a button. The time can be set fo a maximum of 100 minutes. *Extenal input/output teminals fo emote contol on-line ae featued as standad, enabling factoy automation as well. A supeio level of safety The heate automatically stops pomptly if heat is applied without setting the tempeatue senso o in the event of a device failue. Compatible with vaious sizes of boes By selecting an I-type coe that matches the boe of a beaing, one beaing heate can be compatible with beaings of vaious sizes. Automatic heating unde optimal conditions Electical popeties change depending on the type of beaing and I-type coe used. The heate automatically detects these changes and thus always applies heat optimally. Also, as the output is adjustable fom 50% to 100% in incements of 10%, the heate is ideal fo delicate beaings that equie gadual heating. Max. 70 mm MAX12 kg Heating pefomance cuve (example) Inne ing tempeatue incease, C Deep Goove Ball Beaings I-type coe 15 mm I-type coe 25 mm I-type coe 35 mm Heating peiod, min Peipheal Equipment

67 6. PERIPHERAL EQUIPMENT Gease Replenishing System FINE-LUB II Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Until ecently, high-speed spindles have used oil-ai o oil-mist lubication. Cuent woldwide concen fo the envionment equies a new system that educes noise and oil mist while suppoting clean woking envionment and enegy saving. In esponse to this demand, NSK has developed FINE-LUB II, the wold s fist gease-eplenishing system fo high-speed machine tool spindles. Dimensions 94 Gease outlet (M8 1) Ai connection pot 2 (Rc1/8) 102 Level switch (to monito emaining gease amount) (136) Ai connection pot 1 (Rc1/8) Refilling plug of gease Pessue switch 50 FINE-LUB II feeds a small amount of gease into high-speed beaings at egula intevals and dischages old gease, though an optimally shaped space, to a gease stoage located in the housing. This technology delives the wold s fist gease lubication system fo the high-speed spindles of machine tools and, at the same time, inceases the opeating lifetime. This evolutionay poduct completely tansfoms the concept of gease lubication. FINE-LUB II leads the way to a new type of gease lubication, making it faste, accuate, and moe comfotable. Model Numbe 6.5 Insciption numbe (Installation hole) Specifications Gease outlet Featues Longe opeating life fo lubicating gease The opeating lifetime of gease is seveal hunded hous duing continuous otation at a speed of 1.8M d m n (#40 tape min 1 ). FINE-LUB II has been developed with the aim of feeding in an appopiate amount of gease depending upon the otation speed and beaing size to avoid seizue, theeby ensuing moe than hous of maintenance-fee pefomance. Contolling the dischage of lubicating gease to pevent tempeatue incease. Feeding too much gease into the inside of a beaing can cause the tempeatue to incease due to gease chuning. To pevent this, FINE-LUB II featues a built-in device to ensue that an appopiate amount of gease is dischaged. EGU - 2P1-4P2 Two of P1 pots Fou of P2 pots EGU - 6P1 Six of P1 pots Dischage amount (cc/cycle) Code numbe P1 P2 Item Ai feeding pessue Dischage amount Tank capacity Monitoing function Pipe length Gease type Specification 0.25 to 0.4 MPa 0.01 o 0.02/beaing in a ow 200 cc Detection of emaining gease amount, detection of pessue (check of pessue incease) 2.5 m o less MTE gease System Diagam The Mechanism fo Feeding Gease to Beaings Coss-section of spindle Stoage goove fo dischaging old gease Replenished gease Housing Space fo dischaging gease Beaing shape designed specifically fo gease eplenishing Gease eplenishing method A small amount of gease is fed into a otating beaing at egula intevals though a gease inlet located nea the oute ing aceway. The gease is fed in small amounts to pevent the beaing tempeatue fom inceasing. Gease eplenishing device Gease 200 cm 3 Gease level switch Pessue switch Spindle Ai fo diving piston Ai fo pessuing tank Rotational speed signal Gease eplenishment Signal to eplenish Pessue switch Spindle Amplifie Replenishing inteval calculation Peipheal Equipment 130 High-speed angula contact ball beaings Gease dischaging method A specially shaped space fo gease dischage, located at the counte-boe side of the beaing, diects old gease into a stoage goove, peventing it fom e-enteing the inside of the beaing. Solenoid valve Ai supply souce NC contolle 131

68 HPS LPS APS FS min./imp. CK LA MA AS R IGZ38-F PERIPHERAL EQUIPMENT FINE-LUB Oil-Ai Lubicato Featues Remakable technological innovations continue in the field of machine tools. Paticulaly, spindle motos ae opeating faste than befoe. New developments fo impoving beaing and lubication methods to facilitate the highe speeds ae theefoe vital. NSK has made many developments in oil-ai lubication systems and oil supply equipment. In 1984, NSK intoduced the FINE-LUB oil-ai lubicato to the maket, and continues to enjoy success with this poduct. The FINE-LUB has evolved with the times, and has been adopted fo use in many machine tools, while eaning a eputation fo excellent pefomance and high eliability. The FINE-LUB oil-ai lubicato has a leading position in the oilai lubication maket. This unit povides oil-ai lubication by a system, which consists of a pump, mixing valves, and a contol unit. Reliability has been futhe impoved by incopoating safety devices. OAEM Pump Unit 380 (12) Featues Ai pessue gauge Ai connection pot (RC1/4) Wie connection pot (G1/2) Ai pessue switch Level switch Oil tank Contolle Oil pessue switch MK MK Suction 221 Gea diven pump Oil supply pot Filte The OAEM unit is a newly developed low viscosity gea diven pump. (Opeating oil viscosity ange: mm 2 /s) A special contolle is used to set lubicating intevals at 1, 2, 4, 8, 16, 24, 32, 48, 64, o 128 minutes. Standad safety devices include: ➀Oil level switch ➁Powe failue waning ➂Ai pessue switch ➃Oil pessue switch Mounting hole: (181) Tank (Level switch) Compessed ai Contolle Pessue switch Pump Filte Pessue switch Pessue gauge Quantity contol piston Pump unit Nozzle 1.0 Mixing valve [Pecautions] Use clean, dy compessed ai at a pessue of MPa. Use fesh, clean lubicating oil with a viscosity of ISO VG 10 o highe. Please take exta cae to avoid oil contamination, which can shoten the life of equipment. Take exta cae in selecting quality oil lines fo use between the pump and mixing valves. Oil lines exceeding 5 m in length equie you contact NSK pio to use. Oil lines fom the mixing valve to the spindle should be limited to m. Model numbe: OAEM (Incl. contolle) OAEM-N (No contolle) Lubication: high speed spindle oil, o tubine oil Powe supply: 100 V Tank capacity: 2.7 L Effective oil level: 1.7 L Components of pump unit: Contolle, ai pessue switch, Oil pessue switch and Float switch. NSK also offes a moe economical pump unit that is CE Mak appoved. This pump can be contolled exclusively by ou contolle, o by a machine equipment sequence. Mixing Valve MVF Oil connection pot Oil connection pot M10 1, fo 6 tubing 67 (Dimension including ai bleed valve) Meteing nipple Stamped numbe Ai bleed button ( 1 ) o Ai bleed plug Featues Ai flow contol scew Ai connection pot M12 1 Ai bleed button ( 2 ) Oil-ai outlet M8 1, 4 tube Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 8 A 3 B P (Dawing is fo MVF5) L Oil ai Adopts a piston-type contol fo dischaging small, fixed quantities of oil. Dischaged quantities of 0.01, 0.03, and 0.06 cm 3 pe stoke can be selected. Numbe of outlets and dischage quantities can be selected depending on each condition. Notes ( 1 ) In case the dischaged quantity is 0.01 cm 3, use Ai bleed plug fo Ai bleed pocedue. In case the dischaged quantity is 0.03 cm 3, o 0.06 cm 3, attach Ai bleed button instead of Ai bleed plug, fo Ai bleed pocedue. ( 2 ) In case the dischaged quantity is 0.03 cm 3, o 0.06 cm 3, attach the Ai bleed button to this position, duing the opeation. Optional Pats [Pessue switch] OAG Monitos fo inceases in ai and oil pessue and dop in oil pessue. (Equipped on OAEM) [Oil-Ai Senso] The oil-ai senso makes it possible to impove the eliability of oil-ai lubication by monitoing oil paticles supplied fom a mixing valve to a beaing. The device can be added late to an existing oil-ai system by connecting the device to an oil-ai pipe. B Ai Oil holes Type numbe Numbe of valves L A P B MVF MVF MVF MVF MVF MVF Dischage quantity (cm 3 /stoke) Stamping numbe Code numbe P P P3 [Oil Filte] OAV-02/03 Filtes emove minute foeign paticles fom the oil. Two types ae available: 3 µm and 20 µm [Ai Bleed Valve] OAV-01 Bleed valves facilitate bleeding ai afte disconnecting oil lines fo maintenance of the lubicato. Peipheal Equipment 133

69 6. PERIPHERAL EQUIPMENT Sealed Pecision Spaces fo Machine Tool Spindles Pat 1 Pat 2 Pat 3 Pat4 Pat 5 Pat 6 Pat 7 Pat 8 Featues Specification In the past, labyinth spaces wee used to pevent foeign matte fom enteing a beaing in a spindle. Howeve, because Mateial fo outeing space SUJ2 the cleaance between inne and oute space ings is lage, the enty of foeign matte cannot be completely pevented. NSK Mateial fo inneing space SUJ2 succeeded in naowing the gap between them by attaching seals to spaces. The double stuctue of a labyinth space plus a seal impoves the eliability of the spaces. Envionmentally-sound Attached seals pevent the leakage of gease Enhanced eliability Fo gease lubication, a double-laye stuctue of a labyinth space plus a seal povides supeio esistance against enty 3 Seal B Oil outlet 3 (two place) Oute-ing space Inne-ing space Seal mateial Nitile ubbe, SECC Handling pecautions Note that an inne-ing space and an oute-ing space can be sepaated, so take cae that ubbe seal do not fall out o sustain damage duing handling. Use univesal combination beaings (see pages ) with sealed pecision spaces. Configuation example Labyinth stuctue Sealed space of dust and coolant. The example in the figue on the left contains a tiple-seal configuation the labyinth seal which consists of the etaining D (g5) De1 D i1 d (F7) cove and the inne-ing space povide the fist seal, followed by the sealed pecision space with an additional built-in Numbeing system labyinth seal. Numbe example: X 65 - MTV 10 Dimensions Space symbol 10: 10 Seies 19: 19 Seies Nominal Boe diamete Type symbol Oil outlet Dimensions (19 Seies) Dimensions (10 Seies) 134 Refeence numbe X30-MTV19 X35-MTV19 X40-MTV19 X45-MTV19 X50-MTV19 X55-MTV19 X60-MTV19 X65-MTV19 X70-MTV19 X75-MTV19 X80-MTV19 X85-MTV19 X90-MTV19 X95-MTV19 X100-MTV19 X105-MTV19 X110-MTV19 Boe diamete d (mm) Oute diamete D (mm) Width B (mm) D i1 (mm) D e1 (mm) Space chambe (mm) Refeence numbe X30-MTV10 X35-MTV10 X40-MTV10 X45-MTV10 X50-MTV10 X55-MTV10 X60-MTV10 X65-MTV10 X70-MTV10 X75-MTV10 X80-MTV10 X85-MTV10 X90-MTV10 X95-MTV10 X100-MTV10 X105-MTV10 X110-MTV10 X120-MTV10 Boe diamete d (mm) Oute diamete D (mm) Width B (mm) D i1 (mm) D e1 (mm) Space chambe (mm) Peipheal Equipment 135

70 TECHNICAL GUIDE Pat5 Technical Guide 1. Life P Rolling Fatigue Life and Basic Load Rating New Life Theoy 2. Static Load Ratings and Static Equivalent Loads P Angula Contact Ball Beaing Combinations P Featues of Each Combination Univesal Combination 4. Peload and Rigidity P Types of Peload and Rigidity Peload and Rigidity Tables 5. Limiting Speeds P Lubication P Beaing Toleances P Toleance fo Radial Beaings Toleances fo Tapeed Boes Toleances fo Angula Contact Thust Ball Beaings 8. Designing of Shafts and Housings P Fitting of Shafts and Housings Shafts and Housing Toleance Shoulde and Fillet Dimensions Chamfe Dimensions 9. Spaces P Space Dimensions Position of Spay Nozzle Life Static Load Ratings and Static Equivalent Loads Angula Contact Ball Beaing Combinations Design of Shafts and Housings Peload and Rigidity Limiting Speeds Lubication Beaing Toleances Technical Gui de 136 Spaces 137

71 1. LIFE Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Rolling Fatigue Life and Basic Load Rating Beaing Life The vaious functions equied of olling beaings vay accoding to the beaing application. These functions must be pefomed fo a polonged peiod. Even if beaings ae popely mounted and coectly opeated, they will eventually fail to pefom satisfactoily due to an incease in noise and vibation, loss of unning accuacy, deteioation of gease, o fatigue flaking of the olling sufaces. Beaing life, in the boad sense of the tem, is the peiod duing which beaings continue to opeate and to satisfy thei equied functions. This beaing life may be defined as noise life, abasion life, gease life, o olling fatigue life, depending on which one causes loss of beaing sevice. Aside fom the failue of beaings to function due to natual deteioation, beaings may fail when conditions such as heatseizue, factue, scoing of the ings, wea of the seals, o othe damage occus. Conditions such as these should not be intepeted as nomal beaing failue since they often occu as a esult of eos in beaing selection, impope design o manufactue of the beaing suoundings, incoect mounting, o insufficient maintenance. inopeable due to flaking. In detemining beaing life, basic ating life is often the only facto consideed. Howeve, othe factos must also be taken into account. Fo example, the gease life of geasepelubicated beaings can be estimated. Since noise life and abasion life ae detemined accoding to individual standads fo diffeent applications, specific values fo noise o abasion life must be detemined empiically. Basic Dynamic Load Rating The basic dynamic load ating is defined as the constant load applied on beaings with stationay oute ings that the inne ings can endue fo a ating life of one million evolutions (10 6 ev). The basic load ating of adial beaings is defined as a cental adial load of constant diection and magnitude, while the basic load ating of thust beaings is defined as an axial load of constant magnitude in the same deflection as the cental axis. The load atings ae listed unde C fo adial beaings and C a fo thust beaings in the dimension tables. Basic Rating Life The following elation exists between beaing load and basic ating life: Dynamic Equivalent Load In some cases, the loads applied on beaings ae puely adial o axial loads; howeve, in most cases, the loads ae a combination of both. In addition, such loads usually fluctuate in both magnitude and diection. In such cases, the loads actually applied on beaings cannot be used fo beaings life calculations; theefoe, a hypothetical load should be estimated that has a constant magnitude and passes though the cente of the beaing, and will give the same beaing life that the beaing would attain unde actual conditions of load and otation. Such a hypothetical load is called the dynamic equivalent load. Assuming the equivalent adial load as P, the adial load as F, the axial load as F a, and the contact angle as α, the elationship between the equivalent adial load and beaing load can be appoximated as follows: P = XF + YF a whee X : Radial load facto Y : Axial load facto See Table 1.1 The axial load facto vaies depending on the contact angle. In the case of olle beaings, the contact angle emains the same } Table 1.1 Value of Factos X and Y Nomal Single, DT DB o DF if o F Contact a e F C a / F e F a / F >e F a /F e F a / F >e 0 Angle X Y X Y X Y X Y Fo i, use 2 fo DB, DF and 1 fo DT Table 1.2 Basic Load Rating of ACBB as Multiple Sets Double Row Tiple Row Quaduple Row C C o C C o C C o 1.62 times elative to Single ow 2 times elative to Single ow 2.15 times elative to Single ow 3 times elative to Single ow 2.64 times elative to Single ow 4 times elative to Single ow Life Rolling Fatigue Life and Basic Rating Life When olling beaings ae opeated unde load, the aceways of thei inne and oute ings and olling elements ae subjected to epeated cyclic stess. Because of metal fatigue of the olling contact sufaces of the aceways and olling elements, scaly paticles may sepaate fom the beaing mateial. This phenomenon is called flaking. Rolling fatigue life is epesented by the total numbe of evolutions at which time the beaing suface will stat flaking due to stess. This is called fatigue life. Even fo seemingly identical beaings, which ae of the same type, size, and mateial and eceive the same heat teatment and othe pocessing, the olling fatigue life vaies geatly, even unde identical opeating conditions. This is because the flaking of mateials due to fatigue is subject to many othe vaiables. Consequently, basic ating life, in which olling fatigue life is teated as a statistical phenomenon, Fo ball beaings Fo olle beaings whee L 10 : Basic ating life (10 6 ev, o h) P C L10= ( L10= ( L10= ( L10= ( ) 3 C P n ) 10/3 C P n ) C P ) C P : Beaing load (equivalent load) (N) (Refe to Page 125) : Beaing dynamic load ating (N) 3 10/3 (h) (h) Fo adial beaings, C is witten C egadless of the magnitude of the axial load. In the case of single ow deep goove ball beaings and angula contact ball beaings, the contact angle inceases when the axial load is inceased. Such change in the contact angle can be expessed by the atio of the basic static load ating C 0 and axial load F a. Table 1.1 shows the axial load facto at the contact angle coesponding to this atio. Regading angula contact ball beaings, the effect of change in the contact angle on the load facto may be ignoed unde nomal conditions even if the contact angle is as lage as 25, 30 o 40. Fo the thust beaing with the contact angle of α 90 eceiving both adial and axial loads simultaneously, the equivalent axial load P a becomes as follows: P a = XF + YF a is used in pefeence to actual olling fatigue life. Suppose a numbe of beaings of the same type ae opeated Fo thust beaings, C is witten C a n : Rotational Speed (min 1 ) individually unde the same conditions. Afte a cetain peiod of time, 10% of them fail as a esult of flaking caused by olling fatigue. The total numbe of evolutions at this point is defined In the case of beaings that un at a constant speed, it is convenient to expess the fatigue life in tems of hous. as the basic ating life o, if the speed is constant, the basic ating life is often expessed by the total numbe of opeating hous completed when 10% of the beaings become

72 1. LIFE Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Life Calculation of Multiple Beaings as a Goup When multiple olling beaings ae used in one machine, the fatigue life of individual beaings can be detemined if the load acting on individual beaings is known. Geneally, howeve, the machine becomes inopeative if a beaing in any pat fails. It may theefoe be necessay in cetain cases to know the fatigue life of a goup of beaings used in one machine. 3 The fatigue life of the beaings vaies geatly and ou fatigue life calculation equation L 10 = ( C ) applies to the 90% life (also called P the ating fatigue life, which is eithe the goss numbe of evolution o hous to which 90% of multiple simila beaings opeated unde simila conditions can each). In othe wods, the calculated fatigue life fo one beaing has a pobability of 90%. Since the enduance pobability of a goup of multiple beaings fo a cetain peiod is a poduct of the enduance pobability of individual beaings fo the same peiod, the ating fatigue life of a goup of multiple beaings is not detemined solely fom the shotest ating fatigue life among the individual beaings. In fact, the goup life is much shote than the life of the beaing with the shotest fatigue life. Assuming the ating fatigue life of individual beaings as L 1, L 2, L 3...L n and the ating fatigue life of the entie goup of beaings as L, the below equation is obtained : whee, e = 1.1 (both fo ball and olle beaings) Life Calculations of Peloaded Angula Contact Ball Beaings To establish the total adial (F ) and axial (F a ) load components on each beaing in a multiple aangement of peloaded angula contact ball beaings, the extenally applied adial load (F e ) and axial load (F ae ), the axial peload (F ao ) and the load distibution must be taken into account. The latte is a function of the olling element to aceway deflection which is popotional to (load) 2/3. The calculation pocedue fo popula mounting vaiations of identical beaings is detailed below. Back-to-back, Pai of Beaings Fao Fae Unde extenal adial load (F e ), total Peload (F ap ) is the following: Fap = when F ap < F ao, use F ap = F ao Total axial component of (F a1, F a2 ) with applied axial load on each beaing (1 and 2): (1) (2) Fe F e 1.2 tanα + F ao 2 F a1 = 2/3F ae + F ap 1 L e = L 1 e Fao L 2 e L 3 e when F a2 < 0 the peload is elieved so that F a1 = F ao, and F a2 = 0 L n e Total adial component of load (F ) on each beaing is popotioned by the atio of the axial load on each beaing to the total axial load, each component aised to the powe of 2/3: F 1 = F 2 = The dynamic equivalent adial load (P 1 ) and (P 2 ) fo each beaing is calculated fom: P 1 = XF 1 + YF a1 P 2 = XF 2 + YF a2 The values of X and Y ae obtained fom Table 1.1 (Page 139) The basic ating life (L 10 ) of each beaing is: The two beaings may be consideed as a unit and accoding to the theoy of pobability, the life of the unit, o pai of beaings, will be shote than the shotest ating life of the individual beaings. Thus: L 10 = 2/3 F a1 Fa1 2/3 2/3 + F a2 2/3 F a2 Fa1 2/3 2/3 + F a2 1 F e F e C L 10 (1) = ( ) 3 n C L 10 (2) = ( ) 3 n P 1 P ( + L1.1 L1.1 ) 10(1) 10(2) (h) (h) (h) DBD Set of Beaings Fao Unde extenal adial load (F e ), total Peload (F ap ) is the following: when F ap1 < F ao /2, use F ap1 = F ao /2 and F ap2 < F ao, use F ap2 = F ao Total axial component of load (F a1, F a2 ) on each beaing with applied axial load : F a1 = 0.4F ae + F ap1 F a2 = F ap2 0.2F ae When F a2 < 0 the peload is elieved so that Total adial component of load (F ) on each beaing : The dynamic equivalent adial load (P 1 ) and (P 2 ) fo each beaing : Fae (1) F ap1 = F ap2 = (1) (2) P 1 = XF 1 + YF a1 P 2 = XF 2 + YF a2 The values of X and Y ae obtained fom Table 1.1, page 139. The basic ating life (L 10 ) of each beaing : Fe F e 1.2 tanα + F ao 4 F e 1.2 tanα + F ao 2 F F a1 = ae and F a2 = 0 2 F 1 = F 2 = L 10 fo the unit = 2/3 F a1 2Fa1 2/3 2/3 + F a2 2/3 F a2 2Fa1 2/3 2/3 + F a2 F e F e C L 10(1) = ( ) 3 n C L 10(2) = ( ) 3 n P 1 P ( + L1.1 L1.1 ) 10(1) Fao (h) (h) 10(2) (h) DBB Set of Beaings Fao Fae Unde extenal adial load (F e ), total Peload (F ap ) is the following: When F ap < F ao /2, use F ap = F ao /2 Total axial component of load (F a1, F a2 ) on each beaing with applied axial load F a1 = 1/3F ae + F ap F a2 = Fap 1/6F ae When F a2 < 0 the peload is elieved so that Total adial component of load (F ) on each beaing : The dynamic equivalent adial load (P 1 ) and (P 2 ) fo each beaing : (1) (1) (2) (2) F ap = P 1 = XF 1 + YF a1 P 2 = XF 2 + YF a2 The values of X and Y ae obtained fom Table 1.1, page 139. The basic ating life (L 10 ) of each beaing : Fe F e 1.2 tanα + F ao 4 F F a1 = ae and F a2 =0 2 F1 = Fa1 2/3 2/3 + F a2 F2 = L 10 fo the unit = 2/3 F a1 2/3 F a2 Fa1 2/3 2/3 + F a2 1 F e 2 F e C L 10(1) = ( ) 3 n C L 10(2) = ( ) 3 n 1 1 ( + L1.1 L1.1 ) 10(1) P 1 P 2 10(2) (h) (h) (h) Fao Life 140 F a2 = F ap 1/3F ae 141

