Roller Bearings for Machine Tools. Precision Ball & Roller Bearings for Machine Tools

Transcription

1 Rolle Beaings fo Machine Tools Pecision Ball & Rolle Beaings fo Machine Tools

2 Pecision Ball & Rolle Beaings fo Machine Tools CAT. NO. B2005E-1

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4 Catalog Pecision Ball & Rolle Beaings fo Machine Tools Peface Thank you fo you valuable suppot of KOYO poducts. Nowadays, thee is a pessing demand in the industial wold fo sophisticating machine tools in all aspects. Accodingly, ball & olle beaings fo machine tools must be moe compact and lightweight and exhibit such featues as longe sevice life, highe pefomance, and highe eliability. This is made possible only though a wide ange of high technologies. Unde these cicumstances, we have decided to publish this evised vesion of the KOYO catalog, Pecision Ball & Rolle Beaings fo Machine Tools. In this catalog, we have eniched the contents and added new poducts. We ae confident that this catalog will be of help to the use in the design of machine tools and in the use of pecision olling beaings. JTEKT continually offes the best technologies, quality, and sevices, though inspiation fom the maket and putting effots into eseach and technical developments. We hope that you will be as satisfied with ou poducts and sevices as you have been in the past. The contents of this catalog ae subject to change without pio notice. Evey possible effot has been made to ensue that the data listed in this catalogue is coect. Howeve, we can not assume esponsibility fony eos o omissions. Repoduction of this catalog without JTEKT's pemission is stictly pohibited.

5 CONTENTS I. Pecision Ball & Rolle Beaings Technical Desciptions 1. Types and stuctues of pecision ball & olle beaings fo machine tools Selection of beaings Selection of beaing types Spindle beaing aangements Sevice life of beaings 5. 1 Rating life of beaings Sevice life calculation of beaings Dynamic equivalent loads Basic static load ating and static equivalent load Sevice life of geases Pemissible axial loads Rigidity and peload of beaings 6. 1 Rigidity of beaings Peload of beaings Limiting speeds of beaings Lubication 8. 1 Gease lubication Oil lubication Designing peipheal pats of beaings 9. 1 Toleances of shafts and housings Limits of chamfe dimensions and fillet adii of shafts and housings Spaces fo oil / ai lubication High Ability angula contact ball beaings Ceamic beaings fo machine tool spindles 45 Beaing Dimension Tables 1. Angula Contact Ball Beaings 1. 1 Types and featues of angula contact ball beaings Matched paingula contact ball beaings Composition of beaing numbes Toleance of beaings Standad peloads fo matched pai angula contact ball beaings Axial load and displacement 60 (Beaing Dimension Tables) Cylindical Rolle Beaings 2. 1 Types and featues of cylindical olle beaings Composition of beaing numbes Toleance of cylindical olle beaings Radial intenal cleaances of cylindical olle beaings 125 (Beaing Dimension Tables) Angula Contact Ball Beaings fo Axial Load 3. 1 Types and featues of angula contact ball beaings foxial load Composition of beaing numbes Toleance of angula contact ball beaings foxial load Standad peloads fo high-speed matched paingula contact ball beaings Axial load and displacement 143 (Beaing Dimension Tables) 146 4

6 II. Oil / Ai Lubication System 4. Tapeed Rolle Beaings 4. 1 Types and featues of tapeed olle beaings Composition of beaing numbes Toleance of tapeed olle beaings Axial load and displacement 159 (Beaing Dimension Tables) Suppot Beaings and Suppot Beaing Units fo Pecision Ball Scews 5. 1 Stuctue and featues Composition of identification numbes Toleance of suppot beaings fo pecision ball scews Axial load and displacement 174 (Beaing and Beaing Unit Dimension Tables) Oil / ai lubicato Ai cleaning unit 188 III. Handling of Beaings 1. Handling and mounting of beaings 192 IV. Examples of Beaing Failues 1. Beaing failues, causes and countemeasues 204 V. Supplementay Tables 1. Shaft toleances Housing boe toleances Numeical values fo standad toleance gades IT Steel hadness convesion SI units and convesion factos Lubication (dischage) intevals of the oil / ai Specification epot 220 5

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8 I. Pecision Ball & Rolle Beaings

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10 CONTENTS Technical Desciptions I. Pecision Ball & Rolle Beaings 1. Types and stuctues of pecision ball & olle beaings fo machine tools Selection of beaings Selection of beaing types Spindle beaing aangements Sevice life of beaings 5. 1 Rating life of beaings Sevice life calculation of beaings Dynamic equivalent loads Basic static load ating and static equivalent load Sevice life of geases Pemissible axial loads Rigidity and peload of beaings 6. 1 Rigidity of beaings Peload of beaings Limiting speeds of beaings Lubication 8. 1 Gease lubication Oil lubication Designing peipheal pats of beaings 9. 1 Toleances of shafts and housings Limits of chamfe dimensions and fillet adii of shafts and housings Spaces fo oil / ai lubication High Ability angula contact ball beaings Ceamic beaings fo machine tool spindles 45 9

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12 Pecision Ball & Rolle Beaings Technical Desciptions

13 I. Pecision Ball & Rolle Beaings 1. Types and stuctues of pecision ball & olle beaings fo machine tools Table 1. 1(1) Types and stuctues of pecision ball & olle beaings fo machine tools z Spindle beaings Beaing types Coss-sections Beaing seies Angula contact ball beaings Standad types High-speed types Ultahigh-speed types 79C 70C 72C CPA 70CPA 72CPA HAR9C HAR0C HAR9CA HAR0CA HAR9 HAR0 3NCHAC9C 3NCHAC0C 3NCHAC9CA 3NCHAC0CA Contact angles NCHAD0CA 20 3NCHAF9CA 3NCHAF0CA 20 Featues and desciptions Some beaing seies suppot contact angle of 40 (B). Exhibits supeb high-speed pefomance using an oute ing guided cage. Impovements in high-speed pefomance ae made though the use of balls that have a smalle diamete than standad beaing balls. Also, a lage numbe of balls contibutes to highe igidity. Rolling elements ae available in steel and in ceamic. Consult JTEKT, as the HAR000 seies can coespond to the non-contact seal. Lage-diamete balls enable high load-caying capacity. Ceamic balls ealize excellent high-speed pefomance. These beaings have holes fo oil / ai lubication. They ae suitable fo ultahigh-speed applications. Ceamic balls ealize excellent high-speed pefomance. Page No NN-type double ow cylindical olle beaings NNU-type double ow cylindical olle beaings NN30 NN30K NNU49 NNU49K ---- Beaings with tapeed boes (K) ae also available fopplications using tapeed shafts. Fo adial intenal cleaance values, use non-intechangeable beaings. Beaings povided with a lubication hole o goove on the oute ing ae also available (W) Beaings with tapeed boes (K) ae also available fopplications using tapeed shafts. 121 N-type single ow cylindical olle beaings N10 N10K ---- Fo adial intenal cleaance values, use non-intechangeable beaings. This type of beaing poduces less heat and has bette highspeed pefomance than double ow cylindical olle beaings. 12

14 Table 1. 1(2) Types and stuctues of pecision ball & olle beaings fo machine tools Beaing types Coss-sections Beaing seies Contact angles Featues and desciptions Page No. 2344B 2347B 60 Placed on the small tapeedboe diamete side of NN30K, o used togethe with NN30. Placed on the lage tapeed-boe diamete side of NN30K. Double-diection angula contact thust ball beaings 2394B 2397B 60 Placed on the small tapeedboe diamete side of NNU49K, o used togethe with NNU49. Placed on the lage tapeed-boe diamete side of NNU49K. 135 High-speed pai-mounted angula contact ball beaings ACT0DB 30 ACT0BDB 40 High-speed beaings of the same boe and outside diametes as double-diection angula contact thust ball beaings 2344B. They ae placed on the small tapeed-boe diamete side of NN30K. Tapeed olle beaings 329JR 320JR 302JR 322JR Nominal contact angles: geate than 10 and equal to o less than 17 Metic seies single ow tapeed olle beaings complying with ISO standads. 155 x Suppot beaings and suppot beaing units fo pecision ball scews Beaing types Coss-sections Beaing seies Contact angles Featues and desciptions Page No. Standad peloads ae specified, espectively, fo 2-, 3-, and 4- ow matched beaings. Flush-gound G-type beaings ae also available. Suppot beaings fo pecision ball scews Both-side sealed type Matching example of one-side sealed type SAC 60 The suppot beaing fo pecision ball scews can coespond to the type with contact-seal. Consult JTEKT if desiing infomation about the type with seal and the matching method. 169 BSU (60 ) Suppot beaing units consist of a suppot beaing fo pecision ball scews (SAC) and a pecision housing. Suppot beaing units fo pecision ball scews Fitting this beaing unit is vey simple. 13

15 I. Pecision Ball & Rolle Beaings 2. Selection of beaings In ode to select the optimum beaing to ealize the intended design of a machine, it is necessay to conside specific opeating conditions of the machine, beaing equiements, designs of pats aound the beaing, maketability, and cost pefomance. Table 2. 1 specifies the geneal pocedue fo selecting a beaing, and opeating conditions to be taken into consideation. Note, howeve, that when selecting a beaing, pioity should be given to meeting the most citical equiement athe than following a given pocedue. Table 2. 1 Pocedue fo selecting beaings and opeating conditions to be taken into consideation Selection pocedue Opeating condition to be taken into consideation Related infomation on beaings Page No. q Beaing types and aangements w Beaing dimensions e Beaing toleance class Installation space Magnitude, diection, and types of load applied to beaings Rotational speeds Running accuacy Noise/fictional toque Rigidity Method of mounting and dismounting Beaing aangements Maketability and cost pefomance Dimensions of beaing mounting positions Dynamic equivalent load and ating life Rotational speeds Running accuacy (unout) Noise/fictional toque Rotational speeds Beaing types 15 Beaing aangement examples 16 Beaing ating life 18 Basic dynamic load atings 18 Dynamic equivalent loads 20 Pemissible axial loads 24 Beaing toleances (Dimension tables) Fitting and intenal cleaance t Type and mateial of cage Loading condition Opeational tempeatue distibution Fitting Shaft and housing mateials Dimensions and toleances Tempeatue diffeences between inne ing and oute ing Rotational speed Amount of peload Rotational speeds Noise Lubication methods Recommended fitting 28 Running accuacy of shafts and housings 35 Beaing peload 25 Intenal cleaance Dimension of beaings tables y Lubication method, lubicant, and sealing device Opeating tempeatues Rotational speeds Sealing device Lubication methods Lubicants Limiting speeds of beaings 30 Lubication of beaings 31 u Method of mounting and dismounting, and mounting dimensions Method of mounting and dismounting Handling of beaings 192 Decision on final specifications of beaing and pats aound beaing If you wish to consult JTEKT about specifications, fill out the supplementay table 7 "Specification epot of beaing fo main shaft of machine tool" on page 220, and contact JTEKT. 14