73 1. LIFE New Life Theoy Intoduction Beaing technology has advanced apidly in ecent yeas, paticulaly in the aeas of dimensional accuacy and mateial cleanliness. As a esult, beaings can now have a longe olling fatigue life in a cleane envionment, than the life obtained by the taditional ISO life calculation fomula. This extended life is patly due to the impotant advancements in beaing elated technology such as lubication cleanliness and filtation. The conventional life calculation fomula, based on the theoies of G. Lundbeg and A. Palmgen (L-P theoy, heeafte) addesses only sub-suface oiginated flaking. This is the phenomenon in which cacks initially occu due to dynamic shea stess immediately below the olling suface then pogessively each the suface in the fom of flaking. 1 1n τ o c N e V h S Z o NSK s new life calculation fomula theoizes that olling fatigue life is the sum total of the combined effects of both subsuface oiginated flaking and suface oiginated flaking occuing simultaneously. NSK New Life Calculation Fomula (1) Sub-suface oiginated flaking A pe-condition of sub-suface oiginated flaking of olling beaings is contact of the olling elements with the aceway via a sufficient and continuous oil film unde clean lubication conditions. Fig. 1.1 plots the L 10 life fo each test condition with maximum suface contact pessue (P max ) and the numbe of epeated stesses applied on the odinate and the abscissa, espectively. In the figue, line L 10 theoetical is the theoetical line obtained using the conventional life calculation fomula. As maximum suface contact pessue deceases, the actual life line sepaates fom the line ceated by using conventional theoetical calculation and moves towads longe life. This sepaation suggests the pesence of fatigue load limit P u below which no olling fatigue occus. This is bette illustated in Fig Fig. 1.1 Life Test Result unde Clean Lubication Condition Max suface contact pessue, MPa Beaing load, P P u Flat washe 6204, 10 µm filtated 6206, 10 µm filtated 6206, 3 µm filtated 6206, 10 µm filtated 7306 (VIM-VAR) 20 µm filtated L 10 theoetical Longe than theoetical life (pesence of fatigue load limit) Numbe of epeated stess, cycles Conventional theoy Lifetime M50, 6 µm filtated Fig. 1.2 NSK s New Life Theoy That Consides Fatigue Limit NSK s new life theoy P u : fatigue load limit (2) Suface oiginated flaking Unde actual beaing opeation, the lubicant is often contaminated with foeign objects such as metal chips, bus, cast sand, etc. When the foeign paticles ae mixed in the lubicant, the paticles ae pessed onto the aceways by the olling elements and dents occu on the sufaces of the aceways and olling elements. Stess concentation occus at the edges of the dents, geneating fine cacks, which ove time, popagate into flaking of the aceways and olling elements. As shown in Fig. 1.3, the actual life is shote than conventional calculated life, unde conditions of contaminated lubication at low max suface pessue. The actual life line sepaates fom the line ceated by theoetical life calculations and moves towads a shote life. This esult shows that the actual life unde contaminated lubication is futhe shotened compaed to the theoetical life because of the decease in maximum suface contact pessue. Table 1.3 Value of Contamination Coefficient a c Application examples Fig. 1.3 Life Test Result unde Contaminated Lubication Condition Max suface contact pessue, MPa Debis size µm Hadness 870HV L 10 theoetical Numbe of epeated stess, cycles Theefoe, the NSK new life calculation fomula consides the tend in the esults of the life test unde conditions of clean envionment and at low load zone. Based on these esults, the new life equation is a function of (P-P u )/C, which is affected by specific lubication conditions identified by the lubication paamete. Also, it is assumed that effects of diffeent types and shapes of foeign paticles ae stongly influenced by the beaing load and lubication conditions pesent, and that such a elationship can be expessed as a function of the load paamete. This elationship of the new life calculation fomula is defined by (P-P u )/C 1/a c. Calculation fomula fo suface oiginated flaking, based on the above concept, is as follows: Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Shote than theoetical life 1 (τ τ 1n N e u ) c dv { 1 h f (a 1 S Z o c,a L ) } V Vey clean Clean Nomal Contaminated Heavily contaminated a c facto Application µm 10 µm filtation µm filtation guide filtation Sealed gease lubicated beaing fo electical appliances and infomation technology equipment, etc. Sealed gease lubicated beaing fo electic motos Sealed gease beaing fo ailway axle boxes and machine tools, etc. V = stess volume Nomal usage Automotive hub unit beaing, etc. Geate than 100 µm filtation o no filtation (oil bath, ciculating lubication, etc.) Beaing fo automotive tansmission; Beaing fo industial geabox; Beaing fo constuction machine, etc. The contamination coefficient in tems of lubication cleanliness is shown in Table 1.3. Test esults on ball and olle beaings with gease lubication and clean filtation show the life as being a numbe of times longe than that of the contaminated calculation. Yet when the foeign object is hade than Hv350, hadness becomes a facto and a dent appeas on the aceway. Fatigue damage fom these dents, can pogess to flaking in a shot time. Test esults on ball and olle beaings unde conditions of foeign object contamination show fom 1/3 to 1/10 the life when compaed with conventionally calculated life. Based on these test esults, the contamination coefficient a c is classified into five steps fo NSK s new life theoy. (3) New life calculation fomula The following fomula, which combines sub-suface oiginated flaking and suface oiginated flaking, is poposed as the new life calculation fomula. 1 (τ τ 1n N e u ) c dv { 1 h S Z o f (a c,a L ) } L able = a 1 a NSK L 10 V No filtation, pesence of many fine paticles Life

74 1. LIFE Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Life Coection Facto a NSK The life coection facto a NSK is the function of lubication paamete (P-P u )/C 1/a c as shown below: a NSK F { a L,, P-P ( u C a c )} NSK s new life theoy consides the life extending affect of Fig. 1.4 New Life Calculation Diagam fo Ball Beaings a NSK K= 1 K= 0.5 K= 4 K= 2 Life of High Speed Beaings When beaings opeate at high speed, in addition to the extenal load, the intenal load geneated by the centifugal foce acting on the olling element must be taken into account. A compute should be used fo the calculation of the load conditions on beaings opeation at high speeds (in excess of d m n). Life of Ceamic Hybid Beaings C, C o valves and L 10 standads do not exist in ISO281 fo ceamic beaings. Howeve, ceamic beaing life tends to be longe than that of conventional steel ball beaings, unde the same appopiate opeating conditions. This may be especially tue in the situations whee the Life impoved mateial and heat teatment by coecting the contamination facto a c. The theoy also utilizes viscosity atio k (k = v/v 1 whee v is the opeational viscosity and v 1 the 0.1 K= 0.15 K= 0.1 Balance among the foces acting on the olling elements and inne/oute ings as well as changes in contact angle ae obtained by using convegence calculations( 1 ), based on the centifugal foce on the balls ae significant. equied viscosity) because the lubication paamete a L changes with the degee of oil film fomation, based on the lubicant and opeating tempeatue. The theoy indicates that (P P u) /C 1/a c load condition of the beaing (adial load, axial load, centifugal foce on olling elements, etc.). the bette the lubication conditions (highe k) the longe the life. Figues 1.4 and 1.5 show the diagams of the coection facto a NSK as a function of the new life calculation fomula. Also in Fig. 1.5 New Life Calculation Diagam fo Rolle Beaings K= 1 K= 4 K= 2 Life is initially calculated fo each individual olling element unde load between inne and oute ing and then the life of the entie single ow of beaing is obtained. ( 1 ) Convegence calculations allow NSK to calculate with geat this new life calculation fomula, point contact and line contact ae consideed sepaately fo ball and olle beaings espectively. New Life Calculation Fomula L able a NSK K= 0.5 K= 0.15 K= 0.1 accuacy the centifugal foce exeted on balls and to actually pefom load calculations fo each olling element. Fo life calculations on beaings used in high speed applications, please contact NSK. The concept of new life calculation fomula is simplified into one facto as shown by the fomula below in which conventional life calculation fomula (L 10 ) is multiplied with (P P u) /C 1/a c coection facto (a NSK ) and eliability facto (a 1 ; Table 1.4): Fig. 1.6 Change in Contact Angle Due to Centifugal Foce L able = a 1 a NSK L 10 Table 1.4 Reliability Facto Reliability (%) Reliability Facto To Access the NSK Calculation Tools Visit ou website at αe Oute ing FC α i Inne ing F C : The Centifugal Foce Applied to The Rolling Elements

75 2. STATIC LOAD RATINGS AND STATIC EQUIVALENT LOADS Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Static Load Ratings When subjected to an excessive load o a stong shock load, olling beaings may incu a local pemanent defomation of the olling elements and aceway suface if the elastic limit is exceeded. The nonelastic defomation inceases in aea and depth as the load inceases, and when the load exceeds a cetain limit, the smooth unning of the beaing is impeded. The basic static load ating is defined as that static load which poduces the following calculated contact stess at the cente of the contact aea between the olling element subjected to the maximum stess and the aceway suface. Fo ball beaings : 4 200MPa Fo olle beaings : 4 000MPa In this most heavily contacted aea, the sum of the pemanent defomation of the olling element and that of the aceway is nealy times the olling element s diamete. The basic static load ating C 0 is witten C 0 fo adial beaings and C 0a fo thust beaings in the beaing tables. Static Equivalent Loads The static equivalent load is a hypothetical load that poduces a contact stess equal the maximum stess unde actual conditions, while the beaing is stationay (including vey slow otation o oscillation), in the aea of contact between the most heavily stessed olling element and beaing aceway. The static adial load passing though the beaing cente is taken as the static equivalent load fo adial beaings, while the static axial load in the diection coinciding with the cental axis is taken as the static equivalent load fo thust beaings. Static equivalent load on adial beaings. The geate of the two values calculated fom the following equations should be adopted as the static equivalent load on adial beaings. P 0 = X 0 F + Y 0 F a P 0 = F Static equivalent load on thust beaings: P 0 = X 0 F + F a α 90 Pemissible Axial Loads In ode to optimize beaing pefomance, NSK has defined the pemissible axial loads statistically, based on the following 2 situations: 1 --The limiting load at which a contact ellipse is geneated between the ball and aceway due to a change in the contact angle when a adial beaing, which is unde an axial load, ides ove the shoulde of the aceway goove. 2 --The value of a static equivalent load P 0 which is detemined fom the basic static load ating C 0 using static axial load facto Y 0. The pemissible axial load is detemined by the lowe of the two values defined above. This value has been poven though expeience, and includes a safety facto. (Refe to the beaing tables fo pemissible axial loads) Fig. 2.2 Contact Ellipse and the Limiting Axial Loads Static Load Ratings and Static Equivalent Loads Fig. 2.1 The Relation between Indentations and Basic Static Load Rating Q Dw Table 2.1 Static Equivalent Load P 0 = X 0 F + Y 0 F a Contact Single DT DB o DF Angle X 0 Y 0 X 0 Y whee P 0 : Static equivalent load (N) F : Radial load (N) F a : Axial load (N) X 0 : Static adial load facto Y 0 : Static axial load facto a α Q Y When single o DT mounting and F > 0.5F + Y 0 F a, use P 0 = F Y Q = D w 1 2 Pemissible Static Load Facto The pemissible static equivalent load on beaings vaies depending on the basic static load ating and also thei application and opeating conditions. The pemissible static load facto is a safety facto that is applied to the basic static load ating, and it is defined by the atio in equation below: f S = (C 0 /P 0 ) whee C 0 : Basic static load ating (N) P 0 : Static equivalent load (N) Table 2.2 Values of Pemissible Static Load Facto f s 146 Opeating conditions Lowe limit of f s Ball beaings Rolle beaings Low-noise applications Beaings subjected to vibation and shock loads Standad opeating conditions

76 3. ANGULAR CONTACT BALL BEARING COMBINATIONS Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Angula Contact Ball Beaing Combinations Available Nomally, NSK supplies matched supe pecision angula contact ball beaings as 2, 3, and 4 ow combinations. The combinations available fo the fixed end of spindles ae usually 2 ows (DB), 3 ows (DBD), and 4 ows (DBB) sets. Howeve, in the case of 3 ow combinations, since the peload distibution to each beaing is not equal, the optimum peload setting ange is vey limited, making them unsuitable fo high speed applications. Matched beaings ae manufactued as sets, so when they ae mounted adjacent to each othe, a given peload is automatically obtained. The vaiation pe pai of matched beaings fo boe and oute diametes is adjusted to less than 1/3 of the pemissible toleance. Table 3.1 Featues of Each Combination Load diection Moment stiffness Speed capability Heat geneation Stiffness DB DF DT DBD DBB Excellent Vey good Good Fai One diection only Two diections Shaft Bending Compaison between Back-to-back and Face-to-face Aangements Moment stiffness is diffeent between Back-to-back and Faceto-face aangements as shown in the shaft bending compaison calculation example below. In this example, angula contact ball beaings (75BNR10XET) ae used in the font side and the typical shaft deflections ae shown fo both DB and DF configuations. When N of adial load is applied on the spindle nose, adial displacements on the spindle nose ae calculated as follows. σ DB = σ DF = This demonstates the effect of the distance between effective load centes on spindle bending. Fig. 3.4 Spindle Displacement Cuve DF Aangement DB Aangement Radial Load: N Angula Contact Ball Beaing Combinations Featues of Each Combination Back-to-back Aangement, DB Axial loads in both diections and adial loads can be sustained. Since the distance between the effective load centes is lage, this type is suitable if moments ae applied. Howeve, if accuacy of housing is not enough and thee is a misalignment in the spindle, intenal loads of beaings could be lage enough to possibly cause pematue failue due to geate moment stiffness. Fig. 3.1 The Distance between the Effective Load Centes of Back-to-back and Face-to-face Aangements Mounting Instuctions fo Angula Contact Ball Beaings Matching Method Diection of Matching Fo matched beaings, the mounting ode and load application diection ae vey impotant. A V is maked on the oute diamete sufaces of the beaings as shown in the figue on the ight. When the beaings ae mounted so thei maks coectly fom a V, they ae popely matched and aligned. On the side suface o chamfeed pat of the inne ings, the symbol is maked to indicate the position of maximum adial unout. Optimum accuacy is achieved when the beaing is mounted so the symbol is placed just opposite the position of shaft maximum eccenticity. Fig. 3.6 Combinations of Angula Contact Ball Beaings DB DF DT Face-to-face Aangement, DF Compaed with the DB type, the distance between the effective load centes is small, so the capacity to sustain moments is infeio to the DB type. On the othe hand, this type is suitable fo using with housings that have less accuacy o lage shaft deflections due to low bending stiffness of shaft. The distance between the effective load centes DB The distance between the effective load centes DF Fig. 3.2 Load Diection in Back-to-Back and Tandem Aangements DBD DFD DTD Tandem Aangement, DT Axial loads in one diection and adial loads can be sustained. Since axial stiffness of this type is twice the value of a single ow type, this aangement is used when the axial load in one diection is heavy. Fig. 3.5 The Symbol fo the Position of Maximum Radial Runout of Inne Ring DBB DFF DBT 3 ows Aangement, DBD Axial loads in both diections and adial loads can be sustained. Howeve, the peload distibution to each beaing is not equal, and peload on the counte side (single side) is twice that of othe side. Consequently, this type is unsuitable fo high speed opeation because of the lage incease of intenal load of the single side which could lead to beaing failue. DB Fig. 3.3 Intenal Peload in DBD Aangement Peload=500 N DT DFT DTT 4 ows Aangement, DBB Axial loads in both diections and adial loads can be sustained. In situations that have the same axial cleaance as DB aangement, peload and stiffness ae twice that of the DB aangement. Also, the pemissible axial load of a 4 ow aangement is lage than that of a DB aangement. 250 N 250 N 500 N

77 3. ANGULAR CONTACT BALL BEARING COMBINATIONS Univesal Combination NSK supplies univesal combination angula contact ball beaings that have the same amount of stand out on both the font and back face. This means that when beaings that have the same efeence numbe ae combined, they have the specified amount fo each standad peload. Fo univesal combination beaings, the V combination maks on the oute diamete suface of oute ing pevent diection mistakes, ensue coect matching when they ae mounted, and indicate the diection of the contact angle. Fig. 3.7 Univesal Combination f Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Notice fo Use of Single Univesal (SU) Beaings When these beaings ae used as pat of multiple combined beaings, it is ecommended that the vaiation of boe and oute diamete toleance is within 1/3 of toleance ange. Thee ae also special beaings with special accuacy Class 4Y that can accommodate small vaiations of boe and oute diamete toleance. Class 4Y toleance has the same unning accuacy as Class 4 but has a naowe toleance ange of boe and oute diamete than Class 4. It is suitable fo andom matching method univesal combination beaings. Class 4Y is suitable fo use andom matching method univesal combination beaings. Howeve, when these beaings ae opeated ove d m n, thee is a possibility that this vey small vaiation of fits with eithe the shaft o the housing can cause beaing failue because of imbalance of intenal load in each ow. If these beaings ae consideed fo such high speed applications, this issue should be taken into account. Fig. 3.8 Toleance of P4 and P4Y Accuacy Applicable to any aangement because f (stand out of font face) is same as b (stand out of back face). b Vaiation of boe toleance Vaiation of oute diamete toleance Toleance Range of P4Y Toleance Range of P4 Toleance Range of P4 Toleance Range of P4Y Angula Contact Ball Beaing Combinations Negative Cleaance: 2f When beaings ae mounted in andom matching method, vaiation of toleance should be consideed. Negative Cleaance: 2b DB aangement Peload is stand out of back face x 2 = 2b (=2f) and it is the specified amount fo each standad peload. Diffeence between SU and DU Beaings DF aangement Peload is stand out of font face x 2 = 2f (=2b) and it is the specified amount fo each standad peload. Thee ae 2 types of NSK univesal combination beaings as shown in the table below. Table 3.2 Featues of SU and DU Beaings DT aangement Thee is no cleaance on DT suface because stand out of font face f is same as stand out of back face b. This situation is the same as beaings combined as DT. SU DU Row of beaings 1 2 Vaiation of boe and oute diamete toleance Contolled in 1/3 of toleance Combination Mak and Matching Method fo Univesal Combination Beaings Boe and Oute Diamete Toleance (Class 4Y) Fig. 3.9 Univesal Beaings Combinations DBD DB DF DT DFD DTD DBB DFF DBT Table 3.3 Toleance of Boe Diamete of Inne Ring Unit: µm Boe diamete Class 4 Class 4Y (Contolled to medium value) Ove Incl High Low High Low Toleances fo beaings unde 30 mm boe ae the same as values quoted between mm boe. Table 3.4 Toleance of Oute Diamete of Oute Ring Unit: µm Oute diamete Class 4 Class 4Y (Contolled to medium value) Ove Incl High Low High Low Unde Toleances fo beaings unde 50 mm oute diamete ae the same as values quoted between mm oute diamete. DFT DTT

78 4. PRELOAD AND RIGIDITY Regading the igidity of machine tool spindles, it is possible to think of the beaings as being spings. Axial displacement, when an axial load is applied to the spindle, is detemined by the axial igidity of the fixed end beaings. When high adial igidity is equied, cylindical olle beaings ae geneally used. Axial loads ae usually sustained by angula contact ball beaings. The bigge the contact angle of the angula contact ball beaings, the highe the axial igidity. Beaings of the same boe size, which have moe olling elements (diamete seies 0 o 9; o BNR10 o BNR19 seies), have highe igidity, even though the diamete o the olling elements is smalle. Nomally, peload is applied to beaings in ode to incease igidity of machine tool spindles. But if the peload is excessively high, flaking and possible seizue will esult. Many uses incease igidity by using a combination of two o moe angula contact ball beaings. This is especially tue fo ball scew suppot beaings, whee high igidity is equied, the contact angle is big, and peload is highe than that fo a spindle. Axial loads ae widely sustained with two o thee beaings. Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Change of Rigidity by Peload Position Peload and Axial Rigidity When the inne ings of the duplex beaings shown in Fig. 4.3 ae fixed axially, beaings A and B ae displaced δ aoa and δ aob and axial space δ ao between the inne ings is eliminated. With this condition, a peload F ao is imposed on each beaing. The elation between axial load, F a and displacement in a duplex set is shown in Fig Figues 4.5 and 4.6 illustate the same concepts fo a DBD aangement. Back-to-Back Aangement (DB) DBD Aangement Fig. 4.3 Peloaded DB Aangement Fig. 4.5 Peloaded DBD Aangement Beaing A Beaing B Beaing AA side Beaing B side Fao Fao Fao Fao Fa δ ao Fa δ ao Pupose The main puposes of peloaded beaings in a machine tool spindle ae as follows: To impove and maintain the unning accuacy of the shaft. peload, thus isking vetical displacement (tilting) of the beaing.) Fig. 4.1 Position Peload δ aoa δ aob Fig. 4.4 Peloaded Axial Displacement of DB Aangement δ aoa δ aob Fig. 4.6 Peloaded Axial Displacement of DBD Aangement Peload and Rigidity To incease beaing igidity. To minimize noise due to axial vibation and esonance. To pevent false binelling. To pevent sliding between the olling elements and aceways due to gyoscopic moments. To maintain the olling elements in thei pope position. Usually a peload is applied to beaings by using two o moe beaings in combination with each othe, such as angula contact ball beaings o tapeed olle beaings. Cylindical olle beaings can be peloaded by making the (2) Constant Pessue Peload Beaing B Fao δ aa Axial load δ a δ ab Beaing A Fa FaA FaB Axial displacement Displacement of one beaing on side B Axial load δ a Displacement of both beaings on side AA Fa Displacement of one beaing on side AA FaA adial intenal cleaance negative. A constant pessue peload is achieved using a coil o leaf δ aoa δ aob Fao (1) Position Peload A position peload is achieved by fixing two axially opposed beaings in a position that emains unchanged while in opeation. In pactice, the following thee methods ae geneally used to obtain a position peload. sping. Even if the elative position of the beaings change duing opeation, the magnitude of the peload emains elatively constant. An angula contact ball beaing aangement fo high speed otation is shown in Fig Side A Side B δ aa δ aoa Side AA δ ao δ ab δ aob Side B FaB Axial displacement 1. By installing a duplex beaing set with peviously adjusted stand-out dimensions and axial cleaance 2. By using a space o shim of pope size to obtain the equied spacing and peload (see Fig. 4.1). 3. By utilizing bolts o nuts to allow adjustment of the axial peload (In this case, the stating toque should be Fig. 4.2 Constant Pessue Peload F a F aa F ab δ a δ aa δ ab : Axial load applied fom outside : Axial load imposed on Beaing A : Axial load imposed on Beaing B : Displacement of duplex set : Displacement of Beaing A : Displacement of Beaing B F a F aa F ab δ a δ aa δ ab : Axial load applied fom outside : Axial load imposed on Beaing AA : Axial load imposed on Beaing B : Displacement of tiplex set : Displacement of Beaing AA : Displacement of Beaing B measued to veify the pope peload. Howeve, this method cannot be ecommended fo high pecision machine tool spindles due to difficulty in veifying the pope