16 3. Selection of beaing types When selecting a beaing type, it is of citical impotance to fully undestand the opeating conditions of the beaing. Table 3. 1 shows pincipal items to be consideed and how to select a beaing type. Table 3. 1 Selection of beaing types Items to be consideed q Installation space Beaing can be installed in taget equipment w Load Load magnitude, type and dieciton which applied The load capacity of the beaing is expessed in tems of the basic load ating, the value of which is given in the beaing dimension tables. e Rotational speeds Beaing types compatible with the machine's opeating speed Standad values fo otational speed limits of beaings ae expessed in limiting speed given in the beaing dimension tables. Running accuacy Beaing types meeting equiements fo unning accuacy Dimension and unning accuacies ae standadized by JIS and the like fo each beaing type. t Rigidity Beaing types meeting the igidity equiements fo machine shaft systems When a load is applied to a beaing, elastic defomation occus at the contacts between the aceway and olling elements.the smalle the elastic defomation, the highe the igidity. y Mounting and dismounting Beaing types should be selected taking into consideation the fequency and method of mounting and dismounting on occasions such as peiodic inspection How to select a type When designing a shaft system, citical factos on the whole ae shaft igidity and stength, theefoe, shaft diamete, namely, the boe diamete of the beaing is detemined fist. The installation space detemined by types and the dimension seies of the beaings used fo the spindles of machine tools ae shown in Fig Select the optimum beaing fom the types illustated. Select the optimum beaing type taking into consideation the magnitude of the load applied to the beaing, whethe the load is axial o adial, whethe, in the case of axial load, the load is unidiectional o bidiectional, the level of vibation and shock, and othe elevant factos. Radial load capacity vaies as shown below with the boe diamete emaining the same. (Small) (Lage) Angula contact ball beaings Cylindical olle beaings Tapeed olle beaings Limiting speeds of beaings lagely depends not only on the beaing type, but also on othe factos such as beaing size, unning accuacy, type and mateials of the cage, magnitude of load, and lubication. Select a beaing taking these fully into consideation. In geneal, angula contact ball beaings and cylindical olle beaings ae often used fo high-speed applications. The spindles of machine tools, which need to otate with high accuacy, equie pecision beaings meeting toleance class 5 o bette. In geneal, angula contact ball beaings and cylindical olle beaings ae used. In ode to impove the machining pecision of a machine tool, the igidity of beaings as well as the igidity of the shaft should be impoved. In geneal, olle beaings exhibit a high igidity, while ball beaings exhibit low igidity. Beaings of the same type and dimensions vay in igidity with the numbe of olling elements and contact angle. The igidity of a beaing is inceased by applying a peload to the beaing (to povide a cleaance of a negative value). This method is suitable fongula contact ball beaings and tapeed olle beaings. If the beaing is to be mounted and dismounted fequently, cylindical olle beaings and tapeed olle beaings ae advantageous, as the inne ing and oute ing ae sepaable. 79 seies HA9 seies NNU49 seies 2394 seies 70 seies HA0 seies ACT0 seies N10 seies NN30 seies 2344 seies 320 seies Fig Installation space detemined by types and dimension seies of pecision olling beaings fo machine tools 15

17 I. Pecision Ball & Rolle Beaings 4. Spindle beaing aangements Table 4. 1 pesents typical aangements fo spindle beaings fo machine tools. Fo high-speed spindles, the use of ceamic beaings enables highe speed. Types 1 2 High igidity Table 4. 1(1) Examples of spindle beaing aangements (The d mn value epesents the poduct of the pitch diamete of ball set d m and the otational speed n.) Pincipal Spindle beaing aangements Featues applications (Font) Single ow tapeed olle beaing 320JR (Rea) Double ow cylindical olle beaing NN30K Gease lubication d mn value Both adial and axial loads ae accepted by the tapeed olle beaing. This aangement poduces high igidity but is not suitable fo high speed opeation. In some cases, a double ow tapeed olle beaing 46C o 46T is used in the font. 46C : two single ow beaings combined in an outwad aangement 46T : a double cup and two single ow of cones constituting an outwad aangement (Font) (Rea) In this stuctue, adial load is accepted by a double ow cylindical olle beaing and axial load is accepted by a double-diection angula contact thust ball beaing. This aangement poduces Double ow Double ow high igidity. cylindical olle beaing cylindical olle beaing NN30 NN30K Double-diection angula contact thust ball beaings 2344B Gease lubication d mn value Lage lathes Genealpupose lathes Milling machines CNC lathes Machining centes Boing machines Milling machines 3 (Font) (Rea) A high-speed matched pai angula contact ball beaing is used instead of the doublediection angula contact thust ball beaing in Type 2. Contact angles of the highspeed pai-mounted angula contact ball beaings ae 30 Double ow Double ow fo ACT0DB and 40 fo cylindical olle beaing cylindical olle beaing ACT0BDB. NN30K NN30K High-speed pai-mounted angula contact ball beaings ACT0DB o ACT0BDB Gease lubication d mn value CNC lathes Machining centes Milling machines 4 High-speed (Font) Standad angula contact ball beaing 70C (Rea) Double ow cylindical olle beaing NN30K Both adial and axial loads ae accepted by the angula contact ball beaing. This aangement is supeio to Type 3 in high-speed pefomance, but infeio in adial and axial igidity. CNC lathes Machining centes Milling machines Gease lubication d mn value Oil / ai lubication

18 Table 4. 1(2) Examples of spindle beaing aangements Types Spindle beaing aangements Featues Pincipal applications (Font) (Rea) The font beaing of Type 4 is conveted to a high-speed type. CNC lathes Machining centes 5 High-speed High-speed angula contact ball beaing HAR0C Double ow cylindical olle beaing NN30K Milling machines Gease lubication d mn value Oil / ai lubication (Font) (Rea) High-speed angula contact ball beaings ae used in both the font and ea to povide geate high-speed pefomance. Boing machines Machining centes 6 7 High-speed/high-pecision High-speed angula contact ball beaing HAR0C Gease lubication d mn value Oil / ai lubication (Font) (Rea) Standad angula contact ball beaing o high-speed angula contact ball beaing 70C HAR0C Factos such as themal expansion should be taken into consideation fo peload settings. Constant-pessue peloading is used to pevent incease in peload due to heat. This aangement poduces a lowe igidity than that poduced by position peloading, but is supeio in high-speed pefomance. Ginding machines Gease lubication d mn value Oil / ai lubication (Font) (Rea) A high-fequency moto is built in Types 4 to 6. Machining centes 8 Built-in moto High-speed angula Single ow contact ball beaing cylindical olle beaing HAR0C NU10K Oil / ai lubication d mn value Since the diving system consisting of belts, geas, couplings, etc. can be omitted, this aangement saves space and educes vibation. The high-speed angula contact ball beaing is used in the font, and the single-ow cylindical olle beaing is used in the ea. 17

19 I. Pecision Ball & Rolle Beaings 5. Sevice life of beaings 5. 1 Rating life of beaings 5. 2 Sevice life calculation of beaings When a beaing otates unde load, the sufaces of the innend oute ing aceways and the sufaces of the olling elements ae constantly subjected to epetitive loads. Even unde pope opeating conditions this esults in scale-like damage (known as flaking) of the sufaces due to fatigue. The total numbe of otations befoe this damage occus is known as "(fatigue) sevice life" of the beaing. A substantial vaiation in "(fatigue) sevice life" occus even if beaings of the same stuctue, dimensions, mateials, machining method, etc. ae opeated unde the same conditions. This vaiation in fatigue, an intinsic phenomenon to the mateial, should be examined statistically. The total numbe of otations at which 90% of the same type of beaings individually opeated unde the same conditions ae fee of damage caused by olling fatigue (in othe wods, sevice life of 90% eliability), is efeed to as "basic ating life of the beaing." In some cases, howeve, beaings, when actually mounted and opeated on a machine, may become inopeative due to causes othe than damage by fatigue (wea, seizue, ceep, fetting, binelling, cacking, etc.). By giving sufficient consideation to the selection of beaings, installation, lubication, and the like, it is possible to avoid such causes Basic dynamic load atings The stength of a beaing against olling fatigue---- that is, the basic dynamic load ating epesenting the beaing load capacity----is the net adial load (in the case of a adial beaing) o cental axial load (in the case of a thust beaing) such that its magnitude and diection ae constant and the beaing can attain a basic ating life of 1 million otations unde the condition that the inne ing otates while the oute ing is stationay (o vice vesa). These ae called "basic dynamic adial load ating (C )" o "basic dynamic axial load ating (C a)," espectively. Values fo these items ae given in the beaing dimension tables Basic ating life The elationship among the basic dynamic load ating, the dynamic equivalent load, and the basic ating life is expessed by equation (5. 1). If a beaing is to be opeated at a constant otational speed, its sevice life is conveniently expessed in hous as detemined by equation (5. 2). (Total numbe of otations) C L 10= ( p (5. 1) P) 10 6 C (Hous) L 10h= p (5. 2) 60n P ( ) whee, L 10 : basic ating life 10 6 otations L 10h : basic ating life h P : dynamic equivalent load N C : basic dynamic load ating N n : otational speed min 1 p : p=3 fo ball beaings p=10/3 fo olle beaings When a beaing is opeated with a dynamic equivalent load of P and a otational speed of n, the basic dynamic load ating C of the beaing, which is suitable fo meeting the design sevice life, is given by equation (5. 3). Thus the beaing dimensions ae detemined by selecting a beaing fom the beaing dimension tables, which meets equiement C. C=P 60n 1/p ( L10h ) (5. 3)

20 [ Refeence ] A method fo detemining the ating life of a beaing in a simplified method A fomula fo detemining sevice life, in which a sevice life coefficient (ƒ h) and speed coefficient (ƒ n) ae applied in equation (5. 2), is shown below. p L 10h=500 ƒ h (5. 4) Sevice life coefficient : C ƒ h=ƒ n (5. 5) P Speed coefficient : /p ƒ n= n ( ) =(0.03n) 1/p (5. 6) Values of ƒ n, ƒ h, and L 10h ae appoximated by the nomogams shown in Fig How to use nomogams Opeating conditions (example) Cylindical olle beaing NN3014K C=96.9 kn Rotational speed n=7 000 min 1 Dynamic equivalent load P=4.9 kn q Speed coefficient : Since n=7 000 ƒ n eads: ƒ n=0.2 w Sevice life coefficient : ƒ h is obtained as follows. C 96.9 ƒ h=ƒ n =0.2 =3.96 P 4.9 e Rating life : Since ƒ h=3.96, L 10h is: L 10h= Ball beaing Speed Sevice life Rolle beaing Speed Sevice life Fig Rotational speed (n) vs. speed coefficient (ƒ n ) and sevice life coefficient (ƒ h ) vs. sevice life (L 10h) 19

21 I. Pecision Ball & Rolle Beaings 5. 3 Dynamic equivalent loads Beaings ae used unde diffeent conditions. Fo example, they ae often subjected to a esultant load consisting of adial and axial loads, the magnitudes of which may vay. Consequently, it is not possible to diectly compae the actual load that a beaing eceives and the basic dynamic load ating. In such a case, a calculation is caied out fo compaison and examination, in which a load having a constant magnitude and diection, is applied to the beaing cente such that it would make the sevice life of the beaing the same as that esulting fom the actual load and otational speed. This theoetical load is known as the dynamic equivalent load (P). 2) Application of a adial load to a single ow angula contact ball beaing, o tapeed olle beaing, poduces a component of foce (F ac) in the axial diection (Fig. 5. 2). Theefoe, a pai of beaings ae usually used to aange face-to-face o back-to-back. The component of foce in the axial diection is detemined by the following equation. F F ac= (5. 8) 2Y Calculation of dynamic equivalent load The dynamic equivalent loads of a adial beaing and a thust beaing (α 90 ) eceiving a esultant load constant in magnitude and diection is obtained as illustated below. α F ac F Load cente α F ac F Load cente P=XF +YF a (5. 7) whee, P : dynamic equivalent load N Fo adial beaings, "P : dynamic equivalent adial load" and fo thust beaings, "P a : dynamic equivalent axial load," espectively, ae used. F : adial load N F a : axial load N X : adial load coefficient Y : axial load coefficient ( Values of X and Y ae noted in the beaing dimension tables. ) Dimensions epesenting the position of load centee noted in the beaing dimension tables. Fig Components of foce in axial diection Table 5. 1 (page 21) shows ways of detemining the dynamic equivalent load whee a adial load and extenal axial load (K a) ae applied to these beaings. 1) If F a/f e fo single ow adial beaing, X=1 and Y=0 ae used. Hence, the dynamic equivalent load will be P =F. e denotes the limit of F a/f, whose values ae listed in the beaing dimension tables. 20

22 Table 5. 1 Calculations of dynamic equivalent loads fo two opposing single ow angula contact ball beaings o tapeed olle beaings Beaing aangement Back-to-back Face-to-face Loading condition Beaing Axial load Dynamic equivalent load A B B A Beaing A F B 2Y B + Ka P A=XF A+Y A F ( B + K a ) 2Y B Note that P A= F A if P A< F A K a K a F B 2Y B F A + K a 2Y A F A F B F B F A Beaing B P B=F B A B B A Beaing A P A=F A F A K a F B F B K a F A F B 2Y B F A + K a < 2Y A Beaing B F A K a 2Y A P B=XF B+Y B F A ( K a ) 2Y A Note that P B=F B if P B<F B A B B A Beaing A P A=F A F A K a F B F B K a F A F B F A 2Y B 2Y A + K a Beaing B F A 2Y A + Ka P B=XF B+Y B F ( A + K a ) 2Y A Note that P B=F B if P B<F B A B B A Beaing A F B 2Y B K a P A=XF A+Y A F B ( K a ) 2Y B Note that P A=F A if P A<F A K a K a F B F A > + K a 2Y B 2Y A F A F B F B F A Beaing B P B=F B [ Remaks ] 1. These calculations ae applicable whee duing opeation the intenal cleaance and peload ae 0 (zeo). 2. Radial loads ae assumed to be positive even if they ae applied in the opposite diection of the aows shown above. 21

23 I. Pecision Ball & Rolle Beaings Mean dynamic equivalent loads fo vaiable loads When a load, applied to a beaing, vaies in magnitude and diection, it is necessay to obtain a mean dynamic equivalent load that may esult in the same sevice life as would esult undectual vaiation conditions. Ways of detemining the mean dynamic equivalent load P m suitable fo diffeent vaiation conditions ae shown in Table 5. 2, (1) to (4). In the case when a stationay load and a otational load ae applied simultaneously, as shown in (5), the mean dynamic equivalent load is given by equation (5. 13). Table 5. 2 Ways of detemining mean dynamic equivalent loads fom vaiable loads (1) Stepwise vaiation (2) Simple vaiation (3) Sine like cuve vaiation P P 1 P P P max P max P 2 Pm P m P m 0 P n 0 P min 0 n 1 t 1 n 2 t 2 n n t n Σ n i t i Σ n i t i Pm = p p p p P 1n 1 t 1 + P 2n 2 t P nn n t n n 1 t 1 + n 2 t n n t n (5. 9) P min+2p max P m= (5. 10) 3 P m=0.68p max (5. 11) Sine like cuve vaiation (4) Uppe potion of ( a sine cuve ) Stationay and otational (5) loads being applied at the same time 1.0 P P m P max P ƒm P u P/( P+P u ) Σ n i t i Fig ƒ m Coefficient P m=0.75p max (5. 12) P m=ƒ m (P +P u ) (5. 13) 22

24 In (1) to (4) in Table 5. 2: P m : mean dynamic equivalent load P 1 : dynamic equivalent load applied at a otational speed of n 1 fo t 1 hous P 2 : dynamic equivalent load applied at a otational speed of n 2 fo t 2 hous N N N specified as the basic static adial load ating, and fo thust beaings, as the basic static axial load ating. These load atings ae listed in the beaing specification table, using C 0nd C 0a espectively. These values ae pescibed by ISO 78/1987 and ae subject to change by confomance to the latest ISO standads. P n : dynamic equivalent load applied at a otational speed of n n fo t n hous P min : minimum dynamic equivalent load P max : maximum dynamic equivalent load Σn it i : total numbe of otations in a peiod fom t 1 to t i p : p=3 fo ball beaings p=10/3 fo olle beaings (Refeence) The mean otational speed n m is obtained by the following equation. n 1t 1+n 2t 2+ +n nt n n m= t 1+t 2+ +t n N N N Static equivalent load The static equivalent load is a theoetical load calculated such that, duing otation at vey low speed o when beaings ae stationay, the same contact stess as that imposed undectual loading condition is geneated at the contact cente between aceway and olling element to which the maximum load is applied. Fo adial beaings, adial load passing though the beaing cente is used fo the calculation; fo thust beaings, axial load in a diection along the beaing axis is used. The static equivalent load can be calculated using the following equations. In (5) in Table 5. 2: P m : mean dynamic equivalent load ƒ m : coefficient (see Fig. 5. 3) P : stationay load P u : otational load N N N [Radial beaings] The geate value obtained by the following two equations is used. P 0=X 0F +Y 0F a (5. 14) P 0=F (5. 15) 5. 4 Basic static load ating and static equivalent load Basic static load ating Excessive static load o impact load even at vey low otation causes patial pemanent defomation of the olling element and aceway contacting sufaces. This pemanent defomation inceases with the load; if it exceeds a cetain limit, smooth otation will be hindeed. The basic static load ating is the static load which esponds to the calculated contact stess shown below, at the contact cente between the aceway and olling elements which eceive the maximum load. Self-aligning ball beaings MPa Othe ball beaings MPa Rolle beaings MPa The total extent of contact stess-caused pemanent defomation on sufaces of olling elements and aceway will be appoximately times geate than the olling element diamete. The basic static load ating fo adial beaings is [Thust beaings] (α 90 ) P 0a=X 0F +F a (5. 16) [When F a<x 0F, the solution becomes less accuate.] (α=90 ) P 0a=F a (5. 17) whee, P 0 : static equivalent adial load P 0a : static equivalent axial load F : adial load F a : axial load X 0 : static adial load facto Y 0 : static axial load facto ( values of X 0 and Y 0 ae listed in beaing specification table. the) Safety coefficient N N N N The allowable static equivalent load fo beaing is detemined by the basic static load ating of the beaing; howeve, beaing sevice life, which is affected by pemanent defomation, diffes in accodance with the pefomance equied of the 23

25 I. Pecision Ball & Rolle Beaings beaing and opeating conditions. Theefoe, a safety coefficient is designated, based on empiical data, so as to ensue safety in elation to basic static load ating. C ƒ 0 s= (5. 18) P 0 whee, ƒ s : safety coefficient (ef. Table 5. 3) C 0 : basic static load ating P 0 : static equivalent load N N 5. 5 Sevice life of geases The pevious section explained the fatigue sevice life of beaings. Spindle beaings fo machine tools, howeve, aely have a poblem of beaing sevice life caused by load. When gease lubication is used, ineffective lubication may occasionally occu, esulting in beaing failues. It is theefoe necessay to give sufficient consideation to selecting the band and the amount of gease to be used, fo given opeating conditions. Refe to "8. Lubication of beaings" fo gease lubication. Table 5. 3 Values of safety coefficient ƒ s With beaing otation Without beaing otation occasional oscillation Opeating condition When high accuacy is equied ƒ s (min.) 2 3 Nomal opeation When impact load is applied When impact load o uneven distibution load is applied Nomal opeation [ Remak ] Fo spheical thust olle beaings, ƒ s 4. Ball beaing 1 Rolle beaing Pemissible axial loads A lage axial load may be applied to the beaings fo main shafts of machine tools when, fo example, tools ae changed. Application of a lage axial load to an angula contact ball beaing may cause the contact ellipse fomed between the ball and aceway suface to deviate beyond the aceway suface (see Fig. 5. 4). Futhemoe, if the stess becomes excessive, the olling elements and aceway suface may sustain pemanent defomation (nicks), possibly esulting in inceased unout o vibation. The smalle one of the following values is defined as the pemissible axial load (static). And the pemissible axial load (static) fo each beaing is shown in the dimension list of the beaings. The load geneated when the end of the contact ellipse fomed between the ball and the aceway eaches the shoulde of the inne o oute ing. The load geneated when the pessue of the contact suface between the ball and the aceway eaches the standad value calculated based on the actual esults. F a h 2a F a whee, h : beaing shoulde height a : half length of the contact ellipses' majoxis F a : axial load Fig Contact ellipse 24

26 6. Rigidity and peload of beaings 6. 1 Rigidity of beaings 6. 2 Peload of beaings The igidity of a beaing has a consideable influence on the igidity of the spindle of the machine tool. The igidity of a beaing can be impoved by the following methods. q Rolle beaings, in which line contact is made between the aceway suface and the olling element, ae used when a high adial igidity is equied. w In the case whee high axial igidity is equied, stack mounting angula contact ball beaings, ae geneally used. Futhemoe, beaings with a lage contact angle ae used. e Fo high-speed and high-igidity equiements, it is effective to educe the diametend incease the numbe of olling elements. It is also possible to impove the igidity of a beaing by using ceamics (silicon nitide) fo the olling elements which is supeio in Young's modulus. Beaings having ceamic olling elements also offe impoved high-speed pefomance since thei density is lowe than that of beaing steel, yielding a small centifugal foce even unde high-speed otation. Apply a peload to the beaing. Peloading means setting the inne cleaance to be a negative value and loading the beaing afte mounting it. In case of the angula contact ball beaing and tapeed olle beaing, an axial load is applied when peloading. And in case of the cylindical olle beaing, a adial load is applied when peloading Objective of peload To impove igidity To impove the positioning accuacy in the adial and axial diections, and to impove the unning accuacy as well, by minimizing the unout of the shaft To educe smeaing by contolling whil slip, obital slip, and otational slip of olling elements in highspeed otations To pevent noise caused by vibation and esonance Methods fo peloading Thee ae two majo methods fo peloading the angula contact ball beaing and tapeed olle beaing; position peloading and constant-pessue peloading. In the position peloading method, the beaing and space, whose dimensions ae adjusted to the specified values befoehand, ae used. In the constant-pessue peloading method, coil spings o disk spings ae used to peload the beaing. Usage examples and compaison of these methods ae shown in Fig Also, these peloading methods can be switched ove when otating, and the amount of the peload (load) can be gadually changed in accodance with the speed of the otation. Table 6. 1 Methods fo peloading Position peloading When applying the same peload, the displacement to load is smallend the igidity is highe than when using the constant-pessue peloading method. When otating at high speed, the use of this method is limited because the peload amount vaies depending on the mounting conditions, centifugal foce and tempeatue ise. Constant-pessue peloading This method is applicable when otating at high speed because thee is less peload vaiation when otating than when using the position peloading method, and almost constant peload can be maintained. Howeve, the impovement of the igidity of the shaft is not as good as when using the position peloading method. q A method using matched pai beaings with the peload adjusted. δ 0 δ 0 w A method using a space of peadjusted size. e A method using a nut o bolt capable of adjusting the amount of peload in the axial diection. (In this case, confim that the appopiate peload is applied while measuing the stating toque, etc. This method is not suitable fo conditions which equie high pecision, because the beaing tends to tilt easily. In these conditions, methods 1) and 2) ae ecommended.) A method using coil spings o disk spings to apply peload. When using the coil spings, place them on the cicumfeence at egula intevals so that the pessue is applied equally. 25