79 4. PRELOAD AND RIGIDITY Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Constant Pessue Peload and Axial Rigidity Fig. 4.7 illustates duplex beaing unde constant pessue peload. The deflection cuve of the sping is nealy paallel to the hoizontal axis due to the igidity of the spings being smalle than that of the beaing. As a esult, igidity unde constant pessue peload is appoximately equal to that fo a single beaing with a peload of F ao being applied to it. Fig. 4.8 compaes the igidity of a beaing with position peloading and one with constant pessue peloading. Fig. 4.7 Axial Displacement with Constant Pessue Peload Axial load δ a δ ao δ aa Axial load Beaing with position peload δ a Fa Fao Fig. 4.8 Compaison of Stiffness and Peloading Beaing with constant pessue peload Axial displacement Beaing without peload δ a Fa δ a Beaing A Axial displacement Compaison of Peloading Methods Position peload and constant pessue peload can be compaed as follows: (1) When both of the peloads ae equal, the position peload povides geate beaing igidity. In othe wods, the deflection due to extenal loads is less fo beaings with a position peload. (2) Unde position peload, the peload vaies depending on such factos as a diffeence in axial expansion due to a tempeatue diffeence between the shaft and housing, a diffeence in adial expansion due to a tempeatue diffeence between the inne and oute ings, and deflection due to load. Unde constant pessue peload, it is possible to minimize any change in peload because the vaiation of the sping load with shaft expansion and contaction is negligible. Fom the foegoing explanation, it is seen that position peloads ae geneally pefeed fo inceasing igidity while constant pessue peloads ae moe suitable fo high speed applications. Peload Amount A lage peload esults in highe igidity. Howeve, if peload is lage than necessay, abnomal heat is geneated, which educes fatigue life. In exteme cases, it may esult in excessive wea o even seizue. Theefoe, the amount of peload should be caefully studied and selected to avoid excessive peload while taking into consideation the type of application and the opeating conditions. High Speed Spindles and Peload When beaings opeate at high speed, the contact suface pessue between the balls and the inne and oute ing aceways inceases due to expansion of the intenal axial load caused by centifugal foce, geneation of intenal axial load caused by centifugal foce on the balls, and tempeatue diffeence between inne and oute ings. Fo beaings having a contact angle, such as angula contact ball beaings, pue olling motion with sliding due to spin moments and gyoscopic moments on the balls may occu. Sliding inceases as beaing speed inceases. As a esult, the intensity of heat geneated in the contact aeas inceases and the viscosity of the lubicating oil deceases. In some cases, a beakdown of the oil film occus, esulting in complete seizue of the beaing. In othe wods, if the contact suface pessue at low speed opeation is equal to that of high speed opeation, then heat geneation, which is due to sliding at high speeds, becomes moe intense. This concept can be expessed quantitatively as a Pvvalue, whee P is the contact suface pessue, and v is the slip ate. The Pv value can be applied to the olling contact aea of the beaing. If the Pv value is constant, sliding is geate at high speed opeation than at low speed opeation. Wheeas velocity is inceased, it becomes necessay to educe the contact suface pessue. NSK can calculate contact suface pessue and slip ate geneated duing high speed opeations by compute. Taking advantage of abundant empiical test data and actual maket esults, we can detemine the peload accoding to limiting factos, which ae based on the lubicating method and otating speed. Fo opeations exceeding 800,000 d m n, please contact NSK. Special Cleaance Fo special cleaance of combined angula contact ball beaings, NSK offes both CA and CP cleaances. CA: axial cleaance (Cleaance exists in the axial diection) CP: peload cleaance (Peload is geneated) Fig. 4.9 Special Cleaance + a Axial cleaance (CA) a Peload cleaance (CP) Peload Adjustment When you change peload (fo example EL L ), please adjust the diffeence of the measued axial cleaance, by a space. (When inceasing peload, inne space should be shote, and oute space should be shote when deceasing peload) Please efe to Pages of the measued axial cleaances. Please efe the measuing load of axial cleaance to Table 4.1. Table 4.1 Measuing load of axial cleaance Nominal Outside Diamete (mm) Ove Incl Measuing load (N) Applied to the beaing with the O. D. less than 10 mm. Fig Radial Cleaance in Double Row Cylindical Rolle Beaing and Vaiation of Rolling Fatigue Life Life atio Radial displacement, mm Beaing : NN3020 Radial load : N Radial cleaance, mm Fig Radial Cleaance in Double Row Cylindical Rolle Beaing and Vaiation of Rigidity Beaing : NN3020 Radial load : N Radial cleaance, mm Intenal Cleaance in Cylindical Rolle Beaings In ode fo machine tool spindles to have high unning accuacy and igidity, beaings ae used with minimum intenal cleaance o peload afte mounted. Cylindical olle beaings with tapeed boes ae usually used to allow easie adjustment of intenal cleaance. In geneal, cylindical olle beaings fo the font end (fixed end) of the spindle ae adjusted to apply a peload duing opeating. Beaing fo the ea end (fee end) ae adjusted when mounted to poduce a slight cleaance duing opeating. The amount of adial intenal cleaance afte mounted is based on seveal factos such speed, load, lubicating method, beaing size, equied igidity, life, etc. Fig illustates the elation between adial intenal cleaance in a beaing and life. Fig shows the elation between adial intenal cleaance and adial elastic displacement of an NN3020 (Boe diamete 100 mm, outside diamete 150 mm, width 37 mm). Peload and Rigidity

80 4. PRELOAD AND RIGIDITY Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Peload and Rigidity (DB and DF Aangement) High Pecision Angula Contact Ball Beaings (Standad seies) Calculation of adial igidity Multiply axial igidity by factos in table A. Table A EL L M H Calculation of peload and axial igidity fo combination beaings Multiply by factos in table B. Fo adial igidity, multiply the value obtained in table A with factos in table B. Table B DBD DBB Peload facto Axial igidity Radial igidity seies, C angle Nominal contact angle 15 Steel ball and Ceamic ball 70 seies, C angle Nominal contact angle 15 Steel ball and Ceamic ball Nominal EL L M H Boe Numbe Beaing Boe Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (5) (2) ( 1) ( 6) (4) (2) ( 3) ( 8) (3) (0) ( 4) ( 11) (3) (0) ( 5) ( 12) (1) ( 3) ( 8) ( 15) (1) ( 2) ( 9) ( 17) (0) ( 3) ( 9) ( 16) (2) ( 2) ( 9) ( 18) (1) ( 3) ( 12) ( 22) (0) ( 5) ( 12) ( 21) (0) ( 4) ( 14) ( 24) ( 1) ( 6) ( 15) ( 26) ( 1) ( 5) ( 14) ( 25) ( 2) ( 7) ( 16) ( 27) ( 4) ( 10) ( 22) ( 35) ( 4) ( 10) ( 21) ( 35) ( 4) ( 9) ( 21) ( 34) ( 6) ( 13) ( 25) ( 41) ( 3) ( 9) ( 23) ( 39) ( 3) ( 9) ( 24) ( 40) ( 5) ( 13) ( 27) ( 46) ( 5) ( 13) ( 27) ( 45) ( 5) ( 13) ( 27) ( 45) ( 8) ( 17) ( 35) ( 56) ( 10) ( 20) ( 38) ( 61) ( 10) ( 19) ( 37) ( 60) ( 7) ( 18) ( 38) ( 63) ( 8) ( 19) ( 39) ( 64) ( 9) ( 20) ( 40) ( 65) ( 12) ( 25) ( 48) ( 78) ( 12) ( 25) ( 49) ( 79) ( 16) ( 31) ( 58) ( 92) 493 Nominal EL L M H Boe Numbe Beaing Boe Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (3) (0) ( 5) ( 12) (3) (0) ( 6) ( 14) (3) ( 1) ( 7) ( 16) (2) ( 1) ( 7) ( 16) (0) ( 4) ( 12) ( 22) ( 1) ( 5) ( 14) ( 24) (1) ( 3) ( 13) ( 24) ( 1) ( 7) ( 16) ( 28) ( 1) ( 6) ( 17) ( 30) ( 3) ( 8) ( 19) ( 33) ( 2) ( 8) ( 20) ( 34) ( 4) ( 11) ( 24) ( 40) ( 4) ( 11) ( 26) ( 42) ( 6) ( 13) ( 24) ( 39) ( 7) ( 14) ( 30) ( 48) ( 7) ( 14) ( 31) ( 49) ( 6) ( 14) ( 31) ( 52) ( 6) ( 14) ( 32) ( 52) ( 8) ( 18) ( 37) ( 60) ( 9) ( 19) ( 36) ( 58) ( 9) ( 18) ( 37) ( 60) ( 11) ( 21) ( 42) ( 67) ( 13) ( 25) ( 49) ( 78) ( 14) ( 26) ( 50) ( 79) ( 16) ( 29) ( 54) ( 85) ( 11) ( 24) ( 47) ( 77) ( 13) ( 27) ( 52) ( 84) ( 14) ( 29) ( 57) ( 90) ( 18) ( 35) ( 66) ( 104) ( 21) ( 39) ( 71) ( 111) ( 23) ( 42) ( 76) ( 119) ( 25) ( 45) ( 81) ( 126) 533 Peload and Rigidity 79 seies, A5 angle Nominal contact angle 25 Steel ball and Ceamic ball 70 seies, A5 angle Nominal contact angle 25 Steel ball and Ceamic ball Nominal EL L M H Boe Numbe Beaing Boe Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (2) (1) ( 3) ( 6) (1) ( 1) ( 3) ( 7) (1) ( 1) ( 4) ( 9) (1) ( 1) ( 4) ( 8) (0) ( 3) ( 6) ( 12) ( 1) ( 3) ( 7) ( 12) ( 1) ( 3) ( 6) ( 11) (0) ( 3) ( 8) ( 15) ( 1) ( 3) ( 9) ( 16) ( 1) ( 4) ( 10) ( 17) ( 1) ( 4) ( 10) ( 18) ( 2) ( 5) ( 11) ( 18) ( 2) ( 5) ( 10) ( 18) ( 2) ( 5) ( 11) ( 18) ( 3) ( 7) ( 14) ( 24) ( 3) ( 7) ( 15) ( 24) ( 4) ( 8) ( 15) ( 25) ( 5) ( 9) ( 17) ( 29) ( 4) ( 8) ( 16) ( 27) ( 3) ( 8) ( 17) ( 28) ( 5) ( 10) ( 19) ( 31) ( 4) ( 9) ( 19) ( 32) ( 5) ( 10) ( 20) ( 33) ( 7) ( 13) ( 24) ( 39) ( 7) ( 14) ( 25) ( 41) ( 7) ( 13) ( 26) ( 42) ( 7) ( 14) ( 28) ( 47) ( 7) ( 14) ( 29) ( 47) ( 8) ( 15) ( 29) ( 48) ( 10) ( 19) ( 35) ( 57) ( 10) ( 19) ( 35) ( 57) ( 12) ( 22) ( 41) ( 66) When a ceamic ball is used, Peload and axial igidity value will be 1.2 times the value of steel ball. The value in ( ) shows a measued axial cleaance. Nominal EL L M H Boe Numbe Beaing Boe Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (1) ( 2) ( 5) ( 10) (1) ( 2) ( 6) ( 12) (1) ( 1) ( 6) ( 11) (0) ( 2) ( 7) ( 13) ( 1) ( 4) ( 10) ( 17) ( 2) ( 5) ( 9) ( 16) ( 1) ( 4) ( 10) ( 18) ( 1) ( 5) ( 12) ( 21) ( 2) ( 6) ( 12) ( 21) ( 2) ( 6) ( 13) ( 22) ( 3) ( 7) ( 14) ( 24) ( 4) ( 9) ( 18) ( 29) ( 4) ( 9) ( 17) ( 28) ( 5) ( 9) ( 18) ( 29) ( 6) ( 11) ( 20) ( 33) ( 6) ( 11) ( 21) ( 34) ( 6) ( 11) ( 23) ( 37) ( 5) ( 11) ( 22) ( 36) ( 7) ( 13) ( 25) ( 41) ( 7) ( 13) ( 25) ( 42) ( 7) ( 13) ( 26) ( 42) ( 8) ( 15) ( 28) ( 46) ( 10) ( 18) ( 33) ( 53) ( 10) ( 18) ( 33) ( 54) ( 12) ( 20) ( 36) ( 58) ( 9) ( 18) ( 35) ( 56) ( 11) ( 20) ( 37) ( 61) ( 12) ( 22) ( 40) ( 65) ( 14) ( 25) ( 47) ( 75) ( 16) ( 28) ( 50) ( 80) ( 17) ( 29) ( 53) ( 85) ( 18) ( 31) ( 56) ( 90) When a ceamic ball is used, Peload and axial igidity value will be 1.2 times the value of steel ball. The value in ( ) shows a measued axial cleaance

81 4. PRELOAD AND RIGIDITY Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Peload and Rigidity (DB and DF Aangement) High Pecision Angula Contact Ball Beaings (Standad seies) Calculation of adial igidity Multiply axial igidity by factos in table A. Table A EL L M H Calculation of peload and axial igidity fo combination beaings Multiply by factos in table B. Fo adial igidity, multiply the value obtained in table A with factos in table B. Table B DBD DBB Peload facto Axial igidity Radial igidity seies, A angle Nominal contact angle 30 Steel ball 72 seies, C angle Nominal contact angle 15 Steel ball Nominal EL L M H Boe Numbe Beaing Boe Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (0) (-5) ( 10) ( 15) (0) (-5) ( 10) ( 15) (0) (-5) ( 10) ( 15) (0) (-5) ( 10) ( 15) (0) (-5) ( 10) ( 15) (0) (-5) ( 10) ( 15) (0) (-5) ( 10) ( 15) (0) ( 5) ( 10) ( 15) (0) ( 5) ( 10) ( 15) (0) ( 5) ( 10) ( 20) (0) ( 5) ( 10) ( 20) (0) ( 5) ( 15) ( 20) (0) ( 5) ( 15) ( 20) (0) ( 5) ( 15) ( 20) (0) ( 5) ( 16) ( 25) (0) ( 5) ( 15) ( 25) (0) ( 10) ( 20) ( 30) (0) ( 10) ( 20) ( 30) (0) ( 10) ( 25) ( 35) (0) ( 10) ( 25) ( 35) (0) ( 10) ( 25) ( 35) (0) ( 10) ( 25) ( 35) (0) ( 15) ( 30) ( 45) (0) ( 15) ( 30) ( 45) (0) ( 15) ( 35) ( 50) (0) ( 15) ( 35) ( 50) (0) ( 15) ( 37) ( 60) (0) ( 15) ( 35) ( 60) (0) ( 20) ( 37) ( 60) (0) ( 24) ( 40) ( 64) (0) ( 25) ( 43) ( 69) (0) ( 30) ( 60) ( 95) The value in ( ) shows a measued axial cleaance. Nominal EL L M H Boe Numbe Beaing Boe Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (3) ( 1) ( 8) ( 18) (1) ( 3) ( 12) ( 22) (1) ( 3) ( 11) ( 21) (0) ( 4) ( 16) ( 28) ( 2) ( 7) ( 20) ( 33) (1) ( 4) ( 15) ( 26) ( 1) ( 8) ( 20) ( 35) ( 3) ( 10) ( 25) ( 43) ( 5) ( 13) ( 29) ( 47) ( 7) ( 16) ( 30) ( 49) ( 7) ( 15) ( 31) ( 50) ( 8) ( 17) ( 38) ( 60) ( 11) ( 22) ( 42) ( 67) ( 12) ( 23) ( 44) ( 70) ( 9) ( 20) ( 43) ( 69) ( 10) ( 21) ( 42) ( 68) ( 12) ( 24) ( 47) ( 76) ( 14) ( 27) ( 53) ( 85) ( 15) ( 29) ( 57) ( 90) ( 18) ( 33) ( 63) ( 99) ( 20) ( 36) ( 68) ( 107) ( 21) ( 38) ( 73) ( 114) ( 24) ( 43) ( 78) ( 121) ( 19) ( 38) ( 73) ( 116) ( 20) ( 39) ( 73) ( 116) ( 24) ( 45) ( 82) ( 131) ( 28) ( 51) ( 92) ( 145) seies, A5 angle Nominal contact angle 25 Steel ball Nominal EL L M H Boe Numbe Beaing Boe Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (1) ( 2) ( 7) ( 13) ( 1) ( 3) ( 9) ( 16) ( 1) ( 4) ( 11) ( 19) ( 1) ( 4) ( 11) ( 18) ( 3) ( 6) ( 14) ( 24) ( 2) ( 5) ( 12) ( 22) ( 3) ( 7) ( 15) ( 25) ( 4) ( 8) ( 18) ( 30) ( 4) ( 9) ( 20) ( 33) ( 5) ( 10) ( 22) ( 37) ( 6) ( 11) ( 23) ( 37) ( 7) ( 13) ( 26) ( 42) ( 8) ( 15) ( 29) ( 47) ( 9) ( 15) ( 30) ( 48) ( 8) ( 15) ( 30) ( 49) ( 8) ( 15) ( 30) ( 49) ( 9) ( 17) ( 33) ( 54) ( 10) ( 19) ( 35) ( 57) ( 12) ( 21) ( 39) ( 64) ( 13) ( 23) ( 42) ( 68) ( 14) ( 25) ( 45) ( 73) ( 15) ( 27) ( 48) ( 77) ( 16) ( 29) ( 51) ( 82) ( 15) ( 28) ( 52) ( 85) ( 15) ( 28) ( 52) ( 83) ( 18) ( 32) ( 58) ( 93) ( 21) ( 36) ( 64) ( 104) 960 The value in ( ) shows a measued axial cleaance. Peload and Rigidity

82 4. PRELOAD AND RIGIDITY Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Peload and Rigidity (DB and DF Aangement) High Pecision Angula Contact Ball Beaings (Standad seies) 72 seies, A angle Nominal contact angle 30 Steel ball Calculation of adial igidity Multiply axial igidity by factos in table A. Table A EL L M H Ulta High Speed Angula Contact Ball Beaings (ROBUST seies) BNR19S, BNR29S Nominal contact angle 18 Steel ball Calculation of peload and axial igidity fo combination beaings Peload and axial igidity can be obtained by multiplying factos in table B. Fo adial igidity, multiply the value obtained in table A with factos in table B. Table B DBD DBB Peload facto Axial igidity Radial igidity Nominal EL L M H Boe Numbe Beaing Boe Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (0) ( 5) ( 10) (0) ( 5) ( 10) ( 15) (0) ( 5) ( 10) ( 15) (0) ( 5) ( 10) ( 15) (0) ( 10) ( 15) ( 20) (0) ( 10) ( 15) ( 20) (0) ( 10) ( 15) ( 20) (0) ( 10) ( 15) ( 25) (0) ( 10) ( 15) ( 26) (0) ( 10) ( 20) ( 30) (0) ( 10) ( 20) ( 30) (0) ( 10) ( 26) ( 35) (0) ( 10) ( 25) ( 35) (0) ( 10) ( 25) ( 35) (0) ( 15) ( 30) ( 40) (0) ( 15) ( 30) ( 40) (0) ( 15) ( 30) ( 40) (0) ( 16) ( 35) ( 50) (0) ( 20) ( 40) ( 50) ( 5) ( 20) ( 40) ( 55) ( 5) ( 20) ( 45) ( 60) ( 5) ( 25) ( 45) ( 65) ( 5) ( 25) ( 50) ( 70) ( 5) ( 25) ( 55) ( 70) ( 5) ( 30) ( 60) ( 75) ( 5) ( 36) ( 65) ( 80) ( 5) ( 35) ( 66) ( 81) High Pecision Angula Contact Ball Beaings (Miniatue seies) Nominal EL L M Beaing Boe Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (0) ( 8) ( 16) (0) ( 8) ( 15) (0) ( 8) ( 17) (0) ( 8) ( 16) (0) ( 8) ( 16) (0) ( 8) ( 16) (0) ( 8) ( 16) (0) ( 8) ( 16) (0) ( 8) ( 16) (0) ( 8) ( 16) (0) ( 8) ( 19) (0) ( 8) ( 19) (0) ( 8) ( 24) (0) ( 8) ( 21) (0) ( 8) ( 22) (0) ( 10) ( 26) (0) ( 10) ( 26) (0) ( 12) ( 26) (0) ( 12) ( 33) (0) ( 20) ( 35) (0) ( 20) ( 36) (0) ( 20) ( 38) 242 Peload and Rigidity Small size angula contact ball beaing 70, 72 seies, A angle Beaing numbes with a C suffix: nominal contact angle 15, 30 Steel ball BER19S, BER29S Nominal contact angle 25 Steel ball EL L M H Beaing Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity Numbe (N) (N/µm) (N) (N/µm) (N) (N/µm) (N) (N/µm) 725C 1.3 (10) (7) (4) (0) A 5.0 (3) (2) (0) ( 3) C 1.5 (10) (6) (3) ( 2) A 4.9 (3) (1) (0) ( 3) C 1.8 (9) (5) (2) ( 3) A 3.7 (3) (1) ( 1) ( 4) C 1.8 (9) (5) (2) ( 3) A 3.7 (3) (1) ( 1) ( 4) C 4.2 (7) (3) ( 1) ( 7) A 8.1 (2) (0) ( 2) ( 5) C 4.2 (7) (3) ( 1) ( 7) A 8.1 (2) ( 1) ( 2) ( 5) 63.4 The value in ( ) shows a measued axial cleaance. Nominal EL L M Beaing Boe Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (0) ( 8) ( 14) (0) ( 8) ( 14) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 8) ( 19) (0) ( 8) ( 17) (0) ( 8) ( 17) (0) ( 10) ( 20) (0) ( 10) ( 20) (0) ( 10) ( 20) (0) ( 12) ( 26) (0) ( 16) ( 27) (0) ( 16) ( 27) (0) ( 17) ( 30) 428 The value in ( ) shows a measued axial cleaance