27 I. Pecision Ball & Rolle Beaings Peload and axial igidity Fig shows the elationship between peload (position peload) and igidity, namely, axial displacement of a back-to-back aangement beaing. Applying a peload P (by tightening the inne ing in the axial diection), as shown in Fig. 6. 1, esults in beaings A and B espectively being displaced by δ ao. The cleaance between the inne ings 2δ ao will then become 0 (zeo). When an extenal axial load T is applied to these beaings, thei esultant displacement as a paimounted beaing set can be obtained as δ a. [ Refeence ] How to detemine δ a in Fig q Obtain the displacement cuve of beaing A. w Obtain the displacement cuve of beaing B: this is the cuve symmetical with espect to the tansvese axis and the intesection x at the peload P. e Assuming an extenal load T, obtain a line x y on the tansvese axis passing though x. By paallel displacement of line x y along the displacement cuve of beaing B, the intesection y' passing though the displacement cuve of beaing A is obtained. δ a is detemined as the distance between the lines x' y' and x y. P : amount of peload T : extenal axial load T A : axial load applied to beaing A T B : axial load applied to beaing B δ a : displacement of paimounted beaing set δ aa : displacement of beaing A P T Beaing A δ ao Beaing B δao P Fig shows the elationship between peload and igidity when a constant-pessue peload is applied to the same pai-mounted beaing as shown in Fig Since the igidity of the sping is negligible in this case, the igidity of the beaing is appoximately equal to that of a single beaing given a peload P. Displacement in axial diection δ ab : displacement of beaing B T Displacement cuve of beaing A 2δ ao : cleaance between inne ings befoe applying peload δ aa δ a Axial load δ ao Displacement in axial diection P Displacement cuve of peloading sping T B T A T Displacement cuve of beaing A Fig Peload diagam of constant-pessue peloading δ ab δ ao δ aa x' x y' (T) y δ a Axial load Compaison of axial igidity of the position peloading and the constant-pessue peloading is shown in Fig δ ao P Displacement cuve of beaing B Single beaing Fig Peload diagam fo position peloading Deviation in axial diection Constant-pessue peloading Position peloading Extenal axial load Fig Compaison of axial igidity 26

28 Amount of peload If the amount of peload to the beaing is inceased, the igidity is impoved. Howeve, as the load is applied to the beaing, the life may become shotend abnomal heat may be geneated, esulting in seious failue, including ealy damage, seizue, etc. Also, in case of position peloading, the amount of peload vaies depending on the mounting conditions, including fitting of the beaing, the centifugal foce geneated duing the opeation and the tempeatue ise Vaiation of position peloading due to fitting and otation 1) Peload in mounting the beaing The angula contact ball beaing is shown as a model in Fig. 6. 4a. In case of the beaing fo the main shaft of a machine tool, fo which the inne ing is usually otated, the intefeence fit is employed fo the inne ing, and the cleaance fit is employed fo the oute ing. Howeve, the diamete of the inne ing aceway will expand due to intefeence, and the axial cleaance changes as shown in Fig. 6. 4b, esulting in the incease in the amount of peload. Futhemoe, if the inne ing is tightened by the shaft nut, etc., the width of the inne ing and the space will shink, esulting in incease in peload. This is the peload geneated when the beaing is mounted. A s0 T shaft Fig. 6. 4a Beaing befoe mounting δ Ast T δ IRt Fig. 6. 4b Change of dimension due to inne ing intefeence δ Asc δ Ast Fig. 6. 4c Change of dimension due to centifugal expansion of inne ing aceway δ Bte δ IRc δ ORte δ IRte 2) Change of peload duing otation Duing otation, the peload is changed by centifugal foce and tempeatue ise. When otating, the inne ing is affected by the centifugal foce and the aceway expands. Due to this expansion, the peload inceases as shown in Fig. 6. 4c. Influence of tempeatue ise is descibed below. When otating, the tempeatue of the beaing inceases and the components expand because of otation esistance, stiing esistance geneated by the lubicant, and othe extenal factos. The tempeatue incease of the inne ing and the olling elements is lage than that of the oute ing, which adiates heat easily. Theefoe, the intenal cleaance changes because of the expansion as shown in Fig. 6. 4d, and the peload is inceased. Also, the tempeatue diffeence is geneated between the oute ing and the housing, and the oute ing becomes hotte than the housing, educing the cleaance of the fitting suface of the oute ing. If the cleaance of the fitting suface of the oute ing is too small, the fitting of the oute ing becomes intefeence fitting because of the tempeatue diffeence, and the intenal cleaance changes due to the shinkage of the aceway of the oute ing, inceasing the peload as shown in Fig. 6. 4e. As a esult, it is also impotant to take into consideation the case whee the housing cools off excessively. δ Aste Fig. 6. 4d Change of dimension due to heat expansion δ Aso Cooling δ As Housing Fig. 6. 4e Change of dimension due to shinkage of oute ing aceway A s0 : initial stand-out value (The sum of the stand-out value of a pai of beaings is the size of the cleaance fo which the peload is povided.) T : intefeence of inne ing δ IRt : expansion of inne ing aceway due to inne ing intefeence δ Ast : change of beaing stand-out value due to inne ing intefeence δ IRc : centifugal expansion of inne ing aceway δ Asc : change of beaing stand-out value due to centifugal expansion of inne ing aceway δ IRte : heat expansion of inne ing aceway δ ORte : heat expansion of oute ing aceway δ Bte : heat expansion of olling element δ Aste : change of beaing stand-out value due to tempeatue ise of each component δ Aso : change of beaing stand-out value due to shinkage of oute ing aceway δ As : total of change of stand-out value due to mounting conditions and otation 27

29 I. Pecision Ball & Rolle Beaings Selecting peload and fitting To maintain the initial pefomance of the beaing and use it in stable condition, it is necessay to select an ideal peloading method and peload amount consideing the use conditions as well as the mounting conditions. Especially, when using the beaing at high speed, it is indispensable to select an ideal peload, taking into consideation the peload change, the pessue between the aceway and the olling elements geneated by centifugal foce, and the factos which cause spin slide of the angula contact ball beaing. The standad peload amount of each beaing is shown in the table of beaing dimensions. Also, the intefeences of the beaings fo main shafts in standad use condition ae shown in Figs and 6. 3 (page 26). Consult JTEKT fo detailed infomation about peloads and fittings when using the beaings at high speed with value d mn set at o moe o with a heavy load of C /P <13. Table 6. 2 Shaft fits (in the case of a otating inne ing) Beaing type Angula contact ball beaings Amount of peload peset fo matched pai beaings Geneal Cylindical olle beaings (cylindical boed in inne ing) Double-diection angula contact thust ball beaings Shaft diamete ove up to All shaft diamete Toleance class of shaft o dimensional toleance of shaft diamete (μm) Toleance class of beaing and fits Class 5 Classes 4, 2 Toleance class of shaft Taget intefeence o dimensional toleance (μm) of shaft diamete (μm) Taget intefeence (μm) js 5 js ~ ~2 0~2.5 0~3.5 0~4 0~4.5 0~ ~ ~ js 4 js k 4 k m 5 m n 5 n ~2 0~2 0~2.5 0~3.5 0~4 0~4.5 0~5 High-speed matched pai angula contact ball beaings All shaft diamete h 5 h 4 Suppot beaings fo pecision ball scews Tapeed olle js 5 beaings k 5 (metic seies) m 5 [ Remak ] Consult JTEKT fo specific opeating conditions (high-speed otation, otating oute ing, heavy load, etc.). 28

30 Table 6. 3 Housing fits (in the case of a otating inne ing) Beaing type Angula contact ball beaings Amount of peload peset fo matched pai beaings Geneal Housing boe diamete ove up to All housing boe diamete Housing boe diamete ove up to Toleance class of housing boe Beaing on fixed side Beaing on fee side Toleance class of beaing and fits Toleance class of beaing and fits Class 5 Classes 4, 2 Class 5 Classes 4, 2 Taget cleaance (μm) Toleance class of housing boe Toleance class of housing boe Toleance class of housing boe JS 5 JS 4 H 5 H 4 (Beaing on fixed side) (Toleance class of beaing and fits) Dimensional toleance of housing boe (μm) ±4.5 0~ ±5.5 0~ ±6.5 0~ ±7.5 0~5 Taget cleaance (μm) Classes 5, 4, 2 Classes 5, 4, 2 Taget cleaance (μm) ~11 8~13 10~ ±9 0~6 13~ ±10 0~7 17~ ±11.5 0~7 22~ ±12.5 0~8 + 9 Taget cleaance (μm) (Beaing on fee side) (Toleance class of beaing and fits) Dimensional toleance of housing boe (μm) ~10 Taget cleaance (μm) Taget cleaance (μm) 26~33 (Beaing type) Cylindical olle beaings Double-diection angula contact thust ball beaings High-speed matched paingula contact ball beaings Suppot beaings fo pecision ball scews Housing boe diamete ove up to All housing boe diamete Toleance class of housing boe K 5 0 K 4 0 K 5 K 4 H 6 Class 5 Taget cleaance (μm) Toleance class of housing boe Classes 4, 2 Class 5 Classes 4, 2 Taget cleaance (μm) Toleance class of housing boe Taget cleaance (μm) Toleance class of housing boe Tapeed olle beaings (metic seies) K 5 H 5 [ Remak ] Consult JTEKT fo specific opeating conditions (high-speed otation, oute ing otation, heavy load, etc.). H 6 Taget cleaance (μm) 29