83 4. PRELOAD AND RIGIDITY Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Peload and Rigidity (DB and DF Aangement) Ulta High Speed Angula Contact Ball Beaings (ROBUST seies) BNR19H, BNR19X, BNR19XE, BNR29H BNR29X Nominal contact angle 18 Ceamic ball Calculation of adial igidity Multiply axial igidity by factos in table A. Table A EL L M H BNR10S, BNR20S Nominal contact angle 18 Steel ball Calculation of peload and axial igidity fo combination beaings Peload and axial igidity can be obtained by multipling factos in table B. Fo adial igidity, multiply the value obtained in table A with factos in table B. Table B DBD DBB Peload facto Axial igidity Radial igidity Nominal EL L M Beaing Boe Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 8) ( 16) (0) ( 8) ( 17) (0) ( 8) ( 16) (0) ( 8) ( 16) (0) ( 8) ( 15) (0) ( 8) ( 16) (0) ( 8) ( 16) (0) ( 8) ( 16) (0) ( 8) ( 19) (0) ( 8) ( 19) (0) ( 8) ( 24) (0) ( 8) ( 21) (0) ( 8) ( 22) (0) ( 10) ( 26) (0) ( 10) ( 26) (0) ( 12) ( 26) (0) ( 12) ( 33) (0) ( 20) ( 35) (0) ( 20) ( 36) (0) ( 20) ( 38) 284 Nominal EL L M Beaing Boe Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (0) ( 5) ( 13) (0) ( 5) ( 12) (0) ( 5) ( 11) (0) ( 5) ( 11) (0) ( 5) ( 12) (0) ( 5) ( 14) (0) ( 5) ( 15) (0) ( 5) ( 15) (0) ( 10) ( 20) (0) ( 10) ( 20) (0) ( 10) ( 19) (0) ( 10) ( 19) (0) ( 10) ( 24) (0) ( 10) ( 24) (0) ( 10) ( 24) (0) ( 12) ( 27) (0) ( 15) ( 29) (0) ( 15) ( 29) (0) ( 20) ( 36) (0) ( 15) ( 30) (0) ( 18) ( 35) 253 Peload and Rigidity BER19H, BER19X, BER19XE, BER29H, BER29X Nominal contact angle 25 Ceamic ball Nominal EL L M Beaing Boe Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (0) ( 8) ( 14) (0) ( 8) ( 14) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 8) ( 14) (0) ( 8) ( 14) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 8) ( 19) (0) ( 8) ( 17) (0) ( 8) ( 17) (0) ( 10) ( 20) (0) ( 10) ( 20) (0) ( 10) ( 20) (0) ( 12) ( 26) (0) ( 16) ( 27) (0) ( 16) ( 27) (0) ( 17) ( 30) 504 The value in ( ) shows a measued axial cleaance. BER10S, BER20S Nominal contact angle 25 Steel ball Nominal EL L M Beaing Boe Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 10) ( 18) (0) ( 10) ( 18) (0) ( 10) ( 18) (0) ( 10) ( 18) (0) ( 12) ( 21) (0) ( 12) ( 22) (0) ( 12) ( 22) (0) ( 12) ( 22) (0) ( 12) ( 22) (0) ( 12) ( 22) (0) ( 15) ( 26) (0) ( 15) ( 26) (0) ( 15) ( 26) (0) ( 16) ( 27) (0) ( 13) ( 23) (0) ( 15) ( 28) 444 The value in ( ) shows a measued axial cleaance

84 4. PRELOAD AND RIGIDITY Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Peload and Rigidity (DB and DF Aangement) Ulta High Speed Angula Contact Ball Beaings (ROBUST seies) Calculation of adial igidity Multiply axial igidity by factos in table A. Table A EL L M H Ulta High Pecision Angula Contact Ball Beaings (ROBUST seies BGR) Calculation of peload and axial igidity fo combination beaings Peload and axial igidity can be obtained by multipling factos in table B. Fo adial igidity, multiply the value obtained in table A with factos in table B. Table B DBD DBB Peload facto Axial igidity Radial igidity BNR10H, BNR10X, BNR10XE, BNR20H, BNR20X Nominal contact angle 18 Ceamic ball BGR19S Nominal contact angle 15 Steel ball BGR19H, BGR19X Nominal contact angle 15 Ceamic ball Nominal EL L M Beaing Boe Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (0) ( 5) ( 11) (0) ( 5) ( 12) (0) ( 5) ( 11) (0) ( 5) ( 11) (0) ( 5) ( 12) (0) ( 5) ( 14) (0) ( 5) ( 15) (0) ( 5) ( 15) (0) ( 10) ( 20) (0) ( 10) ( 20) (0) ( 10) ( 19) (0) ( 10) ( 19) (0) ( 10) ( 24) (0) ( 10) ( 24) (0) ( 10) ( 24) (0) ( 12) ( 28) (0) ( 15) ( 29) (0) ( 15) ( 29) (0) ( 20) ( 36) (0) ( 15) ( 30) (0) ( 18) ( 35) 297 BER10H, BER10X, BER10XE, BER20H, BER20X Nominal contact angle 25 Ceamic ball EL Nominal Beaing Boe Peload Axial Rigidity (mm) (N) (N/µm) (0) (0) (0) (0) (0) (0) 20.6 BGR10S Nominal contact angle 15 Steel ball EL Nominal Beaing Boe Peload Axial Rigidity (mm) (N) (N/µm) 6 25 (0) (0) (0) (0) (0) (0) (0) (0) (0) 19.0 EL Nominal Beaing Boe Peload Axial Rigidity (mm) (N) (N/µm) (0) (0) (0) (0) (0) (0) 22.9 BGR10H, BGR10X Nominal contact angle 15 Ceamic ball EL Nominal Beaing Boe Peload Axial Rigidity (mm) (N) (N/µm) 6 25 (0) (0) (0) (0) (0) (0) (0) (0) (0) 21.6 Peload and Rigidity Nominal EL L M Beaing Boe Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) (N) (N/µm) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 8) ( 15) (0) ( 8) ( 14) (0) ( 8) ( 14) (0) ( 10) ( 18) (0) ( 10) ( 18) (0) ( 10) ( 17) (0) ( 10) ( 17) (0) ( 12) ( 21) (0) ( 12) ( 21) (0) ( 12) ( 21) (0) ( 12) ( 21) (0) ( 12) ( 21) (0) ( 12) ( 21) (0) ( 15) ( 26) (0) ( 15) ( 26) (0) ( 15) ( 26) (0) ( 16) ( 27) (0) ( 13) ( 23) (0) ( 15) ( 28) 552 The value in ( ) shows a measued axial cleaance. BGR02S Nominal contact angle 15 Steel ball EL Nominal Beaing Boe Peload Axial Rigidity (mm) (N) (N/µm) (0) (0) (0) (0) (0) (0) 25.3 The value in ( ) shows a measued axial cleaance. BGR02H, BGR02X Nominal contact angle 15 Ceamic ball EL Nominal Beaing Boe Peload Axial Rigidity (mm) (N) (N/µm) (0) (0) (0) (0) (0) (0)

85 4. PRELOAD AND RIGIDITY Peload and Rigidity (DB and DF Aangement) High Speed Angula Contact Thust Ball Beaings (ROBUST seies) Peload and Rigidity Double-Diection Angula Contact Thust Ball Beaings (TAC seies) Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 BAR10S Nominal contact angle 30 Steel ball BAR10H Nominal contact angle 30 Ceamic ball TAC20 seies Nominal contact angle 60 Steel ball Nominal EL L Beaing Boe Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) ( 5) ( 10) ( 5) ( 10) ( 5) ( 10) ( 5) ( 12) ( 5) ( 12) ( 5) ( 12) ( 5) ( 15) ( 5) ( 15) ( 5) ( 15) ( 5) ( 15) ( 5) ( 20) ( 5) ( 20) ( 5) ( 20) ( 5) ( 20) ( 5) ( 20) ( 5) ( 20) ( 5) ( 25) ( 5) ( 25) ( 5) ( 28) ( 5) ( 30) ( 5) ( 30) ( 5) ( 35) ( 5) ( 35) ( 5) ( 38) 860 BTR10S Nominal contact angle 40 Steel ball Nominal EL L Beaing Boe Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) ( 5) ( 10) ( 5) ( 10) ( 5) ( 10) ( 5) ( 10) ( 5) ( 10) ( 5) ( 10) ( 5) ( 15) ( 5) ( 15) ( 5) ( 15) ( 5) ( 15) ( 5) ( 20) ( 5) ( 20) ( 5) ( 20) ( 5) ( 20) ( 5) ( 20) ( 5) ( 20) ( 5) ( 25) ( 5) ( 25) ( 5) ( 25) ( 5) ( 25) ( 5) ( 30) ( 5) ( 35) ( 5) ( 35) ( 5) ( 38) The value in ( ) shows a measued axial cleaance. Nominal EL L Beaing Boe Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) ( 5) ( 10) ( 5) ( 10) ( 5) ( 10) ( 5) ( 12) ( 5) ( 12) ( 5) ( 12) ( 5) ( 15) ( 5) ( 15) ( 5) ( 15) ( 5) ( 15) ( 5) ( 20) ( 5) ( 20) ( 5) ( 20) ( 5) ( 20) ( 5) ( 20) ( 5) ( 20) ( 5) ( 25) 650 BTR10H Nominal contact angle 40 Ceamic ball Nominal EL L Beaing Boe Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) ( 5) ( 10) ( 5) ( 10) ( 5) ( 10) ( 5) ( 10) ( 5) ( 10) ( 5) ( 10) ( 5) ( 15) ( 5) ( 15) ( 5) ( 15) ( 5) ( 15) ( 5) ( 20) ( 5) ( 20) ( 5) ( 20) ( 5) ( 20) ( 5) ( 20) ( 5) ( 20) ( 5) ( 25) Nominal C6 C7 C8 Beaing Boe Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) (N) (N/µm) TAC29 seies Nominal contact angle 60 Steel ball Nominal C6 C7 C8 Beaing Boe Peload Axial Rigidity Peload Axial Rigidity Peload Axial Rigidity (mm) (N) (N/µm) (N) (N/µm) (N) (N/µm) Peload and Rigidity

86 4. PRELOAD AND RIGIDITY Peload and Rigidity Angula Contact Thust Ball Beaing fo Ball Scew Suppot Radial Intenal Cleaance of Cylindical Rolle Beaings Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 TAC B seies (fo machine tool) Nominal contact angle 60 Steel ball C9 Peload Duplex Set Aangement (DB o DF) Tiplex Set Aangement (DBD o DFD) Quaduplex Set Aangement (DBB o DFF) Beaing Numbe Peload Axial Rigidity Stating Toque Peload Axial Rigidity Stating Toque Peload Axial Rigidity Stating Toque (N) (N/µm) (N m) (N) (N/µm) (N m) (N) (N/µm) (N m) 15TAC47B TAC47B TAC47B TAC62B TAC62B TAC72B TAC72B TAC90B TAC75B TAC100B TAC100B TAC100B TAC120B TAC120B C10 Peload Duplex Set Aangement (DB o DF) Tiplex Set Aangement (DBD o DFD) Quaduplex Set Aangement (DBB o DFF) Beaing Numbe Peload Axial Rigidity Stating Toque Peload Axial Rigidity Stating Toque Peload Axial Rigidity Stating Toque (N) (N/µm) (N m) (N) (N/µm) (N m) (N) (N/µm) (N m) 15TAC47B TAC47B TAC47B TAC62B TAC62B TAC72B TAC72B TAC90B TAC75B TAC100B TAC100B TAC100B TAC120B TAC120B TAC 02, 03 seies (fo electic injection machine) Nominal contact angle Steel ball C8 Peload Duplex Set Aangement (DB o DF) Tiplex Set Aangement (DBD o DFD) Quaduplex Set Aangement (DBT o DFT) Beaing Numbe Peload Axial Rigidity Stating Toque Peload Axial Rigidity Stating Toque Peload Axial Rigidity Stating Toque (N) (N/µm) (N m) (N) (N/µm) (N m) (N) (N/µm) (N m) 15TAC02AT TAC02AT85( 1 ) TAC35-2T TAC03AT TAC03AT TAC45-2T TAC03AT TAC03AT TAC03AT TAC03AM TAC03CMC( 2 ) TAC03CMC( 2 ) ( 1 ) Value of 25TAC02AT85 is based on H peload. ( 2 ) Values of 100TAC03CMC and 120TAC03CMC ae based on EL peload. Cleaance in matched beaings with tapeed boe Nominal Beaing Boe Cleaance in Matched Beaings with Tapeed Boe (mm) CC9( 1 ) CC0 CC1 CC2 CC( 2 ) CC3 CC4 CC5 ove incl min. max. min. max. min. max. min. max. min. max. min. max. min. max. min. max ( 1 ) Applicable to cylindical olle beaings of ISO accuacy Class 4 and 5 with tapeed boes. ( 2 ) Denotes nomal cleaance fo matched cylindical olle beaings. Cleaance in matched beaings with cylindical boe Nominal Beaing Boe Cleaance in Matched Beaings with Cylindical Boe (mm) CC1 CC2 CC( 3 ) CC3 CC4 CC5 ove incl min. max. min. max. min. max. min. max. min. max. min. max ( 3 ) Denotes nomal cleaance fo matched cylindical olle beaings. Unit: µm Unit: µm Peload and Rigidity

87 5. LIMITING SPEEDS Limiting Speeds The limiting speeds listed in the Beaing Dimensional Tables ae guideline values. They ae based on a single beaing that is lightly peloaded by means of a sping and subjected to elatively light loads with good heat dissipation. The limiting speeds with gease lubication ae detemined using high quality gease in appopiate amounts. Those listed fo oil lubication ae based on the use of oil-ai (o oil mist) lubication. In situations whee the lubicating oil is used as a means to emove heat, highe speed can be achieved, howeve a lage amount of oil must be pessue fed though the beaing, so thee is a significant loss of powe. When single beaings ae used in two, thee o fou ow combinations, o the peload is inceased to impove spindle igidity, limiting speeds will be lowe than those listed. Please consult NSK fo gease lubication, as gease life must be also taken into consideation. Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Factos Influencing Limiting Speeds The limiting speed of the beaing, inside of the spindle, is affected by the following opeating conditions. 1. Lubication Method The thickness of the lubicating film ceated by the oil-ai o oil mist lubication eplenishment method is lage compaed to the thickness ceated by the gease lubication method. Theefoe the limiting speed is highe when the oil-ai o oil mist lubication method is used. In the case of jet lubication, the lage volume of oil supplied into the beaing fo lubication also emoves heat efficiently so that much highe opeating speeds ae possible. Speed Factos The limiting speed of a matched beaing set opeating unde position peload conditions is calculated by multiplying the limiting speed of a single beaing in the set by the appopiate adjustment facto listed in Table 5.1. In this table, peloads mean the peload values afte the beaing has been attached to the spindle. Peload values afte the beaing has been mounted on the spindle will change as a esult of the shaft fit equiements of high speed opeation and space defomation due to tightening foce. In such case, paticula in high speed applications, it is necessay to adjust the space lengths elative to each othe in ode to compensate fo the changes in peload afte beaing mounting. Table 5.1 Speed Factos Aangement EL L M H DB DBB DBD Combination If beaings ae used as multiple beaing sets, the numbe of beaings in the set affects the limiting speed. As the numbe is inceased, the limiting speed becomes lowe because the ability to dissipate that heat becomes lowe. 3. Peload If the peload afte mounted is high, the contact suface pessue between the olling elements and aceways inceases, which causes exta heat. As a esult of this heat, the peload duing opeation inceases futhe and the isk of beaing failue will be highe. To avoid this type of beaing failue, the limiting speed is educed. Also in case of cylindical olle beaings, when the adial cleaance is educed and the peload inceases duing opeation, the limiting speed is educed. 4. Dive Method The limiting speed of a beaing will also change depending on the spindle dive system. In the case of moto built-in spindles the heat inside of the spindles is highe. If thee is also a jacket-cooling system, the tempeatue diffeence between the inne ing and the oute ing becomes highe, so the peload is inceased and the limiting speed becomes lowe (see Fig. 5.2). Jacket cooling also affects the cleaance between the beaing and the housing (see Fig. 5.3). Theefoe, the cleaance between the beaing and the housing could become negative, in which case the peload would be inceased. Limiting Speeds Factos that Change Peload Fig. 5.1 Peload Setting Study Flow Peload incease due to defomation of inne ing space caused by nut tightening foce Peload incease due to centifugal foce on balls Peload incease due to inne/oute ing tempeatue diffeence Peload change due to heat expansion of balls Fig. 5.2 The Influence of the Jacket Cooling on Limiting Speed Fig. 5.3 The Influence of the Cleaance between the Beaing & the Housing on Limiting Speed Initial peload o axial cleaance Peload incease due to intefeence fits between inne ing and shaft Defomation of oute ing space due to compession by etaining cove (Decease of Peload) Peload afte mounted necessay peload foce fo cutting in low speed Taget K A 100 N/ µ m (K A: Axial igidity) Expansion of inne ing aceway due to centifugal foce (Incease of Peload) Decease of intefeence fits by expansion of inne ing and shaft due to centifugal foce (Decease of Peload) Pope peload to ensue high speed opeation Stability in high speed P V Citeia P : Contact pessue between balls and aceway V : Gyo slip + Spin slip velocity Fatigue Life Oute ing tempeatue ise, C BNR10XTDB 45 Peload afte mounted: 250 N 40 Lubication: oil-ai Without jacket cooling, Inne ing Without jacket cooling, Oute ing 25 3 C, 21/min, Inne ing 3 C, 21/min, Oute ing C, 51/min, Inne ing 0 C, 51/min, Oute ing Speed, min 1 Oute ing tempeatue ise, C BNR10XTDB Peload ofte mounted: 150 N Lubication: oil-ai Jacket cooling: +3 C, 21/min Loose amount on housing: 21 µm Loose amount on housing: 7 µm Abnomal tempeatue ise Abnomal tempeatue ise Speed, min

88 LUBRICATION Puposes of Lubication The main puposes of lubication ae to educe fiction and wea inside the beaing that may cause pematue failue. The effects of lubication may be biefly explained as follows: (1) Reduction of Fiction and Wea Diect metallic contact between the beaing ings, olling elements, and cage, which ae the basic pats of a beaing, is pevented by an oil film which educes the fiction and wea in the contact aeas. (2) Extension of Fatigue Life The olling fatigue life of beaings depends geatly upon the viscosity and film thickness between the olling contact sufaces. A heavy film thickness polongs the fatigue life, but it is shotened if the viscosity of the oil is too low so the film thickness is insufficient. (3) Dissipation of Heat Ciculating lubication may be used to cay away fictional heat o heat tansfeed fom the outside to pevent the beaing fom oveheating and oil fom deteioating. (4) Othes Adequate lubication also helps to pevent foeign mateial fom enteing the beaings and guads against coosion o usting. Lubicating Methods Fo machine tool spindles in which high accuacy is impotant, it is necessay to pevent excessive tempeatue ise of the spindle to educe themal defomation. Beaing heat geneation is divided into a load tem detemined by the beaing type and load, and a speed tem detemined by the lubicating method and speed. Geneally, the speed tem is geate, but if a lubicating method esulting in a small speed tem is selected, the influence of the load tem cannot be disegaded. Theefoe, it is impotant to select a low heat geneating beaing (load tem) and lubicating method (speed tem). Regading heat geneation, both the lubication method and quantity of lubicant have impotant effects. Lubication using a small amount of gease is common since this method is economical, maintenance fee, and thee is little heat geneation. At high speeds, to maintain a constant low tempeatue, the oil-ai lubication method, which equies a minimum quantity of oil, was developed. The elation between oil quantity and heat geneation (fictional loss) and tempeatue ise is aleady known as shown in Fig Theefoe, fo machine tool spindles, to avoid excessive tempeatue ise, adoption of a lubicating method aiming at eithe zone A o B is necessay. The lubicating methods in zones A and B ae summaized in Table 6.1. Dynamic toque of beaing (heat geneation) M=Ml+Mv Heat Geneation Tempeatue Rise Tempeatue ise Seizue Load tem (Detemined by beaing type and load) Ml=f 1Fd m whee f1 : Coefficient detemined by beaing type and load F : Load dm : Pitch cicle diamete of olling element Speed tem (Detemined by oil viscosity, amount, speed) Mv=f 0 ( ν 0 n) 2/3 dm 3 whee f0 : Coefficient detemined by beaing and lubicating method ν0 : Kinematic viscosity of oil n : Speed Fig. 6.1 Oil Quantity and Tempeatue Rise Amount of heat geneation Zone A Oil-ai lubication Oil mist lubication Gease lubication Zone B Foced ciculation lubication Jet lubication Oil Quantity Table 6.1 Compaison of Lubicating Methods Lubicating Methods Gease Lubication Oil Mist Lubication Jet Lubication Oil-Ai Lubication Gease Lubication (1) Recommended Geases Lithium base geases with mineal oil as the base oil have good sticking popeties and excellent chaacteistics fo olling beaings. These ae usually usable ove a tempeatue ange of 10 C to +110 C. As gease fo high speed machine tool spindles that equie low tempeatue ise and long life, a consistency No.2 gease with a synthetic base oil (dieste, dieste + mineal oil, etc.) is ecommended. Table 6.2 lists the band names and popeties of geases widely used in machine tools main spindles and ball scew suppot beaings. (2) Gease Life Gease life depends geatly upon opeating tempeatue; theefoe, it is necessay to keep the tempeatue of the beaing (including atmospheic tempeatue) coole, in ode to extend the gease life. High pefomance wide ange gease is often used fo high Table 6.2 Gease Band Names and Popeties Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Advantages Cost is low. Limitation of tempeatue ise is possible. Maintenance fee. Since new oil is always fed, no fea of oil deteioation. Dust and cutting fluid cannot easily ente. Since the oil flow ate is high, dust and cutting fluid cannot ente and seizue hadly eve occus. Because of cooling by oil, the beaing tempeatue can be contolled to some degee. Since oil quantity contol is possible, the optimum quantity of oil is fed and heat geneation is low. Besides little heat-geneation, thee is a cooling effect of the ai, so the tempeatue is low. Since new oil is always fed, no fea of oil deteioation. Dust, cutting fluid cannot easily ente. Envionmental pollution mist is slight. Base oils Dopping Woking Band names Manufactues Thickenes Base oils viscosity point tempeatue Main application mm 2 s(40 C) ( C) ange, ( C) MTE NSK Baium complex Este oil to +120 Beaings fo high speed spindles, high speed cylindical olle beaings MTS NSK Uea Este+Synthetic hydo cabon oil to +130 Beaings fo high speed spindles Isoflex NBU15 Klübe Baium complex Dieste oil + Mineal oil to +120 Beaings fo main spindles Multemps PS No.2 Kyodo Yushi Lithium Dieste oil + Mineal oil to +110 Beaings fo main spindles Mobilux 2 Mobil Lithium Mineal oil to +110 Beaings fo boing heads, live centes Multemp LRL3 Kyodo Yushi Lithium Polyol este oil to +130 Beaings fo main spindles Stabagus NBU8EP Klübe Baium complex Mineal oil to +130 Disadvantages If packed gease deteioates, seizue may occu. May allow penetation of dust o cutting fluid. Pollution of envionment. Oil supply quantity vaies depending on the oil viscosity and tempeatue, so contol of a small flow ate is difficult. It is difficult to confim that oil is actually fed. Fictional loss is high. Since oil leaks, it is difficult to use fo vetical spindles. Cost is high. Cost is athe high. Confimation of whethe oil is actually fed to beaing is difficult. speed spindle beaings, o spindle moto beaings. The following equation shows the mean life of wide ange gease: log t= n/nmax ( n/Nmax) T whee t : Mean Gease life (h) Nmax : Limiting speed (min 1 ) n : Opeating speed (min 1 ) T : Beaing unning tempeatue ( C) (3) Quantity of Gease fo High Speed Spindle Beaings To opeate beaings at high speed with gease lubication, the ecommended quantity to be packed is 10% to 20% of intenal space. If too much gease is packed, duing unning in, abnomal heat geneation occus and this may cause the gease to deteioate. To avoid such a isk, it is necessay to un in spindles fo a sufficient time. Based on thei expeience, NSK detemines the packing quantity which allows easy unning in and will povide sufficient lubication. Fo the amount, please efe to the tables on Page 175. Heavy load cylindical olle beaings Alvania 2 Shell Lithium Mineal oil to +110 Ball scew suppot beaings ENS NSK Uea Polyol este oil to +160 Beaings fo motos WPH NSK Diuea Poly-α-olefin oil to +150 Ball scew suppot beaings Lubication 173

89 LUBRICATION Oil Lubication (1) Oil Mist Lubication and Oil-Ai Lubication (Minimal Oil Quantity Lubication) Spay oiling is a method of spaying oil by tuning it into a mist using compessed ai. It is also called oil mist lubication. Oil-ai lubication is a method of feeding oil continuously by injecting oil into a compessed ai steam by means of a mixing valve that intemittently dischages the minimum quantity of oil using a constant-quantity piston. Fig. 6.2 shows the ecommended oil quantity fo the lubication methods descibed above, each quantity is fo one beaing. In case of oil mist lubication, it s necessay to adjust the oil quantity to accommodate fo the effects of the banches in path tubing, and leakage fom the gaps aound the spaces. Please ask NSK, as the oil quantity should be inceased, in cases whee the d m n value is highe than Fo the position of the spay nozzle, please efe to Page 192. (2) Jet Lubication Jet lubication is mainly used fo high speed beaings with a d m n value Though one to seveal nozzles, jets of lubicating oil unde a constant pessue pass though the beaings. At high speed, the ai suounding the beaing otates togethe with the beaing and foms an ai wall. The speed of the jet fom each nozzle must be faste by 20% than the cicumfeential speed of the inne ing outside suface. Since the jet lubication uses a lage quantity of oil, thee is much agitation esistance, so it is necessay to dissipate the heat effectively using a lage oil dischage outlet and foced dischage. Fo machine tool spindle beaings, this method is used in some applications as a means fo stable opeation at ulta high speeds (see Fig. 6.3). Fo the position of the spay nozzle, please efe to page 192. Fig. 6.3 Spindle Stuctue with Jet Lubication Ai seal Fig. 6.2 Recommended Oil Quantity fo Each Boe Size of Beaing (Minimal Oil Quantity Lubication) Oil quantity, cc/h Additional oil outlet 0.03 cc/16 min. Oil inlet Main oil outlet Angula contact ball beaing 1.2d cc/8 min. Ai seal Cylindical olle beaing 0.4d cc/16 min Beaing boe, mm 0.01 cc/8 min. Boe numbe Boe diamete (mm) Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 The Recommended Gease Quantities fo High-speed Spindle Beaings Unit: cc/beaing Angula contact ball beaing : 15% of intenal space Cylindical olle beaing : 10% of intenal space BNR19 BNR10 BGR19 BGR10 BGR02 BAR10 NN49 NN39 NN30 N10 79xx 70xx 72xx BTR10 X-quantity X-quantity X-quantity X-quantity X-quantity X-quantity X-quantity X-quantity The gease quantity of xxtac20(29)x(d) should be same as the double ow cylindical olle beaing s, which is assembled with this beaing togethe. Use the gease listed on Page 173, and multiply 0.93 (density) to the quantity above, fo the weight of the gease. Fo the ecomended gease quantity fo angula contact thust ball beaing fo ball scew suppot, please efe to Page Lubication 175

90 BEARING TOLERANCES The toleance fo the bounday dimensions and unning accuacy of NSK adial beaings ae specified by the Accuacies of Rolling Beaings in ISO 492/199/582/1132-1, and Rolling Beaing Toleances in JIS B In addition to the above toleances, NSK manufactues angula contact ball beaings with pecision classes ABEC 5, 7, and 9 as specified by Ameican Beaing Manufactues Association (ABMA) Standad 20. Rough definitions of the items listed fo unning accuacy and thei measuing methods ae descibed in Fig. 7.1 and Table 7.1. Futhe details ae available in ISO 5593, Rolling Beaings Vocabulay in JIS B 0104, and Measuing Methods fo Rolling Beaings in JIS B Table 7.1 Running Accuacy Inne Ring Oute Ring Dial Gauge Radial unout of assembled beaing inne ing K ia Rotating Stationay A Radial unout of assembled beaing oute ing K ea Stationay Rotating A Assembled beaing inne ing face (backface) unout with aceway S ia Rotating Stationay B 1 Assembled beaing oute ing face (backface) unout with aceway S ea Stationay Rotating B 2 Inne ing efeence face (backface, whee applicable) unout with aceway S d Rotating Stationay C Vaiation of beaing outside suface geneatix inclination with oute ing efeence face (backface) S D N/A Rotating D Toleance fo Radial Beaings Inne Ring Table 7.2 Inne Ring (Class 5) Nominal Boe Diamete Single Plane Mean d Boe Dia. Deviation (mm) dmp( 2 ) ( 1 ) Applicable to individual ings manufactued fo combined beaings. ( 2 ) Applicable to beaings with cylindical boes. ( 3 ) Class 3 is NSK s oiginal accuacy. Toleance of beaing boe diamete and oute ing diamete ae Class 4. Othe toleances ae Class 2. ( 4 ) Applicable to ball beaings. Remaks: Boe Dia. Vaiation in a Single Radial Plane Mean Boe Dia. Radial Runout Inne Ring Run Inne Ring Deviation of Single Inne Ring Width V dp ( 2 ) Face Runout Bs Inne Ring Vaiation of Inne Ring out with Boe Diamete Seies with Raceway Single Beaing ( V dmp ( 2 ) K ia S 1 ) Width Vaiation 9 0, 2, 3 d S ia( 4 ) Combined Beaing Single Beaing Combined Beaing V Bs ove incl high low max. max. max. max. max. high low max Table 7.3 Inne Ring (Class 4) Nominal Boe Diamete Single plane mean Deviation of a d boe dia. deviation Single Boe Dia. (mm) dmp( 2 ) ds( 2 ) Boe dia. Vaiation in a Single Mean Boe Dia. Radial Runout Inne Ring Inne Ring Deviation of Single inne Ring Width Radial Plane V dp ( 2 ) Face Runout Bs Inne Ring Vaiation of Inne Ring Runout with boe Diamete Seies with Raceway Single Beaing ( V dmp ( 2 ) K ia S 1 ) Width Vaiation 9 0, 2, 3 d S ia( 4 ) Combined Beaing Single Beaing Combined Beaing V Bs ove incl high low high low max. max. max. max. max. high low max The cylindical boe diamete toleance limit (high), as pe the no-go side of a plug gauge as specified in this table, is not necessaily applicable within a distance of 1.2 times the chamfe dimension (max.) fom the ing face. 2. ABMA Standads ABEC5, ABEC7, and ABEC9 ae equivalent to ISO (JIS) Classes 5, 4, and 2 espectively. ABMA Standads ae applicable to angula contact ball beaings. Unit: µm Unit: µm Fig. 7.1 Measuing Methods fo Running Accuacy Measuing weight B1 Table 7.4 Inne Ring (Class 3) ( 3 ) Inne ing (Class 4Y) (As fo Class 4Y (P4Y), boe diamete dimensional accuacy and outside diamete dimensional accuacy ae special.) Table 7.6 Toleance of Boe Diamete of Inne Ring Unit: µm Boe diamete (mm) Class 4 Class 4Y (Contolled to medium value) ove incl high low high low C Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 B2 Measuing weight A (max) 1.2 D (max) 1.2 Stop (at two points) Nominal Boe Diamete Single Plane Mean Boe Dia. Vaiation Mean Boe Dia. Radial Runout Inne Ring Runout Inne Ring Deviation of Single Inne Ring Width Inne Ring Width d Boe Dia. Deviation Deviation of a Single Boe Dia. in a Single Face Runout Bs Vaiation of Inne Ring with Boe Vaiation (mm) dmp( 2 ) ds( 2 ) Radial Plane with Raceway V dmp ( 2 ) K ia S Single Beaing ( 1 ) d V V dp( 2 ) S ia( 4 ) Bs Combined Beaing Single Beaing Combined Beaing ove incl high low high low max. max. max. max. max. high low max Toleances fo beaings unde 30 mm boe ae the same as values quoted fo beaings with boes between mm. Class 4Y is NSK s popietay accuacy standad, in which toleance of a beaing boe diamete and an oute ing diamete ae in a special class (contolled to medium value) and othe toleances ae Class 4. Class 4Y has the same unning accuacy as Class 4 but has a naowe toleance ange of boe and oute diamete than Class 4. It is suitable fo univesal combination beaings. A C Unit: µm Table 7.5 Inne Ring (Class 2) Unit: µm Nominal Boe Diamete Single Plane Mean Boe Dia. Vaiation Mean Boe Dia. Radial Runout Inne Ring Runout Inne Ring Deviation of Single Inne Ring Width Inne Ring Width d Boe Dia. Deviation Deviation of a Single Boe Dia. in a Single Face Runout Bs Vaiation of Inne Ring with Boe Vaiation (mm) dmp( 2 ) ds( 2 ) Radial Plane with Raceway V dmp ( 2 ) K ia S Single Beaing ( 1 ) d V V dp( 2 ) S ia( 4 ) Bs Combined Beaing Single Beaing Combined Beaing ove incl high low high low max. max. max. max. max. high low max Beaing Toleances 177

91 7. BEARING TOLERANCES Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Toleance fo Radial Beaings Oute Ring Table 7.6 Oute Ring (Class 5) Nominal Outside Diamete D (mm) Single Plane Mean Outside Dia. Deviation Dmp Unit: µm Outside Dia. Vaiation in a Single Radial Plane Vaiation of Outside V Mean Outside Radial Runout Oute Ring Face Deviation of Single Oute Ring Dp Suface Geneatix Dia. Vaiation of Oute Ring Diamete Seies Inclination with Face Runout with Raceway Oute Ring Width Width Vaiation V 9 0, 2 Dmp K ea S S ea ( 1 ) Cs V Cs D ove incl high low max. max. max. max. max. max Equal to the value of inne ing ( Bs) of the same beaing numbe Table 7.7 Oute Ring (Class 4) Unit: µm Outside Dia. Vaiation in a Single Radial Plane Vaiation of Outside Nominal Outside Diamete Single Plane Mean Deviation of Single V Mean Outside Radial Runout Oute Ring Face Deviation of Single Oute Ring Dp Suface Geneatix D Outside Dia. Deviation Outside Dia. Dia. Vaiation of Oute Ring Diamete Seies Inclination with Face Runout with Raceway Oute Ring Width Width Vaiation (mm) Dmp DS V 9 0, 2 Dmp K ea S S ea ( 1 ) Cs V Cs D ove incl high low high low max. max. max. max. max. max Equal to the value of inne ing ( Bs) of the same beaing numbe ( 1 ) Applicable to ball beaings. ( 2 ) Class 3 is NSK s oiginal accuacy. Toleance of beaing boe diamete and oute ing diamete ae Class 4. Othe toleances ae Class 2. Remaks: 1. The cylindical boe diamete toleance limit (high), as pe the no-go side of a plug gauge as specified in this table, is not necessaily applicable within a distance of 1.2 times the chamfe dimension (max.) fom the ing face. 2. ABMA Standads ABEC5, ABEC7, and ABEC9 ae equivalent to ISO (JIS) Classes 5, 4, and 2 espectively. ABMA Standads ae applicable to angula contact ball beaings. Table 7.8 Oute Ring (Class 3)( 2 ) Nominal Outside Diamete Single Plane Mean Deviation of Single Outside Dia. Vaiation Mean Outside Radial Runout Vaiation of Outside Oute Ring Face Deviation of Single Oute Ring Suface Geneatix D Outside Dia. Deviation Outside Dia. in a Single Radial Plane Dia. Vaiation of Oute Ring Runout with Raceway Oute Ring Width Width Vaiation Inclination with Face (mm) Dmp Ds V Dp V Dmp K ea S ea ( 1 ) Cs V Cs ove incl high low high low max. max. max. max. max. max Equal to the value of inne ing ( Bs) of the same beaing numbe Table 7.9 Oute Ring (Class 2) Nominal Outside Diamete Single Plane Mean Deviation of Single Outside Dia. Vaiation Mean Outside Radial Runout Vaiation of Outside Oute Ring Face Deviation of Single Oute Ring Suface Geneatix D Outside Dia. Deviation Outside Dia. in a Single Radial Plane Dia. Vaiation of Oute Ring Runout with Raceway Oute Ring Width Width Vaiation Inclination with Face (mm) Dmp Ds V Dp V Dmp K ea S ea ( 1 ) Cs V Cs ove incl high low high low max. max. max. max. max. max Equal to the value of inne ing ( Bs) of the same beaing numbe Oute ing (Class 4Y) Table 7.11 Toleance of Oute Diamete of Oute Ring Unit: µm Oute diamete (mm) Class 4 Class 4Y (Contolled to medium value) ove incl high low high low and less Toleances fo beaings unde 50 mm oute diamete ae the same as values quoted fo beaings with oute diametes between mm. Class 4Y is NSK s popietay accuacy standad in which toleance of a beaing boe diamete and an oute ing diamete ae in a special class (contolled to medium value) and othe toleances ae Class 4. Class 4Y has the same unning accuacy as Class 4 but has a naowe toleance ange of boe and oute diamete than Class 4. It is suitable fo univesal combination beaings. S D S D Unit: µm Unit: µm Beaing Toleances

92 7. BEARING TOLERANCES Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Toleances fo Tapeed Boes of Cylindical Rolle Beaings Toleances fo Tapeed Boes The boe accuacy of tapeed boe cylindical olle beaings is specified by ISO. Howeve, in this standad, the toleances ae athe wide. Fo pecision-class cylindical olle beaings, NSK established its own naowe toleances. As is customay, howeve, two tape angles ae available within the toleance ange specified by ISO (see Fig. 7.2). (NSK teminated poduction of K tapeed boe cylindical olle beaings and is poducing only KR tapeed boe cylindical olle beaings.) Fig. 7.2 Toleances KR K Tape 1:12 ( ) Toleances confom to ISO KR : NSK s oiginal toleance fo tapeed boes has a vey naow ange that is positioned towads the lowe limit of the standad ISO ange. This NSK toleance is naowe than that of ISO, which enhances easie mounting. Table 7.10 KR Tapeed Boes Unit: µm d (Refeence) ( 2 ) dmp (mm) d1mp dmp ove incl high low high low max ( 1 ) Boe diamete vaiation in a single adial plane, which is applicable to all adial planes of tapeed boes. ( 2 ) Tape angula toleance, d (mm) Table 7.11 K Tapeed Boes Unit: µm V dp ( 1 ) dmp d1mp dmp V dp ( 1 ) Fig. 7.3 Tapeed Boe Toleances Nominal tapeed boe OK : NSK s oiginal toleance fo tapeed boe has a vey naow ange that is positioned midange of the ISO standad. Boe dimensional toleances ae identical to those of ISO. Tapeed boe with a single plane mean boe diamete deviation fom basic boe diamete ove incl high low high low max ( 1 ) Boe diamete vaiation in an single adial plane, which is applicable to all adial planes of tapeed boes. d1mp dmp 2 d α Tape 1:12 d1 (d + dmp) α (d 1 + d1mp) Beaing Toleances B B d : Nominal boe diamete d 1 : Theoetical lage boe end of tapeed boe d 1 =d+ B dmp : Single plane mean boe diamete deviation in the theoetical small boe end of the boe d1mp : 1 12 Single plane mean boe diamete deviation in the theoetical lage boe end of the boe B: Nominal inne ing width α : Half of tape angle of tapeed boe α= = = ad

93 7. BEARING TOLERANCES Toleances fo Angula Contact Thust Ball Beaings Toleances fo high speed angula contact thust ball beaing (Class 4A( 1 ) of BAR and BTR types) Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Toleances fo Angula Contact Ball Beaing fo Ball Scew Suppot Machine Tool Applications Table 7.14 Inne ing Unit: µm Nominal Boe Single Plane Deviation of a Boe Dia. Vaiation in Mean Boe Radial Inne Ring Inne Ring Inne Ring Deviation of Diamete Mean Boe Single Boe Dia. a Single Radial Plane Dia. Runout of Runout Face Runout Width Single Inne Dia. Deviation V dp Vaiation Inne Ring with Boe with Raceway Vaiation Ring Width d dmp ds Diamete Seies V dmp K ia S d S ia V Bs Bs ( Cs) (mm) 9 0 ove incl high low high low max. max. max. max. max. max. max. high low Table 7.18 TAC B seies Unit: µm Deviation of Inne Inne o Oute Ring Deviation of Boe Diamete Deviation of Outside Diamete Nominal Boe o Ring Width Runout with Raceway Outside Diametes Toleance Classes Toleance Classes Toleance Classes Toleance Classes (mm) PN7A PN7A PN7A PN7B PN7A PN7B PN7B PN7B ove incl high low high low high low high low high low max Remak: Vaiation of oute ing width is the same as that fo the inne ing of the same beaing. Class PN7A is the standad toleance fo these beaings. This coesponds to ISO Class 4 fo adial ball beaings, but fo the unout of the inne and oute ings, moe stingent values ae applied. Table 7.15 Oute ing Unit: µm Nominal Outside Single Plane Deviation of Outside Dia. Vaiation Mean Outside Radial Vaiation of Outside Oute Ring Oute Ring Diamete Mean Outside Single Outside Dia. in a Single Radial Plane Dia. Vaiation Runout of Suface Geneatix Face Runout Width Dia. Deviation V Dp Oute Ring Inclination with Face with Raceway Vaiation D Dmp Ds Diamete Seies V Dmp K ea S D S ea V Cs (mm) 9 0 ove incl high low high low max. max. max. max. max. max. max ( 1 ) NSK specification. Equivalent to ISO Class 4 except fo toleance of oute ing outside diamete. Toleances fo double diection angula contact thust ball beaing (Class 7( 2 ) of TAC type) Table 7.16 Toleances of inne ing, oute ing, and beaing height Unit: µm Nominal Boe Deviation of a Single Deviation of the Radial Runout of Assembled Inne Ring Inne ing (Oute Ring) Diamete Boe Diamete Actual Beaing Height Beaing Inne Ring (Oute Ring) Runout Face Runout with Raceway d ds Ts K ia with Boe S ia (mm) (K ea ) S d (S ea ) ove incl high low high low max. max. max ( 2 ) NSK specification Table 7.17 Toleance of oute ing Unit: µm Nominal Outside Deviation of Diamete Single Outside Dia. D Ds (mm) ove incl high low The sticte Class PN7B applies to the dimensional toleances of the boes and outside diametes of single-ow univesal aangement beaings (SU). Electical Injection Molding Machine Table 7.19 TAC 02 and 03 seies Unit: µm Inne o Oute Ring Nominal Boe o Deviation of Boe Diamete Deviation of Outside Diamete Deviation of Inne Ring Width Runout with Raceway Outside Diamete Toleance Class (mm) PN5D ove incl high low high low high low max Remak: Vaiation of oute ing width is the same as that fo the inne ing of the same beaing. Class PN5D is the standad toleance fo these beaings. This coesponds to ISO Class 5 fo adial ball beaings, but fo the unout of the inne and oute ings, moe stingent values ae applied. Beaing Toleances