31 I. Pecision Ball & Rolle Beaings 7. Limiting speeds of beaings The otational speed of a beaing is esticted chiefly by tempeatue inceases caused by fictional heat geneated within the beaing. When a speed limit is eached, it becomes impossible to continue opeation due to seizue and the like. The pemissible otational speed of a beaing epesents the value of limiting speed at which the beaing can continue opeation without cousing seizue-geneated tempeatues. Accodingly, the limiting speed diffes with beaing types, dimensions, accuacy, lubication methods, quality and quantity of lubicant, shape and mateial of cages, loading conditions (including amount of peload), etc. The limiting speed fo gease lubication o oil (oil / ai) lubication of beaings ae given in thei dimension tables. These values ae the limiting speed that ae applicable whee a beaing of a standad design is opeated unde nomal loading conditions (C /P 13, F a/f appox. 0.2). C : basic dynamic load ating P : dynamic equivalent load F : adial load F a : axial load Spindle beaings fo machine tools ae used in one of 2-, 3-, o 4-ow combinations. The limiting speed of a stack mounting beaing is lowe than that of a single ow beaing. The speed coefficients ae shown in Table In this table, the coelations between the peload amounts and the matching methods of the beaings mounted to the shafts with position peloading ae shown. Diffeences ae made due to the heat adiation and the vaiation in the peload amount of each beaing. Whee a lubicant can efficiently emove the heat geneated in the beaing, the limiting speed of a beaing will be geate than those given in the beaing dimension tables. If the otational speed of a beaing exceeds 80% of the value listed in the beaing dimension tables, caeful consideation should be given to the amount of peload, lubication method, lubicant, distance between the beaings, etc. Consult JTEKT. Matching method Pefix Table 7. 1 Speed coefficients Peload in mounting Peload S Peload L Peload M Peload H DB DBB DBD * The speed coefficients vay depending on the distance between the beaings. 30

32 8. Lubication Lubication is a citical issue fo beaings, on which thei pefomance geatly depends. The suitability of a lubicant and lubication method has geat influence on the pefomance of a beaing. Lubication plays the following oles. Lubication of each pat of the beaing educes wea and fiction. Removes heat in the beaing geneated by fiction and othe causes. Extends the sevice life of beaings by constantly foming an adequate oil film on the olling contact sufaces. Rust pevention and dust poofing fo beaings Lubication is vey impotant fo spindle beaings of machine tools since such beaings equie a low tempeatue incease unde high-speed opeation. Relationships between the quantity of lubicant and powe loss and between the quantity of lubicant and the tempeatue incease of the beaing ae shown in Fig Relationships between the viscosity of lubicant and powe loss and between the viscosity of lubicant and the tempeatue incease of the beaing ae shown in Fig (High) Tempeatue incease Powe loss Tempeatue incease A Powe loss B Oil quantity (lage) Fig Relationships between lubicant quantity and powe loss and between lubicant quantity and the tempeatue incease of the beaing The quantity of lubicant needed to meet the low tempeatue incease equiement lies in zone A whee the quantity of oil is small so the agitation loss is low, and zone B in which a lage quantity of oil tansfes heat fom the beaing to the outside. Regading the viscosity of lubicant, those which ae of elatively low viscosity ae suitable fo meeting the above-mentioned equiement. Note, howeve, that an excessively small quantity of oil o excessively low viscosity will not maintain a suitable lubicant film duing opeation, and futhe induce the chances of seizue. Fo beaing lubication methods, gease, oil / ai, o oil mist lubication is ecommended in zone A in Fig. 8. 1, and jet lubication, in zone B. Table 8. 1 shows a compaison of featues fo vaious lubication methods. It is impotant to select a lubication method and a lubicant to best suit to the machine specifications. Table 8. 1 Lubication method Gease Oil / ai Oil mist Jet Item lubication lubication lubication lubication Total cost K % % Tempeatue incease of beaing % K % K High-speed eliability K % K Powe loss K K K Volume occupied by lubicato Envionmental contamination Sevice life of lubicant Compaison of featues of diffeent lubication methods # : advantageous % : somewhat disadvantageous : disadvantageous K % % K % % K K K (High) Tempeatue incease Powe loss Tempeatue incease, Powe loss Viscosity (high) Fig Relationships between viscosity of lubicant and powe loss and between viscosity of lubicant and the tempeatue incease of the beaing 31

33 I. Pecision Ball & Rolle Beaings 8. 1 Gease lubication Gease lubication is most usually employed because it equies no special lubicatond the use of a elatively simple housing stuctue is sufficient. Howeve, to meet machine tool beaing equiements (high-speed opeation, low tempeatue incease, and long sevice life of sealed gease), the following should be taken into consideation Types of gease In ode to meet the low level tempeatue incease equiement of a beaings duing opeation, a gease low in base oil viscosity is suitable. In geneal, gease NLGI 2 in consistency and appoximately mm 2 /s in base oil viscosity is often used fo spindle beaings of machine tools. In cases whee beaings ae subjected to high loads, a gease with a base oil viscosity of appoximately 100 mm 2 /s, and an exteme-pessue agent may be used to secue lubicant film duing opeation. Table 8. 2 shows gease fo spindle beaings of machine tools. Fig Example of sealing device fo gease lubication (labyinth seal) Sealing device Fo spindle beaings of machine tools, it is impotant to use a eliable sealing device to pevent mixing of coolant, chips, wea paticle of dive belt, gea lubicant, and so foth. Whee gease lubication is adopted, contaminants have a geat influence on the sevice life of a beaing. An example of sealing device fo gease lubication is shown in Fig Table 8. 2 Gease fo spindle beaings of machine tools (epesentative examples) Gease name Manufactue Thickene Base oil Base oil viscosity mm 2 /s (40:) Application Beacon 325 Maltemp PS 2 Isoflex NBU 15 Exxon Mobil Kyodo oil NOK klübe Lithium Lithium Baium complex Dieste Dieste+mineal oil Dieste+mineal oil High-speed opeation, low tempeatue Stabags NBU 8 EP Alvania No. 2 NOK klübe Showa shell sekiyu Baium complex Lithium Mineal oil Mineal oil High-load opeation, wea esistance 32

34 8. 2 Oil lubication Oil / ai lubication In this lubication method, a small amount of oil of a specified quantity is supplied intemittently to each beaing by compessed ai. A schematic dawing of an oil / ai lubication system is shown in Fig Ai souce Ai cleaning unit Oil Oil / ai lubicato main unit Oil / ai lubicato mixing valve Ai Oil / ai Removes wate, oil, and contaminants. Opeates a pump intemittently to supply a deteminate quantity of oil mixed with ai. 3. Compaed with jet lubication, oil / ai lubication suppesses powe losses of beaings (see Fig. 8. 6). This featue saves space because a smalle dive motond cooling unit can be used. The stuctue of the main shaft can also be simple and compact. Tempeatue incease of oute ing ; Beaing dimensions : u70 u mm Position peloading Gease lubication Isoflex NBU15 sealed within 10% of inne space 5 10 Rotational speed Oil / ai lubication Oil equivalent to ISO VG ml/3min min 1 Fig Compaison of the tempeatue incease between oil / ai lubication and gease lubication kw 10 Beaing dimensions : u100 u mm Constant-pessue peloading Fig Oil / ai lubication system Since oil / ai lubication has featues as shown below, it has become popula in many high-speed spindle. 1. Compaed with gease lubication, oil / ai lubication allows beaings to meet the low tempeatue incease and high-speed opeation equiements (see Fig. 8. 5). This lubication method eliminates concens about the sevice life of lubicant as new oil is constantly supplied to the beaings. Futhemoe, compessed ai, which inceases the pessue in the housing, is effective in peventing contaminants. 2. Compaed with oil mist lubication, oil / ai lubication is simple to adjust the quantity of oil with a high degee of accuacy. This leads to a high eliability fo beaings duing high-speed opeation. In addition, unlike oil mist lubication, oil / ai lubication is fee fom envionmental contamination and also educes oil consumption. Powe loss Jet lubication Oil equivalent to ISO VG2 2.3L/min Oil / ai lubication Oil equivalent to ISO VG ml/3min Rotational speed 10 3 min 1 Fig Compaison of powe loss between oil / ai lubication and jet lubication In ode to take advantage of oil / ai lubication featues, JTEKT has poduced oil / ai lubicatos and ai cleaning units, of which we have special knowhow and have shipped to many customes. Consult JTEKT fo the appliation of the oil / ai lubication systems. Fo details of the oil / ai lubicatond ai cleaning unit, see "II. Oil / Ai Lubication System." Refe to Table 9. 4 on page 37 fo infomation about the dimensions of the spaces fo oil / ai lubication. Refe to Supplementay table 6 on page 219 fo infomation about the blow intevals of the oil / ai. 33

35 I. Pecision Ball & Rolle Beaings Oil mist lubication Simila to oil / ai lubication, oil mist lubication supplies a small quantity of oil to each beaing by compessed ai. Fig shows an oil mist lubication system. Ai souce Jet lubication Jet lubication is a method in which a lage quantity of lubicant is injected at a high velocities though the beaing side to lubicate and cool the beaing simultaneously. Fig shows a jet lubication system. Ai cleaning unit Oil mist geneato Removes wate, oil, contaminants, and contols ai pessue. Geneates oil mist (dy mist). Heat exchange, oil tank Filte Oil pump Nozzle convets dy mist into wet mist. Scavenge pump Flow contol valve Fig Oil mist lubication system The cost of oil mist lubication is elatively low. The high-speed pefomance attained by this method is bette than by gease lubication. To obtain maximum pefomance fom this method, due consideation should be given to the following. 1. Oil quantity settings The quantity of oil is set by the ate at which the oil mist geneato poduces oil dops. Since the ate of oil tuned to mist depends on the type of oil, ai pessue, flow ate, etc., it is impotant to detemine the amount of oil dops equied afte the chaacteistics of the whole system have been sufficiently undestood. 2. Distibution of mist to seveal beaings In geneal, a single oil mist geneato is used to distibute the mist to seveal beaings. Each beaing should be checked to see if it is supplied with an adequate quantity of oil. 3. Installation of suitable nozzle(s) The nozzle convets dy mist into wet mist suitable fo lubication of beaings and supplies mist to the inside of beaings. Fo eliable opeation, the nozzle design should be given sufficient consideation. A well-designed nozzle educes the quantity of oil so that contamination by oil mist will also be educed. Fig Jet lubication system Owing to its high eliability fo high-speed opeation, the jet lubication is often applied to such beaings designed fo high-speed and high-tempeatue opeation, fo example, gas tubine engines. Also, jet lubication is sometimes employed fo the high-speed spindles of machine tools. If this is the case, give due consideation to the following points. 1. Use oil of extemely low viscosity of appoximately 2 mm 2 /s to estain powe loss and tempeatue incease. 2. To impove cooling efficiency, set the velocity of the lubicant ejected fom the nozzle to at least 20% of the peipheal speed of the oute suface of the inne ing, theeby allowing moe oil to pass though the beaing. Installing seveal nozzles on the cicumfeence fo a lage quantity of oil is also effective to some degee. 3. A pump o simila device should be used to dischage oil smoothly. Fo this eason, the dischage pot should be as lage as possible to ensue a smooth dischage of oil. Afte dischage, the lubicant should be cooled with a heat exchange of adequate capacity in ode to minimize tempeatue changes. It is also essential to maintain clean lubicant by installing an appopiate filte, ensuing an aitight oil tank, and so foth. 34