94 8. DESIGN OF SHAFTS AND HOUSINGS Fitting of Shafts and Housings It is of utmost impotance that shafts and housings ae accuately and pecisely mated in ode to take full advantage of the pecision beaings capabilities, which include otational accuacy, high speed pefomance, and low heat geneation. When the inne ing o oute ing is mounted onto a shaft o into a housing with some intefeence, the shape of shaft o housing (out of oundness) is tansfeed to the beaing aceway sufaces and affects unning accuacy. When multiple angula contact ball beaings ae used, cylindicality affects the distibution of peload fo each beaing. Theefoe, the mating pats should be as accuate as possible. Inaccuate mating of pats can cause the fomation of peaks o idges along the shaft of a pecision lathe, which can affect the quality of finished wok. Table 8.1 Fits on Shafts ( 1 ) Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 If the tape of the inne ing fo a double ow cylindical olle beaing with a tapeed boe does not match that of the shaft, the esidual cleaance will be diffeent fo two of the ows. Theefoe, load will not be sustained nomally, and will impai igidity o cause iegula movement of the olles due to tape of the inne ing goove. We ecommend that you gauge the tapeed pats to be mated with beaings. Contact should cove moe than 80% of the total suface aea that is dyed blue. The ecommended accuacy and suface oughness of beaing mounting seats ae shown in following tables: Table 8.3 Toleance fo and Mean Roughness of Shafts a b d A 184 Beaing Type Shaft Oute Diamete (mm) Toleance of Shaft ( 2 ) Oute Diamete (mm) Taget Intefeence ( 2 ) ( 4 ) (mm) ove incl min. max. min. max T T Machine tool T spindle beaing ( 3 ) T T T Angula contact thust ball beaing fo ball scew suppot Table 8.2 Fits on Housings ( 1 ) Beaing Type Housing Boe Diamete (mm) Toleance of Housing ( 2 ) Boe Diamete (mm) Taget Cleaance ( 2 ) ( 4 ) (mm) ove incl min. max. min. max L 0.006L L 0.006L Angula contact ball L 0.008L beaing (Fixed end) L 0.008L L 0.010L L 0.011L L 0.011L Angula contact ball L 0.015L beaing (Fee end) L 0.015L L 0.022L L 0.002T L 0.002T Cylindical olle L 0.002T beaing L 0.002T L 0.002T Angula contact thust ball beaing fo ball scew suppot Toleance Gades and Mean Roughness (µm) Shaft Diamete Out-of-oundness ( ) Cylindicity ( ) Runout ( ) Coaxiality ( ) Roughness (mm) a b c d R a Beaing Accuacy Beaing Accuacy Beaing Accuacy Beaing Accuacy Beaing Accuacy ove incl P5, P4 P3, P2 P5, P4 P3, P2 P5, P4 P3, P2 P5, P4 P3, P2 P5, P4 P3, P Table 8.4 Toleance fo and Mean Roughness of Housings Toleance Gades and Mean Roughness (µm) ( 1 ) The fitting data above povides geneal ecommendations fo machine tool spindles opeating unde nomal conditions and fo d m n values of less than Housing Boe Diamete Out-of-oundness ( ) Cylindicity ( ) Runout ( ) Coaxiality ( ) Roughness 800,000. Fo high speeds, heavy loads, o oute ing otation, please contact NSK fo assistance. (mm) a 1 b 1 c 1 d 1 R a ( 2 ) Use the taget intefeence when the beaing can be matched to the shaft o housing, Othewise, use the shaft oute diamete and housing boe Beaing Accuacy Beaing Accuacy Beaing Accuacy Beaing Accuacy Beaing Accuacy minimum and maximum fo andom matching. ove incl P5, P4 P3, P2 P5, P4 P3, P2 P5, P4 P3, P2 P5, P4 P3, P2 P5, P4 P3, P ( 3 ) Applies to angula contact ball beaings: 70XX, 79XX, 72XX, BNR and BER Angula contact thust ball beaings: BAR, BTR and TAC Cylindical olles beaings: N10XX, NN30XX, NN39XX, NN49XX and NNU49XX ( 4 ) T=Intefeence o tight fit L=Cleaance o loose fit c 1 AB A A C AB a 1 b 1 d 1 B A B c 1 AB Design of Shafts and Housings 185

95 8. DESIGN OF SHAFTS AND HOUSINGS Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Shoulde and Fillet Dimensions Table 8.5 Shoulde and Fillet Dimensions fo Angula Contact Ball Beaings Unit: mm Table 8.6 Shoulde and Fillet Dimension fo Cylindical Rolle Beaings Unit: mm Dimension Seies 19 Dimension Seies 10 Dimension Seies 02 Nominal 79XX, BNR19, BER19, BAR19, 70XX, BNR10, BER10, BAR10, 72XX, BGR02 Boe BTR19, BGR19, TAC29X BTR10, BGR10, TAC20X Diamete d a D a D b a b d a D a D b a b d a D a D b a b (min.) (max.) (max.) (max.) (max.) (min.) (max.) (max.) (max.) (max.) (min.) (max.) (max.) (max.) (max.) Dimension Seies 19 Dimension Seies 10 (Double ow) Dimension Seies 10 (Single ow) Nominal NN39, NN49, NNU49 NN30XX N10XX Boe d a d 1a d c D a a d a d 1a D a a d a d 1a D a Diamete a (min.) (min.) (min.) (max.) (min.) (max.) (min.) (min.) (max.) (min.) (max.) (min.) (min.) (max.) (min.) (max.) Fig. 8.1 Figue of Shoulde and Fillet Dimension a a b a Da da Db da a a Design of Shafts and Housings a a Da da a d1a dc da d1a Da da d1a Da

96 8. DESIGN OF SHAFTS AND HOUSINGS 9. SPACERS Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Chamfe Dimension Limits and Cone Radius of Shaft o Housing Fig. 8.2 Chamfe Dimension Space Dimensions The dimensions of standad spaces fo angula contact ball beaings (19, 29, 10, 20 and 02 seies) ae listed below: (max.) o 1 (max.) (Radial diection) (min.) o 1 (min.) (max.) o 1 (max.) Spaces Side face o inne/oute ing (Axial diection) (min.) o 1 (min.) (min.) o 1 (min.) Beaing Boe suface o outside suface : chamfe dimension of inne/oute ing 1: chamfe dimension of inne/oute ing (Font side) Remaks: The pecise shape of chamfe sufaces has not been specified but its pofile in the axial plane shall not intesect an ac of adius (min.) o 1 (min.) touching the side face of an inne ing and boe suface, o the side face of an oute ing and outside suface. Table 8.7 Chamfe Dimension Limits Unit: mm Unit: mm Pemissible Pemissible Refeence Pemissible Pemissible Refeence Chamfe Nominal Boe Diamete Chamfe Dimension fo Cone Radius of Chamfe Nominal Boe Diamete Chamfe Dimension fo Cone Radius of Dimension d Inne/Oute Rings Dimension Shaft o fo Inne/Oute d Inne/Oute Rings Shaft o fo Inne/Oute Rings (min.) (max.) o 1 (max.) Housing a Rings (min.) (max.) o 1 (max.) Housing a o 1 (min.) ove incl Radial Diection Axial Diection ( 1 ) max. o 1 (min.) ove incl Radial Diection Axial Diection ( 1 ) max ( 1 ) Fo beaings with nominal widths less than 2 mm, the value of (max) in the axial diection is the same as that in the adial diection. Additional infomation: Mateial of space: Steel (SUJ2) o S C steel When using spaces, paallelism of space end sufaces should be less than mm. 19 o 29 Seies Standad Spaces fo Dimension Seies 19 o 29 (79, BNR19, BER19, BNR29, BER29, BGR19) Boe Numbes Nominal Boe Diamete Oute Diamete Oute Ring Space Inne Ring Space Oute Diamete ( 1 ) Boe Oute Diamete Boe ( 2 ) Space Chamfe Unit: mm ( 1 ) Fo oute ing spaces opeating unde oil mist lubication o jet lubication, the oute diamete of the oute ing space is the same as that of the beaing outside diamete. Recommend maintaining a toleance of g5 o bette. ( 2 ) Fo high speed opeations exceeding a value of d m n , the boe diamete of the inne ing space is the same as that of the beaing boe. Recommend maintaining a toleance of F6 o bette

97 9. SPACERS Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Additional infomation: Mateial of space: Steel (SUJ2) o S C steel When using spaces, paallelism of space end sufaces should be less than mm. 10 o 20 Seies Standad spaces fo dimension seies 10 o 20 (70, BNR10, BER10, BNR20, BER20, BGR10) Unit: mm 02 Seies Standad spaces fo dimension seies 02 (72, BGR02) Boe Numbes Nominal Boe Diamete Oute Diamete Oute Ring Space Inne Ring Space Oute Diamete ( 1 ) Boe Oute Diamete Boe ( 2 ) Space Chamfe ( 1 ) Fo oute ing spaces opeating unde oil mist lubication o jet lubication, the oute diamete of the oute ing space is the same as that of the beaing outside diamete. Recommend maintaining a toleance of g5 o bette. ( 2 ) Fo high speed opeations exceeding a value of d m n , the boe diamete of the inne ing space is the same as that of the beaing boe. Recommend maintaining a toleance of F6 o bette. Boe Numbes Nominal Boe Diamete Oute Diamete Oute Ring Space Inne Ring Space Oute Diamete ( 1 ) Boe Oute Diamete Boe ( 2 ) Space Chamfe Unit: mm ( 1 ) Fo oute ing spaces opeating unde oil mist lubication o jet lubication, the oute diamete of the oute ing space is the same as that of the beaing outside diamete. Recommend maintaining a toleance of g5 o bette. ( 2 ) Fo high speed opeations exceeding a value of d m n , the boe diamete of the inne ing space is the same as that of the beaing boe. Recommend maintaining a toleance of F6 o bette. Spaces

98 9. SPACERS Pat 1 Pat 2 Pat 3 Pat 4 Pat5 Pat 6 Pat 7 Pat 8 Position of the Spay Nozzle The following table lists positions of a spay nozzle fo oil-ai, oil mist, and oil jet lubicating systems. N10XXMR N10XXR Nominal 79 Seies 70 Seies 72 Seies Boe Numbes (Standad seies) (ROBUST seies) Beaing Boe A ( 1 ) B A ( 1 ) B A ( 1 ) B A B A B ( 1 ) In compliance with DIN Standad Unit: mm BNR19 BNR10 BAR10 Nominal BGR19 BGR10 BGR02 BER19 BER10 BTR10 Beaing Boe A B A B A B A B A B A B Unit: mm Fig. 9.2 Position and Diection of Spay Nozzle Attention Fo beaings opeating unde nomal opeating speed, pope lubication can be achieved by positioning the nozzle boe along the side of the beaing and aiming diectly into the beaing inteio at the level of the inne ing. Fo constant high speed opeations, it is advantageous to position the nozzle boe so that the lubicant is diected into the beaing inteio at an angle of about 15 o 20. Please contact NSK fo futhe details. An appopiate means of daining oil sump is necessay to pevent sevee oil shea fiction, which can esult in beaing damage at the sliding section. Recommend using a maximum 5 micon filte to povide filtation of oil enteing the lubicating system. Fig. 9.1 Angle of nozzle B IN A B IN A Spaces

99 BEARING HANDLING Pat6 Mounting Beaing Handling 1. Mounting P Cleaning the Beaings and Related Pats 2. Checking Dimensions of Related Pats 3. Mounting Pocedues 4. Inspection afte Mounting 2. Opeating Inspection P Initial Running-in Pocedues P Opeating Inspection Initial Running-in Pocedues Beaing Hand ling

100 1. MOUNTING Pat 1 Pat 2 Pat 3 Pat 4 Pat 5 Pat6 Pat 7 Pat 8 Intoduction Mounting Pocedue The method of mounting olling beaings stongly affects thei accuacy, life, and pefomance. It is ecommended that the handling pocedues fo beaings be fully analyzed by designes and enginees and that standads be established with espect to following items: Handle beaings caefully Avoid any heavy shocks duing handling. Shock loads can scatch o othewise damage a beaing, possibly esulting in failue. An excessively stong impact may cause binelling, beakage, o cacks. 1. Cleaning the Beaings and Related Pats Deliveed beaings ae coated with an anti-coosion agent fo dustpoofing and ust pevention duing tanspotation. Afte opening the package, beaings need to be cleaned in ode to emove the anti-coosion agent. Some beaings, such as sealed o pegeased beaings, can eached a constant and stable tempeatue. Using a micomete o cylinde gauge, take measuements at seveal diffeent points to confim thee ae no significant diffeences in measuement values. Recommended measuements fo accuacy of the shafts and housing boes ae listed on Page 185. Mounting 1. Cleaning the beaings and elated pats 2. Checking the dimensions of elated pats 3. Mounting pocedues 4. Inspection afte mounting Use pope tools Always use the pope equipment when handling beaing. Do not use geneal pupose tools. Pevent coosion Handling beaings with bae hands can coode the beaing be used without cleaning. Cleaning method 1. Use keosene o light oil to clean the beaings. 2. Use sepaate tanks fo ough cleaning and final Inspection of spaces Fo main spindle, a space paallelism of less than mm is ecommended. Space paallelism exceeding this ecommendation will tilt the beaings, thus causing inaccuacies and beaing noise. Beaings should not be unpacked until immediately befoe mounting. Howeve, beaings fo instuments o fo high speed opeations must fist be cleaned with clean filteed oil in ode to emove the anti-coosion agent. Afte the beaings ae cleaned with filteed oil, they should be potected to pevent coosion. Pelubicated beaings must be used without cleaning. Beaing mounting pocedues vay accoding to the type of beaing and type of fit. sufaces because of the acidic moistue o othe contaminations on the hands. Keep you hands clean when handling beaings, and wea dust fee gloves wheneve possible. Take measues to pevent usting of beaings caused by moistue and coosive gasses. Stoage method Although beaings ae coated with an anti-coosion agent, and then wapped and packed, it is impossible to cleaning. Each tank should be equipped with a wie ack to pevent diect contact of the beaing with any contamination that may have settled at the bottom. 3. In the ough cleaning tank, avoid otating the beaings. Afte cleaning the outside sufaces with a bush, move the beaings to the final cleaning tank. 4. In the final cleaning tank otate the beaing by hand. 3. Mounting Pocedues Gease lubicated beaings and oil-ai (oil mist) lubicated beaings which ae cleaned ae mounted on the shaft and housing boe. Pocedues fo mounting vay accoding to the fit equiements of the inne and oute ings. Pimaily, it is the inne ing of a machine tool beaing that otates, thus beaings with cylindical boes ae usually mounted by heating them to expand the inne ing (shink fit). Since pecision beaings ae widely used fo otating shafts, thei inne ings equie a tight fit. Beaings with cylindical boes ae usually mounted by fitting with a pess (pess fit), o by heating them to expand thei inne ing (shink fit). The oute ing is usually inseted into the housing with a loose fit. In case whee the oute ing has an completely avoid exposue to the ai suounding the beaings. Stoe the beaings in a dy location and avoid exposue to moistue and humidity. Beaings should be stoed in a clean, dy, and wellventilated location that also povides potection fom diect sunlight. Stoe the beaings in a locke o on shelves that ae Make sue that the cleaning fluid in the final cleaning tank is kept clean. 5. Remove excess cleaning fluid fom the beaings afte cleaning. Beaings using odinay gease lubication need to be Beaing with tapeed boes can be mounted diectly onto a tapeed shaft. Fo high speed opeations, GN gauges ae ecommended fo attaining accuate adial cleaance when mounting. Page 202 povides details on how to use GN gauges. intefeence fit, a pess may be used. Pecautions fo Pope Handling of Beaings Since olling beaings ae high pecision machine pats, they at least 30 cm fom the floo. When beaings ae unpacked fo acceptance inspection, take measues to pevent usting and contamination. Afte inspection, follow the guidelines given above to ensue packed with gease. Oil lubicated beaings should be mounted on the machine tool spindle while taking cae not to otate the beaing. Pio to mounting, slightly coat the beaing inne and oute suface aeas with a Oute ings ae mounted with some cleaance; so mounting tool ae not usually equied. The housing can be heated to make mounting much easie. must be handled accodingly. pope stoage. thin film of lubication oil. Even if high quality beaings ae used, thei expected pefomance cannot be achieved if they ae not handled 2. Checking Dimension of Related Pats popely. The main pecautions to be obseved ae as follows: Inspection of shaft and housing Mating housing and shaft sufaces should be cleaned and Keep beaings and suounding aea clean checked fo flows o bus. Foeign paticles, even if invisible to the naked eye, have The dimensions of the shafts and housing boes should be hamful effects on beaings. Take cae to pevent the enty of checked to confim a matching fit with the beaing boe and dit and debis into the beaing by maintaining a clean woking oute diamete. Recommended fits fo shafts and housing envionment. boes ae listed on Page 184. Take measuements and mount the beaings in a themostatic chambe. Pats should be left until they have

101 1. MOUNTING Pat 1 Pat 2 Pat 3 Pat 4 Pat 5 Pat6 Pat 7 Pat Mounting of Beaings with Cylindical Boes (1) Pess fit (2) Shink fit Since pess fitting lage beaings equies a geat deal of 3.2. Pecautions fo Mounting Angula Contact Ball Beaings Fig. 1.3 Diection of Load fo Angula Contact Ball Beaings Fitting with a pess is widely used fo small beaings. Fist, foce, the shink fitting method is widely used. The Due to design estiction, an angula contact ball beaing can apply a thin coat of oil to the mating shaft suface befoe mounting to help educe the amount of foce equied fo pess fitting. beaings ae fist heated to expand the inne ing befoe mounting onto the shaft. This method pevents excessive foce fom being imposed on the beaings and enables sustain loads in only one diection. Theefoe, when mounting angula contact ball beaings onto the shaft o into the housing, it is impotant not to apply any load in the wong Mounting Next, place a mounting tool against the inne ings as shown in Fig Apply steady pessue fom the mounting tool to dive the beaing fimly against the mounting them in a shot time. The expansion of the inne ing fo vaious tempeatue diffeences and beaing sizes is shown in Fig diection. Pay special attention to the ode of mounting fo combination Damage Load applied in diection x esults in damage to the beaing. shoulde of the shaft. The following pecautions need to be taken when shink beaings. Mounting onto the shaft and into the housing is Avoid pess fitting onto a shaft by applying pessue to fitting. diffeent fo Back-to-back and Face-to-face aangements. the oute ings as this may damage the beaing. 1. Do not heat beaings to moe than 120 C. Also, avoid using a hamme when mounting pecision beaings. Fo sepaable beaings, such as cylindical olle beaings, the inne and oute ings can be mounted onto the shaft and into the housing as sepaate units. When assembling the two units, take exta cae to align the inne and oute ings coectly. Caeless o foced assembly may cause 2. Heat the beaings to a tempeatue 20 C to 30 C highe than the lowest tempeatue equied fo mounting without intefeence since the inne ing will cool a little duing mounting. 3. Afte mounting, the beaings will shink in the axial diection as well as the adial diection while cooling. Theefoe, dive the beaing fimly up against the shaft Back-to-back aangement: ➀ Pess the beaing onto the shaft. ➁ Tighten the beaing locknut fo peloading. ➂ Inset the beaing and the shaft into the housing, and attach the etaining cove. Fig. 1.4 Mounting of Back-to-back Aangement scatches on the olling contact sufaces. shoulde using locating methods to eliminate any cleaance between the beaing and shoulde. Fig. 1.1 Pess Fitting Inne Ring Fig. 1.2 Tempeatue and Themal Expansion of Inne Ring 240 Boe expansion, µm Tempeatue diffeence T=80 C 70 C 60 C 50 C 40 C 30 C 20 C 5 p6 n6 m5 k5 j5 Face-to-face aangement: ➀ Pess the beaing into the housing. ➁ Secue the etaining cove fo peloading. ➂ Inset the shaft into the inne ing and tighten the beaing locknut. Fig. 1.5 Mounting of Face-to-face Aangement Boe diamete, mm Revese the ode of each step fo dismounting

102 1. MOUNTING Pat 1 Pat 2 Pat 3 Pat 4 Pat 5 Pat6 Pat 7 Pat Secuing the beaing (1) Secuing the inne ing The inne ing is usually secued onto the shaft by tightening the beaing locknut, which explains why pependiculaity of the theads and end face ae vey impotant. Even if accuacy as a single component is good, the gap between the shaft and locknut can esult in unout of the locknut, causing the shaft and beaing to bend (see Fig. 1.21, Page 207). Theefoe, making adjustments ae necessay to ensue constant unning accuacy. It is also impotant that the locknut be completely tightened so as to eliminate any possibility of it becoming loose. Seating toque infomation fo beaing locknuts is shown in Table 1.1. Thee is a isk of unbalance due to face and unout of the locknut o a mino inaccuacy of the mating pats. Hee, sleeves ae widely used in high speed, high pecision machine tool spindles to secue the beaing to the shaft by a lage intefeence fit between the shaft and sleeve boe. Howeve, the sleeve tends to become loose afte continuous opeation, so it must be checked peiodically. When a wide space is used between combined angula contact ball beaings, and the seating toque of the locknut is excessive, the inne ing space may become defomed and alte the peload to a level highe than expected. It is necessay to conside this defomation when the peload is set. (2) Secuing the oute ing A etaining cove held by bolts is geneally used to secue the beaing oute ing axially. If a bolt is tightened excessively o a combination of bolts is tightened unevenly, the beaing oute ing may become defomed. Fo example, Fig. 1.6 shows possible defomation of the oute diamete of the oute ing caused by uneven tightening of the etaining cove, when the oute ing end face is pessed as a pilot ing. Fig. 1.7 shows an example of poo etaining cove tightening fo a fixed end beaing esulting in oute ing defomation. Fig. 1.8 shows defomation of an oute ing aceway suface caused by tightening of a double ow cylindical olle beaing. The amount of defomation depends on the cleaance of the mating pats. It is ecommended that the cleaance between the etaining cove and housing end face be adjusted to about 0.01 to 0.05 mm befoe the bolts ae completely tightened. Fig. 1.6 Raceway Suface Defomation Caused by Excessive Tightening Befoe tightening 1 µm 1 µm Fig. 1.7 Raceway Suface Defomation Caused by Excessive Tightening Fig. 1.8 Defomation of the Oute Ring of a Double Row Cylindical Rolle Beaing Caused Excessive Tightening Bolts δ (8 places) Adjusted amount Retaining cove A B Change in boe diamete of oute ing, δm Afte tightening NN3020 Oute ing Applied toque, N cm Retaining cove (B side) (A side) Bolts (4 places) Oute ing Evaluated aea Adjusted Bolts amount (6 places) 1 µm 1 µm Evaluated aea (Oute ing) Tightening adjusted by 10 µm Tightening adjusted by 50 µm Table 1.1 Beaing Locknut Tightening Toque and Cleaance between Retaining Cove and Housing Nominal beaing boe Locknut tightening Locknut tightening Cleaance between etaining (mm) foce (N) toque Refeence (N m) cove and housing (mm) When intefeence fit of the shaft inceases unde high speed opeations, the amount of tightening toque applied to the locknut must also be inceased. The tightening foce of angula contact thust ball beaing fo ball scew suppot should be times of the peload. Convesion equation of locknut tightening toque T=0.5F d p tan (p +β )+d w µ w [N mm] The values of locknut tightening toque in the table ae calculated by fiction coefficient of T :Locknut tightening toque [N mm] F :Locknut tightening foce [N] d p :Effective diamete of locknut [mm] p :Fiction angle of locknut suface p =tan 1 µ S µ S :Fiction coefficient of locknut suface d w :Fictional toque equivalent diamete at locknut suface [mm] µ w :Fiction coefficient of locknut suface β :Lead angle of nut β =tan 1 (pitch/(3.142 dp)) Equation of push up foce µ :Fiction coefficient at fitting suface [=0.12] p m :Suface pessue [MPa] d :Shaft diamete [mm] B :Beaing width [mm] d :Effective intefeence [mm] E :Young s modulus of steel [MPa] k :Wall thickness atio (k=d/d i ) D i :Raceway diamete of inne ing [mm] k 0 :Wall thickness atio of hollow shaft (k 0 =d 0 /d) :Boe diamete of hollow shaft [mm] d 0 Mounting

103 1. MOUNTING Pat 1 Pat 2 Pat 3 Pat 4 Pat 5 Pat6 Pat 7 Pat Mounting of Cylindical Rolle Beaings (1) Measuing adial cleaance of cylindical olle beaings A GN gauge is an instument fo matching the tapeed section of a shaft to the tapeed boe of a beaing when mounting a cylindical olle beaing with a tapeed boe onto a machine Fig. 1.9 GN Gauge Dial gauge Main body fixtue GN30XX Gauge body Handle ➄ Mounting of inne ing Mount the inne ing onto the shaft and tighten the locknut lightly. At this time, the beaings should be cleaned, but not yet coated with gease. ➅ Setting of GN gauge Adjust the setscew on the GN gauge (0.2 mm to 0.3 mm on the dial Fig Insetion of Inne Ring Mounting tool spindle. Afte mounting, the GN gauge is used fo pecise face) to spead open the dial on the GN gauge. The GN gauge is placed contol of the beaing s adial intenal cleaance. This in the cente of inne ing and the setscew is loosened. instument is especially effective when a cylindical olle beaing is used with adial peload. Fig. 1.9 descibes the GN gauge components. Pointe contol Setscew NIPPON SEIKO ➆ Reading of the scale Read the scale on the dial gauge of the GN gauge at this time. Example 1: A half-shift of the dial fom zeo in a clockwise diection Fig Setting of GN Gauge indicates positive cleaance. Example 2: A half-shift of the dial fom zeo in a counte-clockwise How to use a GN gauge ➀ Inset oute ing into housing Fig Zeo Setting of Cylinde Gauge diection indicates negative cleaance. The ecommended fit between oute ing and housing is: Cleaance 2 µm - Intefeence 2 µm ➁ Zeo setting of cylinde gauge Confim that the tempeatues ae the same fo the oute ing (inseted into the housing), the inne ing, and the shaft. Then, measue the boe diamete of the oute ing at about fou diffeent locations. Detemine the aveage fo the measuements and the cylinde gauge to zeo (see Fig. 1.10). ➂ Adjust the inscibed diamete of GN gauge Loosen the bolt of the main body fixtue on the GN gauge. Apply the cylinde gauge to the inscibed diamete suface of the GN gauge and adjust the setscew to the setting of the dial on the cylinde gauge to zeo (see step ➁). (Use the GN gauge in an upight position to avoid inaccuacies due to its own weight.) Example 1: Pointing to 4 in a Example 2: Pointing to 2 in a clockwise diection indicates a counte-clockwise diection adial cleaance of mm indicates a adial cleaance of mm ➇ Adjustment In addition to pocedues given in step ➅, use the scew to spead the dial of the GN gauge. Remove the gauge fom inne ing and tighten the locknut. Repeat steps ➅ though ➇ until the scale of the dial gauge eaches the taget cleaance value. Fig Reading of the Scale Fig Measuement of Space Width ➃ Coection of GN gauge Using the esults fom step ➂, use the pointe contol on the dial gauge to adjust the pointe on the GN gauge to the ed mak fo gauge coection. Confim that the shot needle is nea 2 on the dial. (Gauge coection coects fo elastic defomation of the olle due to measuing pessue on the gauge. The amount of coection fo each gauge is detemined upon shipment a gauge.) Fig Adjust the Inscibed Diamete of the GN Gauge ➈ Adjustment of space Measue the cleaance between the shaft shoulde and the end face on the lage diamete side of NN30XXKR by using block gauge. Measue moe than thee places on cicumfeence to both an aveage and the finish width of space fo that aveage

104 1. MOUNTING Pat 1 Pat 2 Pat 3 Pat 4 Pat 5 Pat6 Pat 7 Pat 8 (2) Measuing adial cleaance of cylindical olle beaings (GN gauge is not used) When the GN gauge is not used, it is necessay to adjust the space width by consideing the following two items: Shinkage of oute ing aceway diamete due to fitting in housing ( e ) Expansion of the inne ing aceway diamete due to fitting, which includes a hollow shaft atio ( i ) Calculation of The finish dimension (La) of the space, which is used fo setting the post-mounting adial cleaance of, can be calculated as follows: Measuing of adial cleaance of m ➀ Mount the inne ing onto the tapeed section of the shaft. (At this point, degease the tapeed section of the shaft and intenal suface of the inne ing with oganic solvent.) ➁ Place the oute ing on the cicumscibing pat of the olles and apply the dial gauge to oute diamete of the oute ing. Fig Insetion of Oute Ring Block gauge L Dial gauge Mounting by lightly tapping the space Mounting L a = L K ( m + e ) ➂ Tighten the space and the locknut now to expand the inne ing (see Fig. 1.16). Fig Measuing Oute Ring Movement Table 1.2 Hollow Shaft Ratio and Coefficient K Hollow shaft Ratio k 0 Coefficient K 45 55% % % 16 Calculation of e e =(D h D) h when e 0 assume e =0 L a D h D h : Finish dimension of space fo setting post mounting adial cleaance L : Width of block gauge (Measued esult fom step ➄ on Page 205.) m : Movement of the oute ing in adial diection (Measued esult fom step ➃ on Page 205.) : Radial cleaance afte mounting e : Shinkage of oute ing aceway diamete due to fitting K : Coefficient (Conveted value which includes shinkage of a hollow shaft with a 1/12 tapeed hole) k 0 : A/B 100 A: Shaft boe diamete B: Shaft oute diamete : Housing boe diamete : Oute diamete of oute ing (Refe to beaing inspection sheet) : Shinkage ate of the oute ing aceway diamete (0.62 fo NN30 and N10 seies) (0.7 fo NN39 and NN49 seies) ➃ Push the oute ing in up and down and measue the adial movement of the oute ing with dial gauge ( 1 ). Repeat steps ➂ and ➃ until play of the oute ing ( m ) becomes about mm ( 2 ) (Fig. 1.17). ➄ When m is set at about mm, measue the distance fom shaft shoulde to the inne ing end face (Dimension L) with block gauge and the thickness gauge ( 3 ) (see Fig. 1.18). Remaks ( 1) If the measuement takes too long, the tempeatue of the oute ing may have isen to body tempeatue esulting in an eoneous measuement. Weaing gloves is ecommended to fo making a quick measuement. ( 2) If thee is an excessive amount of play, the oute ing may have defomed into an ellipse when pessed by hand. This would esult in an eoneous measuement. Theefoe, mm of play is acceptable. (0.005 mm is the taget value, but mm to mm is also acceptable.) ( 3) Fo the measuement of dimension L, the value obtained is poduced by inseting the block gauge in the left half of the zone shown in Fig (This is due to tilting that occus between the shaft shoulde and inne ing end face.) Inne ing Acceptable ange fo inseting block gauge Dial gauge m Rolle Oute ing Fig Measuing Width Dimension with Block Gauge Unacceptable ange fo inseting block gauge (Example of calculation) Setting adial cleaance to = mm fo NN3020MBKR afte mounting. Shinkage of oute ing aceway diamete due to fitting: e = (Intefeence) (When e 0 assume e = 0) Movement of oute ing (Measued value in step ➃): m = mm Block gauge width (Measued value in step ➄): L = mm Finish space width dimension: L a = (0.007 ( 0.002) 0.004) = = Note the code!

105 1. MOUNTING Pat 1 Pat 2 Pat 3 Pat 4 Pat 5 Pat6 Pat 7 Pat Gease Packing Pocedue fo packing gease afte cleaning beaings A apid ise in tempeatue may occu duing initial unning-in due to impope packing of gease. This can esult in a long unning-in peiod, o lead to seizue and beaing failue. Following pope pocedues fo packing gease and using the coect amount of gease deseves caeful attention. Recommended pocedues ae as follows: Packing method fo cylindical olle beaings (1) Coat about 80% of the gease amount evenly on olle olling suface. Avoid putting too much gease on the cage boe. Gease on the cage boe is difficult to dispese duing the unning-in peiod, which can esult in a apid ise in tempeatue o a long unning-in peiod. (2) Coat olle sufaces with a thin film of gease, including the olle end faces, olle cage contact points, and along the face edges of each cage pocket. (3) Using the emaining 20% of gease, apply a thin film of 4. Inspection afte Mounting 4.1. Runout accuacy Accuate mounting and elated pats ae indispensable to ensue pecision and accuacy of the machine tool spindle. 1: Assembled beaing oute ing face unout with aceway fo angula contact ball beaings. Adjust to mm o less by tapping on the oute ing end face. 3: Concenticity of ea side housing mm o less. If these accuacies cannot be met, disassemble the beaings and check the accuacy of pats again. Fig Tilting the Shaft Locknut Mounting 1. Pe-inspection Check to ensue thee is no foeign matte in the beaing inteio. Beaings fo high speed spindle shafts should be cleaned, degeased, and packed with gease. Fo othe applications, emove any anti- gease to the aceway suface of the oute ing. 2: Vaiation of beaing outside suface geneatix inclination with oute ing efeence face fo angula contact ball beaings. Adjust to mm o less tilting the locknut (see Fig. 1.21). Tap the nut hee. coosion agent adheing to inteio sufaces of the beaings. 2. Gease dispenses Use a gease dispense, such as a plastic syinge fo Fig Gease Packed Angula Contact Ball Beaing Fig Runout Accuacy of Machine Tool Spindle pecision gease dispensing. If possible, use a Rotate shaft dispense that comes with a gauge fo packing accuate amounts of gease. 3. Amount of gease Recommended amounts of gease packing fo pecision beaings: Angula contact ball beaings fo high speed machine tool spindles: 15% ± 2% of intenal space Cylindical olle beaings fo high speed machine tool spindle: 10% ± 2% of intenal space Fig Gease Packed Cylindical Rolle Beaing Ball beaings fo motos: 20% to 30% of intenal space Recommendation of gease amount fo vaious beaing types and numbes is shown on Page 175. Rotate beaing oute ing Packing method fo ball beaings (1) Pack gease evenly between the balls. If an oute ing guided cage is used, such as a phenolic esin cage, apply a light coating of gease on the guided suface. (2) Rotate the beaing by hand to spead gease evenly on the sufaces of the aceway, ball, and cage. Assembled beaing oute ing face unout with aceway fo angula contact ball beaings Retaining cove Base Vaiation of beaing outside suface geneatix inclination with oute ing efeence face fo angula contact ball beaings Concenticity of ea side housing

106 1. MOUNTING Pat 1 Pat 2 Pat 3 Pat 4 Pat 5 Pat6 Pat 7 Pat Contol of Peload afte Mounting of Beaings If the peload of olling beaing is set lage, the igidity of beaing is inceased, but heat geneation is also inceased, and in exteme cases, seizue may occu. Theefoe, it is necessay to contol optimum peload caefully in esponse to opeating condition. Measuing method of peload fo angula contact ball beaing is intoduced below. Fo the peload of cylindical olle beaing, it is ecommended to contol by using a GN gauge in mounting pocess (see Page 202). Measuing of peload fo angula contact ball beaings Thee ae thee methods fo checking peload of beaings afte mounting onto the main shaft: stating toque method, thust static igidity method, and natual fequency method. Featues of these methods ae summaized in Table 1.3. Table 1.3 Advantage Disadvantage Stating toque method Thust static igidity method Natual fequency method Used fo heavy peload, If stating toque is high, measuement eo is small. Not good fo light peload. If stating toque is small, vaiation of measuement is lage. Used fo light peload (1) Stating toque method [Chaacteistic] High speed main shaft spindle beaings ae often used with light peload so that stating toque is low and measuement eo is lage. Not good fo heavy peload. Loading equipment is too lage scale. Affected easily by defomation of contact pat othe than beaing. Fig Stating Toque Method Measuement of stating toque Measuement accuacy is high. Good epeatability. Influence of spindle fixing condition should not be ignoed. Rotay toque mete Housing Block (2) Thust static igidity method [Chaacteistic] When axial igidity of the beaing is high, axial foce necessay fo measuement becomes vey high and loading equipment is necessay (Example: If axial igidity is 200N/µm, 2 000N load is needed to geneate 10 µm displacement). When measuement load is lage, besides elastic defomation of beaing inteio, effect of suface defomation and elastic defomation of othe elated pats ae added. Measued igidity tends to be lowe than theoetical value and eo often occus. [Method] Thust load is applied to shaft and its axial displacement is measued fo obtaining peload (see Figs and 1.26). (3) Natual fequency method [Chaacteistic] Measuing sensitivity is the highest and epeatability is good, but tend to be affected by spindle fixing condition. [Method] Shaft is vibated in an axial diection and esonance fequency of shaft is measued at the same time. Peload can be obtained by the esonance fequency (see Figs and 1.28). Fig Thust Static Rigidity Method Thust load F a Fig Relation between Axial Displacement and Peload Axial displacement, mm Dial gauge Shaft DB aangement of 65BNR10STYN Peload afte mounted N 550 N Axial load, N Fig Natual Fequency Method Vibate in thust diection Acceleation pickup senso FFT analyze Shaft Housing Block Housing Block Fig Relation between Resonance Fequency of Main Shaft and Sping Constant Mounting [Method] Stating toque is obtained mainly by measuing tangential foce (see Fig. 1.23). Peload is obtained fom the elationship between measued stating toque and peload (see Fig. 1.24). When oil film fomation in olling contact aea is unstable duing measuement, sticking occus (Rotation does not stat even unde tangential foce and otation stats suddenly when tangential foce is inceased gadually). The toque at such occasion tends to be highe than pedicted calculated toque so that the excessive measuement esult needs to be excluded. Shaft Fig Relation between Stating Toque and Peload Stating toque, N mm DB aangement of 65BNR10STYN Peload afte mounted, N Measuement of esonance fequency (Fz) fo main shaft in axial diection d Axial sping constant of main shaft d Convet Convet Peload afte mounted K a : Axial sping constant of beaing (N/µm) F z : Resonance fequency (Hz) : Mass of otating body (kg) m K F z= 1 π m a Resonance fequency of main shaft, Hz Peload afte mounted, N Axial sping constant, N/µm Peload Axial sping constant, N/µm

107 2. OPERATING INSPECTION Pat 1 Pat 2 Pat 3 Pat 4 Pat 5 Pat6 Pat 7 Pat 8 Opeating Inspection Table 2.1 Cause and Countemeasues fo Opeating Iegulaities Afte mounting has been completed, a test un should be conducted to detemine if the beaing has been mounted coectly. Small equipment may be manually opeated to assue that they otate smoothly. Items to be checked include sticking due to foeign matte, visible flaws, uneven toque caused by impope mounting, o an impope mounting suface. Othe items include excessive toque caused by an inadequate cleaance, mounting eos, o seal fiction. If thee ae no abnomalities, then a poweed test un can be stated. Fo high-speed equipment, pefom unning-in pocedues befoe a poweed test un (Pages ). A poweed test un should be stated slowly without load. Make close obsevations to detemine whethe o not abnomalities exist. If eveything seems satisfactoy, then gadually incease the speed, load, etc., until nomal opeating conditions ae eached. Duing a test un opeation, check fo abnomal noise, excessive ise of beaing tempeatue, leakage and contamination of lubicants, etc. If any abnomality is found, stop the test un immediately and inspect the machiney. If bette to diectly measue the tempeatue of the oute ing using oil holes fo access. The beaing tempeatue should ise gadually to a steady level within one o two hous afte opeation stats. If the beaing expeiences touble, o if an eo was made in mounting, the beaing tempeatue may incease apidly and become abnomally high. The cause of this abnomal tempeatue may be an excessive amount of lubicant, insufficient beaing cleaance, incoect mounting, o excessive fiction of the seals. In the case of high speed opeations, an incoect selection of beaing type o lubicating method may also cause an abnomal tempeatue ise. Beaing noise can be checked with an acoustic o othe instuments. Abnomal conditions ae indicated by a loud metallic sound, o othe iegula noise. Possible causes include incoect lubication, poo alignment of the shaft and housing, o the enty of foeign matte into the beaing. Possible causes and countemeasues fo iegulaities ae listed in Table 2.1. Noise Iegulaities Possible cause Countemeasues Loud metallic Abnomal load Incoect mounting Impove the fit, intenal cleaance, peload position of housing shoulde, etc. Impove the machining accuacy and alignment of shaft and housing, accuacy of mounting method. sound ( 1 ) Insufficient o impope lubicant Replenish the lubicant o select anothe lubicant. Contact of otating pats Modify the labyinth seal, etc. Dents geneated by foeign matte, Replace o clean the beaing, impove the seals, and coosion, flaws, o scatches on aceways use clean lubicant. Loud egula sound Binelling Replace the beaing, and use cae when handling beaings. Iegula sound Flaking on aceway Excessive cleaance Penetation of foeign paticles Flaws o flaking on balls Excessive amount of lubicant Insufficient o impope lubicant Replace the beaing. Impove the fit, cleaance, and peload. Replace o clean the beaing, impove the seals, and use clean lubicant. Replace the beaing. Reduce amount of lubicant, o select stiffe gease. Replenish lubicant o select a bette one. Opeating Inspection necessay, the beaing should be dismounted fo examination as well. Although the tempeatue of the outside suface of the housing can geneally help detemine beaing tempeatue, it is Abnomal tempeatue ise Abnomal load Incoect mounting Impove the fit, intenal cleaance, peload, o position of housing shoulde. Impove the machining accuacy and alignment of the shaft and housing, accuacy of mounting, o mounting method. Ceep on fitted suface, excessive seal fiction Coect the seals, eplace the beaing, o coect the fitting o mounting. Vibation (Radial unout of shaft) Binelling Flaking Incoect mounting Penetation of foeign paticles Replace the beaing and use cae when handling beaing. Replace the beaing. Coect the squaeness between the shaft and housing shoulde o side of space. Replace o clean the beaing, impove the seals. Leakage o discoloation Too much lubicant. Penetation by Reduce the amount of lubicant, select a stiffe gease. Replace of lubicant foeign matte o abasion chips the beaing o lubicant. Clean the housing and adjacent pats. Note ( 1 ) Squeaking may aise fom gease lubicated ball beaings o cylindical olle beaings (medium to lage sized). This is especially tue duing winte when tempeatues ae low. In geneal, even though squeaking may occu, the beaing tempeatue will not ise, leaving fatigue o gease life unaffected. Consequently, such a beaing can continue to be used. If you concens egading squeaking noise, please contact NSK

108 3. INITIAL RUNNING-IN PROCEDURES Pat 1 Pat 2 Pat 3 Pat 4 Pat 5 Pat6 Pat 7 Pat 8 Pepaations The following unning-in pocedues ae necessay afte popely mounting beaings. Balance of Shaft and Assembly Any unbalance of otating components will cause epeated stess o excessive vibations due to centifugal foce. This is especially tue fo spindles, which ae opeated at a d m n value of o highe. Theefoe, it is impeative that both the shaft assembly ae well balanced. Spindle Assembly Spindle assemblies with a V-belt dive should have misalignment of the spindle pulley cente and moto pully cente coected to a taget of 0.1 mm o less. Coupling joints should have misalignment of the spindle shaft cente and moto shaft cente coected to a taget of 0.01 mm o less. Initial Running in Methods If opeating speed is suddenly inceased afte the beaings ae mounted, the opeating tempeatue will ise abuptly and beaing failue may occu. Gease lubicated beaings, especially, equie that you follow pope unning-in pocedues. Incease opeating speed gadually to completely oient the initially filled gease on each contact suface aceway. Running in should be conducted unde ambient tempeatue conditions (15 C to 25 C) while monitoing beaing tempeatue. Maximum opeating tempeatue of the spindle housing exteio should be tageted at about 50 C. Do not to exceed 55 C. If a apid tempeatue incease occus, tempoaily stop the unning-in pocess o deceleate to lowe the tempeatue. Some spindle assemblies incopoate both cylindical olle beaings and angula contact ball beaings. Since cylindical olle beaings tend to expeience a moe apid tempeatue incease in compaison with ball beaings, timing of speed inceases must be set to coespond with the olle beaings. [Caution] Spindle assemblies opeating unde oil mist and oil-ai lubicating conditions isk a sudden tempeatue ise at initial opeation, o afte the spindle assembly has not been opeated fo a long time. Excess oil that has collected in the oil lines of the lubication system may suddenly flood the beaing inteio, causing a tempeatue spike. Pefoming unning-in pocedues fo beaings with these lubicating systems equie much less time than gease-based systems, and ae highly ecommended. (1) Continuous unning-in pocedue [Featue] Continuous unning-in woks by gadually inceasing opeating speed fom the low speed zone. Although somewhat time consuming, this pocedue helps machine opeatos to detect potential poblems elated to the main shaft, thus Fig. 3.1 Tempeatue Change of Constant Speed Running-in Opeation avoiding costly damege to the beaings. [Method] 90 Maximum opeating speed of the application is achieved by Side A beaing Beaing: 65BNR10HTYNDB 80 Side B beaing epeating seveal steps in a cycle. Maximum opeating speed: min 1 Base, C Step 1. Begin at a easonably low opeating speed. 70 Room, C 18h Step 2. Monito fo tempeatue ise. 60 Step 3. Stable tempeatue is eached. 50 Step 4. Continue incemental inceases of opeating speed. 40 Continue epeating the above cycle until an equilibium 30 tempeatue is eached at the maximum opeating speed 20 and divide it into ten stages to detemine the taget speed 10 fo each stage. Then, epeat the above cycle fo one o two 0 hous until the taget speed is eached fo that stage. Move Time, h up to the next stage and epeat the above cycle until you each the next taget speed. Tempeatue, C Fig. 3.2 Incease of Opeating Speed Continuous Running in Beaing tempeatue Tempeatue dops Incease opeating speed Time (2) Intemittent Running-in pocedue [Featue] Intemittent Running in woks by stopping opeation and stabilizing tempeatues befoe thee is a apid tempeatue ise, which is caused by a sudden supply of gease to the beaing inteio duing initial opeation. This pocedue allows us to shoten the amount of time equied fo unning in. Pocedues fo intemittent unning in vay fom machine to machine and beaing aangements. Be sue to confim the beaing aangement fo each spindle application. [Method] Fist, take the maximum opeating speed and divide it into eight o ten stages to detemine the maximum taget speed fo each stage. Each stage is divided into 10 cycles that ae appoximately one minute long. Duing each cycle, apidly acceleate the spindle assembly to the taget speed fo the cuent stage deceleate back to zeo. Repeat this cycle about 10 times. Move up to the next stage and epeat the above cycle 10 times fo the taget speed of that stage. Fig. 2.3 shows tempeatue ise data fo a beaing with a maximum opeating speed of min 1. The maximum speed was divided into 8 stages with 10 cycles each of apid acceleation and deceleation. Fig. 2.4 shows an example of 1 cycle. And it is desiable to make it otate slowly by about 500 min 1 fo 15 minutes, and to familiaize gease and befoe opeating stat. As fo afte an opeation end, it is desiable to pefom fixed opeation about 1 hou at maximum speed. Beaing tempeatue Stable tempeatue Incease opeating speed Time Tempeatue, C Beaing: 65BNR10HTYNDB Maximum opeating speed: min 1 2h Time, h Side A beaing Side B beaing Base, C Room, C 1 cycle fo taget speed min 1 (10 cycles pe stage; 8 stages pe unning in) n Beaing tempeatue Tempeatue still ising S 15 S 2.5 S 40 S 1 minute of 1 cycle Do not incease opeating speed Within acceptable limits Within acceptable limits Stop the unning-in pocess Incease opeating speed when tempeatue ise chaacteistics ae within limits. Time Fig. 3.3 Tempeatue Change of Intemittent Running-in Opeation Fig. 3.4 One Cycle fo Intemittent Running-in Pocedue Initial Running-in Pocedues