36 9. Designing peipheal pats of beaings 9. 1 Toleances of shafts and housings When the innend oute ings of a beaing ae mounted on a shaft and a housing with a cetain intefeence, the shapes of the shaft and housing tend to influence the aceway suface of the beaing leading to a change in unning accuacy. Theefoe, shafts and housings need to be finished Table 9. 1 Toleances and suface oughness of shafts A ud A R a t t1 to maximum possible pecision. Recommended values fo toleances and suface oughness of shafts and housings ae shown in Tables 9. 1 and Refe to "III. Handling of Beaings" fo details about handling and mounting of the beaings. R a B udb ut4/300 B t3 AB Unit : μm Roundness(K) Cylindicity( ) Inclination( ) Deflection( ) Coaxiality( K) Roughness Shaft diamete t t 1 t 2 t 3 t 4 R a Toleance class of beaing Toleance class of beaing Toleance class of beaing Toleance class of beaing Toleance class of beaing Toleance class of beaing ove up to Class 5 Classes 4, 2 Class 5 Classes 4, 2 Classes 4, 2 Class 5 Classes 4, 2 Class 5 Classes 4, 2 Class 5 Classes 4, [ Remaks ] 1. Toleances, symbols, and efeence planes fo shafts comply with ISO/R When detemining the toleance in elation to the pemissible accuacy of shapes, the shaft diametes d A and d B ae used as efeence dimensions. t2 B t ut4 A Table 9. 2 Toleances and suface oughness of housings A t3 AB B t t1 ud A Ra Ra ud B t t1 ut4/300 B ut4/300 A Unit : μm Roundness(K) Cylindicity( ) Deflection( ) Coaxiality( K) Roughness Housing boe diamete t t 1 t 3 t 4 R a Toleance class of beaing Toleance class of beaing Toleance class of beaing Toleance class of beaing Toleance class of beaing ove up to Class 5 Classes 4, 2 Class 5 Classes 4, 2 Class 5 Classes 4, 2 Class 5 Classes 4, 2 Class 5 Classes 4, [ Remaks ] 1. Toleances, symbols, and efeence planes fo housings comply with ISO/R When detemining the toleance in elation to the pemissible accuacy of shapes, the housing boe diametes D A and D B ae used as efeence dimensions. 35

37 I. Pecision Ball & Rolle Beaings 9. 2 Limits of chamfe dimensions and fillet adii of shafts and housings 36 Table 9. 3 (1) Radial beaings (not applicable to tapeed olle beaings) Unit : mm (min.) o 1(min.) Nominal boe diamete d ove up to Radial diection [ Remak ] An imaginay ac with a adius of (min) is defined as being tangent to both the side face of the inne ing and the boe suface of the beaing; o to both the side face of oute ing and the outside suface of the beaing. Although an exact shape is not specified fo chamfeed sufaces, the outline in the axial plane shall not extend beyond the imaginay ac. Limits of chamfe dimensions and fillet adii of shafts and housings (max.) o 1(max.) Axial 1) diection (Refe.) Fillet adius of shaft o housing max (max.) o 1(max.) (Radial diection) (min.) o 1(min.) Side face of inne o oute ing (max.) o 1 (max.) (min.) o 1 (min.) (Axial diection) Boe o outside suface of beaing (min.) o 1 (min.) [ Note ] 1) Fo beaings 2mm o less in nominal width, the value of (max.) in the axial diection shall be the same as that in the adial diection. : dimension fo chamfeing innend oute ings 1 : dimension fo chamfeing the font and the likes of the innend oute ings (2) Metic tapeed olle beaings (min.) o 1(min.) 2) Nominal boe 1) o nominal outside diamete d o D ove up to Radial diection (max.) o 1(max.) Axial diection Unit : mm (Refe.) Fillet adius of shaft o housing max [ Notes ] 1) Inne ings ae classified by d, oute ings, by D. 2) Values in italics comply with JTEKT standads

38 9. 3 Spaces fo oil / ai lubication The dimensions of the spaces fo oil / ai lubication ae shown in Table Table 9. 4(1) Dimensions of the spaces fo oil / ai lubication Angula contact ball beaings 7000 seies 7200 seies 7900 seies Nozzle diamete 7000, 7200 seies 7900 seies uf ue P.C.D. A (nozzle) ud P.C.D. B (nozzle) uc Boe dia. No. Nozzle diamete (u) Boe dia. No. Nozzle diamete (u) Boe dia. No. Unit : mm Nominal 7000 seies 7200 seies 7900 seies boe dia. A B C D E F A B C D E F A B C D E F * Commonly used in contact angles of 15 and

39 I. Pecision Ball & Rolle Beaings Table 9. 4(2) Dimensions of the spaces fo oil / ai lubication Angula contact ball beaings HAR000 seies HAR900 seies 3NCHAR000 seies 3NCHAR900 seies uf ue P.C.D. A (nozzle) ud P.C.D. B (nozzle) uc Nozzle diamete HAR000, 3NCHAR000 seies HAR900, 3NCHAR900 seies Boe dia. No. Nozzle diamete (u) Boe dia. No. Nozzle diamete (u) Boe dia. No. Unit : mm Nominal HAR000, 3NCHAR000 seies HAR900, 3NCHAR900 seies boe dia. A B C D E F A B C D E F * Commonly used in contact angles of 15, 20 and

40 Table 9. 4(3) Dimensions of the spaces fo oil / ai lubication Angula contact ball beaings 3NCHAC000 seies 3NCHAC900 seies uf ue P.C.D. A (nozzle) ud P.C.D. B (nozzle) uc Nozzle diamete 3NCHAC000 seies Boe dia. No. Nozzle diamete (u) 3NCHAC900 seies Boe dia. No. Nozzle diamete (u) Nominal 3NCHAC000 seies 3NCHAC900 seies boe dia. A B C D E F A B C D E F Boe dia. No. Unit : mm * Commonly used in contact angles of 15 and

41 I. Pecision Ball & Rolle Beaings Table 9. 4(4) Dimensions of the spaces fo oil / ai lubication Angula contact ball beaings 3NCHAD000 seies Unit : mm Nominal 3NCHAD000 seies boe dia. A B C D E Boe dia. No ue ud Nozzle diamete 15 3NCHAD000 seies Boe dia. No. P.C.D. A (nozzle) uc ub Nozzle diamete (u) Table 9. 4(5) Dimensions of the spaces fo oil / ai lubication Angula contact ball beaings 3NCHAF000 seies 3NCHAF900 seies Unit : mm Nominal 3NCHAF000 seies 3NCHAF900 seies boe dia. A B C D E F A B C D E F Boe dia. No uf ue 15 Nozzle diamete 3NCHAF000 seies Boe dia. No. Nozzle diamete (u) 1 15 P.C.D. A (nozzle) ud P.C.D. B (nozzle) 3NCHAF900 seies Boe dia. No. uc Nozzle diamete (u)

42 Table 9. 4(6) Dimensions of the spaces fo oil / ai lubication Cylindical Rolle beaings NN3000 seies N1000 seies 3NCN1000 seies uf ue P.C.D. A (nozzle) ud P.C.D. B (nozzle) uc Nozzle diamete NN3000 seies Boe dia. No. Nozzle diamete (u) N1000, 3NCN1000 seies Boe dia. No. Nozzle diamete (u) Boe dia. No. Unit : mm Nominal NN3000 seies N1000, 3NCN1000 seies boe dia. A B C D E F A B C D E F

43 I. Pecision Ball & Rolle Beaings 10. High Ability angula contact ball beaings High Ability angula contact ball beaings ae optimized fo use on machine-tool spindles. They excel in high-speed pefomance and apid acceleation/deceleation, and ae especially supeio in ultahigh-speed applications when used with oil / ai lubication. Even with gease lubication, these beaings ae supeio to conventional poducts in highspeed applications Types and applications Featues High Ability angula contact beaings ae available in the vaieties listed in Table 10. 1, all of which diffe in stuctue and olling-element mateial. Select the type that is best suited fo the application. Table High Ability beaing types and pincipal applications Pincipal applications High-speed, high-igidity type High-speed, high load-ating type Ultafast, low-noise type fo oil / ai lubication Extemely ultafast type fo oil / ai lubication Taype Type R Type C Type D Type F Beaing dimension seies Specification Contact angle Mateial of olling element Steel o ceamics ceamics ceamics ceamics 20 to 30% eduction in tempeatue incease (compaed with JTEKT's conventional poducts) JTEKT has conducted vaious tests and analyses and developed elaboate machining techniques to impove the pefomance of beaings used with machining tool spindles. The esult is a substantial eduction in fictional heat geneated in beaings otating at a high speed to 1.5-time inceases in speed limits (compaed with JTEKT's conventional poducts) Speed limits have been extended though edesigning fo high-speed otation and heat eduction. Use of ceamic balls as olling elements enables additional high-speed otation. Impoved high-speed pefomance achieved by position peloading Low inceases in tempeatue duing opeation ensue educed changes in peload. Peload can be given by position peloading even at high speeds, which has been hitheto unavailable with conventional systems. The esult is high-pecision machining with stability. Conventional beaings easily eplaced Dimensions of High Ability beaings confom to ISO standads. Replacement of conventional beaings with High Ability beaings equies minimal geomety changes of the pesent spindle o housing. Oiling Oiling Oiling Oute ing space Oiling pot Oute ing Balls Cage Oute ing space Oiling pot Oute ing Balls Cage Inne ing space Oiling goove The oiling nozzle should be aligned with the oiling goove in the inne ing. Inne ing Fig Lubication method fo Type D High Ability Type D beaings ae designed fo oil / ai lubication. Thei inne ings have an oiling goove to ensue lubication on the olling contact suface fo impoved lubication eliability. Inne ing space Inne ing Lubication is accomplished fom one side via the oute ing. Fig Lubication method used in Type F The oiling pot in Type F is povided at its oute ing to ensue impoved lubication eliability on the guide ways of the cage. High Ability Type F beaings delive the best high-speed pefomance. 42

44 10. 3 Pefomance High Ability beaings exhibit thei maximum pefomance when used in pais o when moe than two units ae combined and when peload is given by position peloading. Shown below is the opeating pefomance of High Ability beaings with peload given by position peloading. 1) Pefomance of Types R and C Fig compaes elationships between otational speed and inceases in beaing tempeatue of Types R and C and conventional high-pecision beaings. High Ability beaings exhibit smalle tempeatue inceases and highe speed limits than conventional beaings whethe gease lubication o oil / ai lubication is applied. As shown in Fig , this type has excellent antiseizue chaacteistics with small quantity of lubicant oil in compaison with a conventional type. Thus, the quantity of the lubicant oil can be educed. Compaison of ceamic ball beaings [;] 40 Temp. incease of oute ing [;] 40 Temp. incease of oute ing Compaison of steel ball beaings [;] 60 Temp. incease of oute ing Beaing : u75 u115 20mm Lubication : Gease lubication 3NC HAC015C Peload : 980 N (position peloading) Cooling : jacket, oil-cooling Conventional type Rotational speed 1.75 dmn [ 10 6 ] [ 10 3 min 1 ] dmn [ 10 6 ] Beaing : u65 u100 18mm Lubication : Oil / ai lubication Peload : 150 N (position peloading) Cooling : jacket, oil-cooling Conventional type [ 10 3 min 1 ] Beaing : u65 u100 18mm Lubication : Oil / ai lubication Peload : 150 N (position peloading) Cooling : self-cooling Conventional type Rotational speed 3NC HAR013CA HAR013CA dmn [ 10 6 ] [ 10 3 min 1 ] Rotational speed Fig Compaison of inceases in beaing temp. [;] 60 Temp. incease of oute ing Compaison of ceamic ball beaings [;] 20 Temp. incease of oute ing Conventional oil / ai lub. Gease lub. 3NC HAR013CA Compaison of steel ball beaings [;] 20 Temp. incease of oute ing High Ability beaings also allow the possible change in lubication of the spindle fom oil / ai to gease. Fig shows an evaluation example Conventional oil / ai lub. Gease lub. HAR013CA dmn [ 10 6 ] [ 10 3 min 1 ] Rotational speed 10 5 Beaing : u70 u110 20mm Rotational speed : min 1 Cooling : self-cooling Lubicant viscosity : ISO VG32 Conventional type [ min ] Lubication inteval Beaing : u65 u100 18mm Peload : 150 N (position peloading) Cooling : jacket, oil-cooling Beaing : u65 u100 18mm Peload : 150 N (position peloading) Cooling : jacket, oil-cooling dmn [ 10 6 ] [ 10 3 min 1 ] Rotational speed 3NC HAR014CA Fig Compaison of seizue limit oil quantity of Type R and conventional type Fig Compaison of high-speed pefomance achieved by gease lubication Type R high ability ceamic ball beaing and gease lubication exhibits bette high-speed pefomance than conventional beaings using oil / ai lubication. If steel balls ae used, Type R with gease lubication exhibits high-speed pefomance equal to o bette than conventional beaings with oil / ai lubication. 43

45 I. Pecision Ball & Rolle Beaings 2) Pefomance of Type D Fig compaes the high-speed pefomance of Types D and R. [;] Temp. incease of oute ing Beaing : u35 u62 14mm Peload : 40 N (position peloading) Cooling : self-cooling Type R 3NC HAR007CA dmn [ 10 6 ] 2.5 Type D 3NC HAD007CA Rotational speed [ 10 3 min 1 ] Fig Compaison of inceases in the beaing temp. of Types R and D Also, Type D causes little wind oa when the beaing is otating, and is effective in educing the noise of the spindle device and the ai consumption. (Figs and 10. 8) 100 [dba] Sound pessue Beaing : u35 u62 14mm Peload : 40 N (position peloading) Cooling : self-cooling Type R 3NC HAR007CA Type D 3NC HAD007CA Rotational speed [ 10 3 min 1 ] Fig Compaison of noise by Types R and D 54 [;] 52 Temp. incease of dischage ai Beaing : u80 u125 22mm Rotational speed : min 1 Cooling : self-cooling Peload : 200 N (position peloading) Lubicant viscosity : ISO VG32 3NC HAD016CA Ai quantity Reduced by 20% Conventional type 3) Pefomance of Type F Fig shows an evaluation example of the Type F beaing opeated with a peload given by constant pessue peloading. The maximum otational speed achieved in this test, o min 1, equals in d mn value. Evaluation of beaing with a peload given by constant pessue peloading [;] 40 Temp. incease of oute ing Beaing : u50 u72 12mm Peload : 500 N (constant pessue peloading) Cooling : jacket, oil-cooling 3NC HAF910CA dmn [ 10 6 ] Rotational speed [ 10 3 min 1 ] Fig Temp. inceases in Type F beaing The oiling pot in the oute ing povides sufficient lubication to achieve a substantial eduction of fiction on cage iding land. This lubication method ensues excellent stability against apid acceleation o deceleation duing opeation. Passes 10 5 cycles of 0 to min -1 in 3s acceleation/deceleation ( min 1 =dmn ) Beaing numbe 3NC HAF910CA Peload constant pessue peloading Cooling jacket, oil-cooled Test patten See figue at ight. Rotational speed [ min 1 ] Fig Opeating patten of type F involving apid acceleation and deceleation Time [s] Supply ai quantity (pe beaing) [ Nl/min ] Fig Compaison of ai quantity of Type D and conventional type

46 11. Ceamic beaings fo machine tool spindles Compaed with beaing steel, ceamics [silicon nitide (Si 3N 4)] has supeio popeties such as light weight and high elasticity. One of the advantages of ceamics when used as a mateial fo beaings is a eduction in the slip of olling elements caused by centifugal foce and gyoscopic moments unde high-speed otation. Ceamic mateial is highly effective fo meeting the low tempeatue incease equiements of the beaing. Othedvantages include impoved igidity and impovements in seizue life and gease sevice life. Ceamic beaings, although vaying depending on opeating conditions, allow appoximately 30% to 50% impovement in speed as compaed with steel beaings Ceamic beaing stuctues and types Thee ae thee types of ceamic beaings diffeing in thei combinations of ceamic pats. Select the most suitable one fom Table accoding to the machine tool specifications. Table Ceamic beaing stuctues and types Code 1) Codes, types, and stuctues of ceamic beaings 3NC Desciption Rolling Inne ing element : ceamics Rolling : ceamics element Angula contact ball beaing Cylindical olle beaing 6NC NC Innend oute ings : ceamics Rolling element (Full-ceamic) Note 1) A code is placed befoe a basic beaing numbe Popeties of ceamics (Si 3 N 4 ) Sinteed in a high tempeatue and high-pessue gas atmospheic condition (HIP), ceamics (silicon nitide) has many supeio popeties such as heat esistance, light weight, low coefficient of linea expansion, and a high elastic modulus. Table shows a compaison of popeties with ceamics and beaing steel. Table Compaison of mechanical popeties Item Unit Heat esistance (in the ai) ; Density g/cm 3 Coefficient of linea expansion Vickes' hadness Young's modulus Poisson's atio Themal conductivity Coosion esistance Magnetism Electical conductivity Bonding fom of mateial K 1 HV GPa W/(m K) Ceamics (Si 3N 4 ) 11.3 Load atings of ceamic beaings Beaing steel (SUJ2) ~ ~ ~50.2 Good Non-magnetic mateial Not applicable (insulant) Covalent bond Not good Feomagnetic mateial Applicable (electic conducto) Metallic bond JTEKT has adopted the following values as a standad fo load atings of ceamic beaings. These values ae detemined fom a numbe of expeiments and thei esults. (1) Dynamic load ating : Dynamic load ating of steel beaings (C) 1.0 o geate (2) Static load ating : Static load ating of steel beaings (C 0) 1.0 The load applied to a spindle beaing fo machine tool is geneally vey small as compaed with beaing load atings. Accodingly, it is ae that a beaing eaches its fatigue sevice life o binelling occu in its aceway sufaces. Sufficient cae, howeve, should be taken to ensue that no impact load is applied to the beaing duing handling and opeation. 45

47 I. Pecision Ball & Rolle Beaings Sample test data of ceamic beaings 1) High-speed pefomance of beaings Ceamic is supeio to beaing steel in high-speed otation pefomance because it has lowe density and linea expansion coefficient. Compaison with steel beaing (1) Angula contact ball beaing 18 Peload : 150 N (position peloading) Oil / ai lubication Oil : (equivalent of ISO VG32) 0.03 ml / 8 min Ai : 46 L / min High-speed pefomance (1) Hybid ceamic Angula contact ball beaing 20 Peload : 490 N (position peloading) Gease : Isoflex NBU15 is sealed with a quantity of 10% of the inne space. u100 u65 u115 u75 [;] 80 dmn [ 10 6 ] [;] 80 dmn [ 10 6 ] Temp. incease of oute ing Steel beaing Hybid ceamic beaing Temp. incease of oute ing Not cooled Cooled Rotational speed [ 10 3 min 1 ] Rotational speed [ 10 3 min 1 ] Fig Compaison of Angula contact ball beaing Compaison with steel beaing (2) Fig High speed pefomance with gease lub. High-speed pefomance (2) Cylindical olle beaing Oil / ai lubication Oil : (equivalent of ISO VG10) 0.01 ml / 8 min Hybid ceamic Angula contact ball beaing 18 Peload : 150 N (position peloading) Oil / ai lubication Oil : (equivalent of ISO VG32) 0.03 ml / 8 min Ai : 46 L / min u140 u90 u100 u65 [;] dmn [ 10 6 ] 2.0 [;] 60 dmn [ 10 6 ] Temp. incease of oute ing Steel beaing Hybid ceamic beaing Temp. incease of oute ing Not cooled Cooled Rotational speed [ 10 3 min 1 ] Fig Compaison of cylindical olle beaing Rotational speed [ 10 3 min 1 ] Fig High speed pefomance with oil / ai lub.

48 The 6NC type hybid ceamic beaings, whose balls and inne ing ae both made of ceamic, ae supeio in high-speed pefomance to the 3NC type. In addition, the low-toque 6NC type beaings exhibit lowe powe losses at high otational speeds. High-speed pefomance (3) Hybid ceamic Angula contact ball beaing 2) Rigidity of beaing Since ceamics have a geate Young's modulus than beaing steel, the igidity of a ceamic beaing is highe than that of a steel beaing. Angula contact ball beaing 20 u u100 Oil / ai lubication Oil : (equivalent of ISO VG10) supplied at 0.05 ml / 2 min Ai : 60 L / min Cooling : Jacket, oil cooling (10 L / min, contol by oom tempeatue) u110 [μm] 60 u70 Temp. incease of dischage ai [;] Amount of peload 49 N 245 N 441 N 3NC type 6NC type Axial displacement Full-ceamic beaing : 0.77 Standad beaing (steel balls) : 1.0 Hybid ceamic beaing : Axial load [kn] Fig Compaison of axial displacement Rotational speed [ 10 3 min 1 ] 3) Changes in shaft dimensions Powe loss [kw] Amount of peload 49 N 245 N 441 N 3NC type 6NC type Compaed with steel beaings, ceamic beaings have highe igidity and lowe tempeatue incease, thus educing the isk of changes in shaft dimensions. Hybid ceamic angula contact ball beaing u u90 Oil / ai lubication Oil : (equivalent of ISO VG10) supplied at ml / min Ai : 50 L / min Gease lubication Isoflex NBU15 is sealed with a quantity of 10% of the inne space Rotational speed [ 10 3 min 1 ] Fig Compaison of 3NC type and 6NC type hybid ceamic beaings Since ceamics and steel have diffeent coefficients of linea expansion, Young's moduli, and Poisson's atios, cae should be taken when fitting fo mounting a 6NC type hybid ceamic beaing on a shaft is selected. Consult JTEKT. Displacement at shaft end [ m] Steel beaing (Gease) (Oil / ai) Ceamic beaing (Gease) (Oil / ai) Rotational Speed [ 10 3 min 1 ] Fig Compaison of displacement at shaft end 47