109 BEARING FAILURE DIAGNOSIS Pat7 Beaing Failue and Countemeasues Beaing Failue Diagnosis 1. Beaing Failue and Countemeasues P Diagnosis with Sound and Vibation P Diagnosis with Sound and Vibation Beaing Failue Diagnosis

110 1. BEARING FAILURE and COUNTERMEASURES Pat 1 Pat 2 Pat 3 Pat 4 Pat 5 Pat 6 Pat7 Pat 8 Maintenance, Inspection and Coecting Iegulaities In ode to maintain the oiginal pefomance of a beaing fo as long as possible, pope maintenance and inspection should be pefomed. If pope pocedues ae used, many beaing poblems can be avoided and the eliability, poductivity, and opeating costs of the equipment containing the beaings ae all impoved. It is suggested that peiodic maintenance be done following the pocedue specified. This peiodic maintenance encompasses the supevision of opeating conditions, the supply o eplacement of lubicants, and egula peiodic inspection. Items that should be egulaly checked duing opeation include beaing noise, vibation, tempeatue, and lubication. If an iegulaity is found duing opeation, the cause should be detemined and the pope coective actions should be taken afte efeing to Table 2.1. If necessay, the beaing should be dismounted and examined in detail. Beaing Failue and Countemeasues In geneal, if olling beaings ae used coectly they will suvive to thei pedicted fatigue life. Howeve, they often fail pematuely due to avoidable mistakes. In contast to fatigue life, this pematue failue is caused by impope mounting, handling o lubication, enty of foeign matte, o abnomal heat geneation. Fo instance, the causes of ib scoing, as one example, ae the use of impope lubicant, faulty lubicant system, enty of foeign matte, beaing mounting eo, excessive deflection of the shaft, o any combination of these. Thus, it is difficult to detemine the eal cause of some pematue failues. If all the conditions at that time of failue and pevious to the time of failue ae known, including the application, the opeating conditions, and envionment; then by studying the natue of the failue and its pobable causes, the possibility of simila futue failues can be educed. The most fequent types of beaing failue, along with thei causes and coective actions, ae listed in Table 1.1. Table 1.1 Causes and Countemeasues fo Beaing Failues Type of Failue Iegulaities Photo Pobable Causes Countemeasues Type of Failue Iegulaities Photo Pobable Causes Countemeasues Scoing Cacks Indentations Scoing o smeaing between the end face of the olles and guide ib. Cack in oute o inne ing. Cack in olling element o boken ib. Factue of cage. Indentation on aceway with the same spacing as olling element (Binelling). Indentations on aceway and olling elements. Inadequate lubication, incoect mounting and lage axial load. Excessive shock load, excessive intefeence in fitting, poo shaft cylindicity, impope sleeve tape, lage fillet adius, development of themal cacks and inceased flaking. Inceased flaking, shock applied to ib duing mounting o dopped duing handling. Abnomal loading on the cage due to incoect mounting. Impope lubication Shock load duing mounting o excessive load when not otating. Enty of foeign matte such as metallic paticle and git. Select pope lubicant and modify the mounting. Examine the loading conditions, modify the fit of beaing and sleeve, impove accuacy in machining shaft and sleeve, collect fillet adius (the fillet adius must be smalle than the beaing chambe). Use cae in mounting and handling a beaing. Coect mounting and examine the lubication method and lubicant. Use cae in handling the beaing. Clean the housing, impove the seals and use clean lubicant. Beaing Failue and Countemeasues Flaking Flaking on one side of the aceway of adial beaing. Flaking patten inclined elative to the aceway in adial ball beaings Flaking nea the edge of the aceway and olling suface in olle beaing. Flaking of aceway with same spacing as olling element. Abnomal axial load (sliding failue of fee-side beaing). Impope mounting, bending of shaft, inadequate centeing, inadequate toleances fo shaft and housing. Lage shock load duing mounting, usting while beaing is out of opeation fo polonged peiod, mounting flaws of cylindical olle beaings. When mounting the oute ing of fee-side beaings, it should be fitted loosely, to allow axial expansion of the shaft. Use cae in mounting and centeing, select a beaing with a lage cleaance, and coect the squaeness of shaft and housing shoulde. Use cae in mounting and apply a ust peventative when machine opeation is suspended fo a long time. Abnomal wea False binelling (phenomenon simila to binelling). Fetting, Localized wea with eddish-bown wea dust at fitting suface. Weaing on aceway, olling elements, ib and cage. Vibation of the beaing without otation when out of opeation, such as duing tanspot, o ocking motion of vibation. Sliding wea at a minute gap in the fitting suface. Enty of foeign matte, incoect lubication and ust. Secue the shaft and housing, use oil as a lubicant and educe vibation by applying peload. Incease intefeence and apply oil. Impove sealing capabilities, clean the housing and use a clean lubicant. Pematue flaking of aceway and olling element. Insufficient cleaance, excessive load, impope lubication, ust, etc. Select pope fit, beaing cleaance, and lubicant. Ceep, scoing wea at fitting suface. Insufficient intefeence, insufficiently secued sleeve. Modify the fitting and tighten the sleeve popely. Pematue flaking of combined beaings. Excessive peload. Adjust the peload. Seizue Discoloation and melting of aceway, olling elements and ibs. Insufficient cleaance, incoect lubication, o impope mounting. Examine the fitting and intenal cleaance of a beaing, supply an adequate amount of pope lubicant and examine the mounting method and quality of elated pats. Scoing Scoing o smeaing between aceway and olling suface. Inadequate initial lubication, excessively had gease, high acceleation when stating opeation. Use a softe gease and avoid apid acceleation. Coosion and Rust Coosion and ust at beaing inteio o fitting suface. Condensation of wate fom the ai, o fetting, enty of coosive substance (especially vanish gas). Stoe caefully when in a moist o hot climate, take ust pevention measues befoe emoving fom opeations fo a long time, and select pope vanish and gease

111 1. BEARING FAILURE and COUNTERMEASURES Pat 1 Pat 2 Pat 3 Pat 4 Pat 5 Pat 6 Pat7 Pat 8 Running Taces and Applied Loads Table 1.2 Appendix Beaing Diagnostic Chat (a) (b) (c) (d) Damage name Location (Phenomenon) Handling Stock, Shipping Mounting Beaing suounding Shaft, Housing Sealing device, wate, debis Tempeatue Typical Cause Lowbowcation Lubicant Lubication method Excessive load Load Moment load Too small load High speed, high accelaation Speed Oscillating, vibation, stationay Beaing selection Remaks Beaing Failue and Countemeasues Inne ing otation Radial load Oute ing otation Radial load Inne ing o oute ing otation Axial load in one diection Inne ing otation Radial and axial load 1. Flaking Raceway, Rolling suface (e) (f) (g) (h) 2. Peeling Raceway, Rolling contact suface Beaings oute diamete sufaces Mating olling pat 3. Scoing Rolle end suface, Rib suface Cage guide suface, Pocket suface 4. Smeaing Raceway, Rolling suface 5. Factue Raceway colla, Rolles Raceway ings, Rolling elements 6. Cacks Rib suface, Rolle end face, Cage guide suface (Themal cack) Inne ing otation Axial load and misalignment Inne ing otation Moment load (Misalignment) Inne ing otation Housing boe is oval Inne ing otation No adial intenal cleaance (Negative cleaance duing opeation) 7. Cage damage (Defomation), (Factue) (Wea) Fig. 1.1 Typical Running Taces of Deep Goove Ball Beaings (i) (j) (k) (l) (m) 8. Denting 9. Pitting 10. Wea 11. Fetting Raceway, Rolling suface, (Innumeable small dents) Raceway (Debis on the olling element pitch) Raceway, Rolling suface Raceway, Rolling suface, Rib suface, Rolle end face Raceway, Rolling suface Beaing outside and boe, side suface (Contact with housing and shaft) 12. False binelling Raceway, Rolling suface 13. Ceep Raceway, Rolling suface Loose fit Inne ing otation Radial load Inne ing otation Moment load (Misalignment) Inne ing otation Radial load Inne ing otation Axial load Inne ing otation Axial load and Moment load (Misalignment) 14. Seizue 15. Electical coosion Fitting suface Raceway, Rolling suface Electicity passing though the olling element Fig. 1.2 Typical Running Taces of Rolle Beaings 16. Rust and coosion 17. Mounting flaws 18. Discoloation Raceway ing, Rolling element, Cage Raceway, Rolling suface Raceway ing, Rolling element, Cage Remak: This table is not compehensive. It lists only the moe commonly occuing damages, causes, and locations

112 2. DIAGNOSIS with SOUND and VIBRATION Pat 1 Pat 2 Pat 3 Pat 4 Pat 5 Pat 6 Pat7 Pat 8 Classification of sounds and vibations Sound and vibation accompany the otation of olling beaings. The tone and amplitude of such sound and vibation vay depending on the type of beaing, mounting conditions, opeational conditions, etc. The sound and vibation of a olling beaing can be classified unde the following fou chief categoies and each categoy can be futhe classified into seveal sub-categoies, as descibed in Table 2.1 below. Boundaies between goups ae, howeve, not definite. Even if some types of sounds o vibations ae inheent in the beaings, the volume might be elated to the manufactuing pocess, while some types of sounds o vibations, even if they aise due to manufactuing, Table 2.1 Classification of sounds and vibations in a olling beaing cannot be eliminated even in nomal conditions. By ecoding sounds and vibations of a otating machine and analyzing them, it is possible to infe the cause. As can be seen fom figues on the next page, a mechanically nomal beaing shows a stable wavefom. Howeve, a beaing with a scatch, fo example, shows a wavefom with wide swings indicating lage-amplitude sounds at egula intevals. NSK poduces Beaing Monito NB-4, a vibation measuing monito that can diagnose iegulaities in a otating machine, and the causes of the iegulaities can be infeed using the NB-4 and ecoding equipment, such as a pesonal compute. Sound wavefom of a nomal beaing Sound wavefom of a scatched beaing Geneated fequency (fequency analysis) sound Vibation Featues FFT of oiginal wave FFT afte Souce envelope Radial (angula) diection Axial diection (basic No.) Vibation Measuing Equipment, Beaing Monito NB-4 (See Page 128) Countemeasues Diagnosis with Sound and Vibation Race noise Fee vibation of aceway ing Continuous noise, basic unavoidable noise which all beaings geneate f RiN, f Ml f AiN, f AM Selective esonance of waviness (olling fiction) Impove igidity aound the beaings, appopiate adial cleaance, high-viscosity lubicant, high-quality beaings Click noise Fee vibation of aceway ing, fee vibation of cage Regula noise at a cetain inteval, lage beaings and hoizontal shaft, adial load and low pm f RiN, f Ml f AiN, f AM Natual fequency of cage Zf c Collision of olling elements with inne ing o cage Reduce adial cleaance, apply peload, high-viscosity oil Stuctual Squeal noise Fee vibation of aceway ing Intemittent o continuous, mostly lage cylindical olle beaings, adial load, gease lubication, at paticula speed CK noise Fee vibation of cage Regula noise at a cetain inteval, all beaing types geneate it ( f R2N, f R3N ) Natual fequency of cage? f c Self-induced vibation caused by sliding fiction at olling suface Collision of cage with olling elements o ings Reduce adial cleaance, apply peload, change the gease, eplace with countemeasued beaings Apply peload, high-viscosity lubicant, educe mounting eo Cage noise CG noise Vibation of cage Intemittent o continuous, lubication with paticula gease Natual fequency of cage? Self-induced vibation caused by fiction at cage guide suface Change of gease band, eplace with countemeasued cage Tapping noise Fee vibation of cage Cetain inteval, but a little iegula unde adial load and duing initial stage Natual fequency of cage Zf c Collision of cage and olling element caused by gease esistance Reduce adial cleaance, apply peload, low-viscosity lubicant Rolling element passage vibation Continuous, all beaing types unde adial load Zf c Displacement of inne ing due to olling element passage Reduce adial cleaance, apply peload Manufactuing Waviness noise Vibation due to waviness Inne ing Oute ing Continuous noise Continuous noise nzf ± f i (nz ± 1 peaks) nzf c (nz ± 1 peaks) nzf i (nz peaks) nzf c (nz peaks) Inne ing aceway waviness, iegulaity of shaft exteio Oute ing aceway waviness, iegula boe of housing High-quality beaings, impove shaft accuacy High-quality beaings, impove housing boe accuacy Rolling element Continuous with olles, occasional with balls 2nf b ± f c (2n peaks) 2nf b (2n peaks) Rolling element waviness High-quality beaings Handling Flaw noise Vibation due to flaw Inne ing Oute ing Rolling element Regula noise at a cetain inteval f RiN, f Ml f AiN, f AM Zf i Zf c 2f b Nicks, dents, ust, flaking on inne ing aceway Nicks, dents, ust, flaking on inne ing aceway Nicks, dents, ust, flaking on olling elements Replacement and caeful beaing handling Replacement and caeful beaing handling Replacement and caeful beaing handling Contamination noise Vibation due to contamination Iegula f RiN, f Ml f AiN, f AM Iegula Enty of dit and debis Washing, impove sealing Seal noise Fee vibation of a seal Contact seal Natual fequency of seal ( f ) Self-induced vibation due to fiction at seal contact aea Change the seal, change the gease Lubicant noise Iegula?? Iegula Lubicant o lubicant bubbles cushed between olling elements and aceways Change the gease Othes f Continuous f Iegula inne ing coss-section High-quality beaings Runout f c f 2f c Continuous Continuous f c f 2f c Ball vaiation in beaing, olling elements non-equidistant Non-linea vibation due to igid vaiation by ball vaiation High-quality beaings High-quality beaings

113 2. DIAGNOSIS with SOUND and VIBRATION Pat 1 Pat 2 Pat 3 Pat 4 Pat 5 Pat 6 Pat7 Pat 8 How to ecod sound and vibation wavefoms Though fequency analyses of sound o vibation of a otating machine, it is possible to infe the cause of abnomal vibation. We will descibe hee how to ecod vibations using Beaing Monito NB-4 (see Page 128) and how to ecod sounds using a micophone. Sounds and vibations should be ecoded unde both nomal and abnomal conditions, to detemine the cause of iegulaities. How to ecod vibations when ecoding the wavefom diectly by a compute Requied equipment: Beaing Monito NB-4 Pesonal compute (with line-input teminal and wavefom ecoding softwae) Monophonic cable fo wavefom date ecoding (3.5 pin jack at one end) Fig. 2.1 Configuation fo ecoding sound and vibation wavefoms Stat ecoding vibation wavefom data using audio ecoding softwae. Adjust ecoding level of the pesonal compute to Micophone NB-4 Rotating machine Pick-up cable (NB-4 accessoy) Pick-up cable Connect the pick-up cable to Beaing Monito NB-4 and then attach the pick-up teminal to the machine to be measued. To measue vibation, it is best to attach the pick-up teminal to a spot nea a beaing in the machine. maintain input signals within a given ange. Recoding fo at least 20 seconds is ecommended. Save ecoded vibation wavefom data. (Be awae that some vibation data may be lost depending on the file fomat.) Analyze ecoded vibation wavefom data to check fo Diagnosis with Sound and Vibation AC-OUT monophonic cable Analysis via data ecode iegula vibation. 3.5 pin jack Pesonal compute AC-OUT 2 Envelope analysis Diect analysis via compute Line input Damage in the aceway suface o olling element may poduce impact vibation at egula intevals. In this case, FFT analysis of vibation wavefoms cannot detect the fequency Pesonal compute components geneated by the damage. Unde these cicumstances, envelope analysis, which gives envelope delay Input by micophone BNC, etc. FFT analyze Connect NB-4 (AC-OUT) and ecoding equipment (in the left pictue, the micophone input of a pesonal compute 1 ) using a monophonic cable (3.5 pin-jack at NB-4 side). 1 A micophone input teminal can be used as a substitute, although depending on the magnitude of vibation, it may not distotion to oiginal wavefoms to analyze fequencies, can detect these fequency components.fo envelope analysis, equipment needs to have an envelope pocessing function. (a) T (b) T Data ecode be able to handle input that falls outside of a given ange. Time Time Line input Fequency analysis (t) Envelope delay distotion Fequency analysis (t) Cautions fo ecoding sound and vibation wavefoms Analyzing data afte ecoding is easy povided the following pecautions ae taken. Fequency 1/T 2/T Fequency 1) Stop opeation of neaby machines to cut off ambient noise and vibation. 2) Collect sound and vibation data unde both nomal and abnomal conditions. 3) Listen to a playback of ecoded sounds to check fo iegulaities. Recoding of otating vibations (NORMAL) Recoding of vibations caused by a scatch inside a beaing (ENVELOPE) Set NB-4 to ACC-NORMAL when measuing otation vibations Fequency spectum of (a) (t) Fequency spectum of (b) (t) 4) Collect sound and vibation data while changing the numbe of otations of the machine (fo example, 100 min 1, 800 min 1, and of a machine. Set NB-4 to ACC-ENVELOPE (envelope analysis 2 ) min 1 ). when measuing vibations due to a scatch inside a beaing

114 2. DIAGNOSIS with SOUND and VIBRATION Pat 1 Pat 2 Pat 3 Pat 4 Pat 5 Pat 6 Pat7 Pat 8 How to ecod sounds when ecoding diectly by a compute Requied equipment: Micophone fo measuing sound Pesonal compute (equipped with a micophone input teminal and audio ecoding softwae) Sounds ecoded in this way and saved as a WAV file can be fequency-analyzed by using commecially available FFT softwae. Vibation o sound fequencies associated with damage such as scatching o waviness on the beaing aceway suface can be obtained as seen in Fig 2.4. When these fequency components ae found as a esult of fequency analysis conducted with FFT softwae, the beaing suface may be damaged. Upon equest, NSK will be able to analyze sounds stoed as a WAV file. When such a equest is made, NSK will need ecoded sounds unde both nomal and abnomal conditions. Note that fequency analysis of sounds and vibation wavefoms of a otating machine may not be possible (Note that fequency analysis of sounds and vibation wavefoms of a otating machine may not be possible) when the ecoding conditions ae not sufficiently fulfilled. Connect a micophone to ecoding equipment. We ecommend a micophone with fequency chaacteistics 3 that effectively ecod the sounds of a machine. A micophone fo measuing sound should be used because a micophone built into a pesonal compute is suitable fo ecoding human voices but is often not appopiate fo ecoding the sounds of a machine. Keep the micophone at an appopiate distance fom the otating machine being inspected. (If too close, sounds of entangled ai will be ecoded, and if too distant, sound level will be too low.) It is ecommended to stop opeation of neaby machines to cut off the ambient noise, which makes it difficult to analyze ecoded noise. Use a unidiectional micophone, if available, to cut off ambient noises. Fig. 2.4 Examples of Results of Sound and Vibation Fequency Analysis Conducted with FFT Softwae When thee is damage on an oute-ing aceway suface Boe diamete: 160 mm Recoding and analysis method: FFT analysis esult of ACC-ENVELOPE output of Beaing Monito NB-4 Numbe of otations: min 1 Fequency components of damage on oute ing (zfc) Diagnosis with Sound and Vibation 3 Micophone fequency chaacteistics Fequency chaacteistics vay by type of micophone. Fo example, at 60Hz o less, the micophone (see Fig. 2.2) exhibits low sensitivity while the othe micophone (see Fig. 2.3) exhibits stable chaacteistics fo maintaining good sensitivity acoss a wide ange of fequency bands. Theefoe, the micophone Fig. 2.3 is suitable fo measuing sounds of a machine due to its stable chaacteistics acoss a wide ange of fequency bands. Fig. 2.2 Stat ecoding with ecoding equipment. Adjust ecoding level of the pesonal compute to maintain input signals within a given ange. Save ecoded sound data. (Be awae that some vibation data may be lost depending on the file fomat.) Hz When thee is damage on an inne-ing aceway suface Boe diamete: 100 mm Recoding and analysis method: Envelope analysis esult of sounds of a test machine ecoded by a micophone Numbe of otations: 50 min 1 Fequency components of damage on inne ing (zfi) Sensitivity Fig K Fequency 2K 5K 10K 20K Listen to a playback of ecoded sounds to check fo iegula noise Hz When thee is a significant imbalance in the main shaft Boe diamete: 65 mm Recoding and analysis method: FFT analysis esult of sounds of a test machine ecoded by a micophone Numbe of otations: min An integal multiple of fequency components of main-shaft otations (f n) Sensitivity K Fequency 2K 5K 10K 20K Hz