49 I. Pecision Ball & Rolle Beaings 4) Fatigue sevice life and seizue life of beaings Ceamic beaings ae supeio to steel beaings in both seizue life and fatigue sevice life. Seizue life test esults (1) Matched paingula contact ball beaing u140 Mateial of olling element Ceamics Beaing steel 48 u90 Rotational speed : min 1 Peload : 294 N Lubication : Afte unning fo 4h with oil / ai lubication povided, continue to un with lubication suspended. Oil : Equivalent of ISO VG ml / min Ai : 50 L / min Life, (h) Seizue life test esults (3) Cylindical olle beaing u47 Inne/oute ings Heatesistant steel 14 Rolle Ceamics Heat-esistant steel u20 Rotational speed : min 1 Lubication : Gease Tempeatue : 300 ; Relative seizue time atio Nomal Fig Seizue life test esults of hybid ceamic beaings and steel beaings Fig Seizue life test esults of hybid ceamic beaings and heat esisting steel beaings Seizue life test esults (2) Angula contact ball beaing Rotational speed : min 1 Axial load : 1.96 kn Lubication : Gease (Isoflex NBU15) is sealed with a quantity of 10% of the inne space. Fatigue sevice life test esult Angula contact ball beaing Rotational speed : min 1 Axial load : 14.7 kn Lubication : Oil bath u125 Inne/oute ings Beaing steel Ball Ceamics Beaing steel (standad beaing) u80 Seizue life, ( 10 3 h) Nomal Fig Seizue life test esults of hybid ceamic beaing and steel beaing u125 Viscosity of lubicant ISO VG68 ISO VG10 Mateial of olling element Ceamics Beaing steel Ceamics Beaing steel u80 Sevice life (Ratio of calculated sevice life) Inne ing : Inne ing : 13.8 Inne ing : 10.1 Teminated Inne ing : 16.3 Teminated Teminated Fig Life test esults of a hybid ceamic beaing 48

50 Pecision Ball & Rolle Beaings Beaing Dimension Tables

51

52 1. Angula Contact Ball Beaings Contents Page 1. 1 Types and featues of angula contact ball beaings Matched paingula contact ball beaings Composition of beaing numbes Toleance of beaings Standad peloads fo matched pai angula contact ball beaings Axial load and displacement 60 Beaing dimension tables 7900C seies C, 7000 seies C, 7200 seies CPA, 7000CPA, 7200CPA seies 76 HAR900C, HAR900CA, HAR900 seies 82 HAR000C, HAR000CA, HAR000 seies 88 3NCHAR900C, 3NCHAR900CA, 3NCHAR900 seies 94 3NCHAR000C, 3NCHAR000CA, 3NCHAR000 seies 100 3NCHAC900C, 3NCHAC900CA seies 106 3NCHAC000C, 3NCHAC000CA seies 110 3NCHAD000CA seies 114 3NCHAF900CA, 3NCHAF000CA seies

53

54 1. Angula contact ball beaings The angula contact ball beaing can eceive a adial load, unidiectional axial load, o combination of the above loads. Thee ae fou diffeent contact angles to choose fom when angula contact ball beaings ae consideed: 15 (contact angle symbol: C), 20 (CA), 30 (A: to be omitted), and 40 (B) (see Fig. 1. 1). Of these types, the 15 (contact angle symbol: C), 20 (CA) and 30 (A) beaings ae usually used fo spindle of machine tools. The geate the contact angle, the highe the axial igidity, and the smalle the contact angle, the moe advantageous fo high-speed otations. Contact angles Contact angle symbol C CA A (To be omitted) Fig Contact angles of angula contact ball beaings B 1. 1 Types and featues of angula contact ball beaings Standad angula contact ball beaings High Ability angula contact ball beaings 7900C 7000C C CPA 7000CPA 7200CPA HAR900C HAR900CA HAR900 HAR000C HAR000CA HAR000 HAC900C HAC900CA HAC000C HAC000CA HAD000CA HAF900CA HAF000CA *The beaing numbes of the HAC, HAD and HAF type poducts begin with the pefix "3NC," because they have ceamic balls as standad components. *Consult JTEKT, as the HAR000 seies can coespond to the non-contact seal. Fig Types and seies of angula contact ball beaings 1) Standad angula contact ball beaings 7900C 7000C, 7000 seies 7200C, 7200 The standad cage is of the ball-guided type and is made fom polyamide esin. 7900CPA, 7000CPA, 7200CPA seies The cages of these beaings ae of the oute ingguided type and ae made fom einfoced phenolic esin. This type of cage enables supeio high-speed pefomance. Beaings that can be disassembled into an oute ing, cage and ball assembly and inne ing ae also available. 2) High Ability angula contact ball beaings HAR900C, HAR900CA, HAR900 HAR000C, HAR000CA, HAR000 HAC000C, HAC000CA, HAC900C HAC900CA HAD000CA, HAF900CA, HAF000CA High igidity type High load-ating type Ulta-high speed type The High Ability angula contact ball beaings ae optimized fo use on high-speed machine tool spindles. They ae available in thee types: high igidity type, high load-ating type, and ultahighspeed type. (The ultahigh-speed type is used with oil / ai lubication.) The standad contact angle of these beaings is 20. The high igidity type poducts ae also available with a contact angle of 15 and 30. The high load-ating type poducts ae also available with a contact angle of 15. These beaings have ceamic balls and an oute ing-guided cage made fom einfoced phenol esin as standad components. Steel-ball poducts and ball-guided cage poducts ae also available to suit you needs. 53

55 1. Angula contact ball beaings 1. 2 Matched paingula contact ball beaings Angula contact ball beaings ae used in matched pai, o in combinations of moe than two beaings. Table 1. 1 shows combination types and symbols fo angula contact ball beaings. Table 1. 1 Combination types and symbols fongula contact ball beaings Type G beaings The type G beaing has both sides machined (flushgound) to obtain the same stand-out between the innend oute ings (see Fig. 1. 3). This makes it possible to select any desied combination(s) fom Table Combination types and symbols fongula contact ball beaings Matched pai Back-to-back Suffix : DB Face-to-face Suffix : DF Tandem Suffix : DT δ 2 δ 1 δ 1 =δ 2 Fig Flush-gound type G beaings Matched stack Suffix : DBD Suffix : DFD Suffix : DTD Suffix : DBB Suffix : DFF Examples of identification numbes of type G beaings 7010GL : Adjustment is made so that any combination of two o moe beaings pesents light peload (peload symbol : L). 7010GL 2 : Adjustment is made so that any combination of this set of two beaings pesents light peload (peload symbol : L). Suffix : DBT Suffix : DFT [Remak] indicates the diection of the "V" mak. Matched paingula contact ball beaings ae adjusted to a peset amount of peload and axial cleaance. The standad peloads ae divided into 4 classes : slight peload (symbol : S), light peload (L), medium peload (M), and heavy peload (H). Table 1. 4 (page 58) shows amounts of standad peloads. 54 Cautions fossembly q A "V" mak is put on the outside sufaces of the oute ings of matched pai o matched stack angula contact ball beaings, to indicate thei combination mode. Combine them in such a way that the maks on the oute ing fom a "V". (Combination mak) Mak indicating position of maximum eccenticity w Chamfeed edges of the innend oute ings ae maked with a cicle "K", which shows the position of maximum eccenticity. Mount beaings so that the "K" maks on the inne and oute ings ae opposite (180 ) to the position of maximum eccenticity of the shaft o housing. By doing so, maximum unning accuacy is obtained.

56 1. 3 Composition of beaing numbes (angula contact ball beaings) C P A K 5 D B L / 2 7 A F T P 5 3 N C H A R C - 5 K 5 D B C S 5 / 2 7 A F G P 4 Ceamic beaing Beaing type symbol 7 : angula contact ball beaing HAR HAC High Ability angula HAD contact ball beaings HAF Dimension seies symbol 9 : dimension seies 19 0 : dimension seies 10 2 : dimension seies 02 Boe diamete numbe 18 : nominal boe diamete : 90 mm (boe diamete numbe 5 equals nominal boe diamete.) Contact angle symbol A : nominal contact angle : 30 (A is to be omitted.) B : nominal contact angle : 40 C : nominal contact angle : 15 CA : nominal contact angle : 20 Cage guiding system symbol No specified : inne ing-guiding (oute ing-guiding fo HAR, HAC, HAD, HAF) PA : oute ing-guiding 5 : ball-guiding Special pemissible dimensional deviation symbol K5 : JTEKT's special pemissible dimensional deviations ae used fo the boe diamete of the inne ing and the outside diamete of the oute ing. No specified : If standad pemissible dimensional deviations ae used. Toleance class symbol P5 : JIS class 5 P4 : JIS class 4 P2 : JIS class 2 Cage symbol FG : molded cage made of polyamide esin FT : machined cage made of einfoced phenolic FY : machined cage made of coppelloy Space numbe/symbol No specified : If no space is povided. /27 : space with lubication hole, 27 mm in nominal width A : space not povided with lubication hole (symbol A is not used if the space has a lubication hole.) Peload symbol o cleaance symbols ( In some cases, a symbol denoting the specific peload is used.) S : slight peload CS : cleaance L : light peload CY : negative cleaance (peload) M : medium peload (CS5 : The mean value of the H : heavy peload cleaance is 5μm.) (Fomount of peload, see Table 1. 4 (page 58).) Matched pai o stack symbol DB : back-to-back DF : face-to-face DT : tandem Fo suffixes that denote beaings which consist of thee o fou beaings, see Table 1. 1 (page 54). G : Type G beaing (flush-gound beaing) 55

57 1. Angula contact ball beaings 1. 4 Toleance of beaings The toleance of the pecision angula contact ball beaing is compliant with pemissible dimensional deviations and limits of classes 5, 4, and 2 as specified in JIS B 1514 fo adial beaings (tapeed olle beaings not included). Pemissible dimensional deviations and limits of adial beaings ae shown in Table Table 1. 3 (page 57) shows JTEKT's special pemissible dimensional deviations (K5) used to facilitate multi-ow combinations (K5 is used fo the boe diamete of the inne ing and the outside diamete of the oute ing). Table 1. 2(1) Pemissible dimensional deviations and limits of angula contact ball and cylindical olle beaings (1) Inne ing Nominal boe diamete d Single plane mean boe Single boe Single plane boe diamete deviation diamete deviation diamete vaiation Diamete seies 3 dmp 3 ds 1) Diamete seies 7, 8, 9 0, 1, 2, 3, 4 Unit : μm Mean boe diamete vaiation Class 5 Class 4 Class 2 Class 4 Class 2 ove up to uppe lowe uppe lowe uppe lowe uppe lowe uppe lowe max. max. max. max Class 5 Class 4 Class 5 Class 4 V dsp Class 2 Class 5 V dmp Class 4 Class 2 Nominal boe diamete d 56 Radial unout of assembled beaing inne ing K ia S d Class 4 S ia 2) Single inne ing width deviation 3 Bs Single inne ing width deviation 3 Bs 3) Inne ing width vaiation V Bs Class Class Class Class Class Class Class Class Class Class 2 Classes 5, 4 Class Classes 5, ove up to max. max. max. uppe lowe uppe lowe uppe lowe max ) ) ) ) S d : Pependiculaity of inne ing face with espect to the boe S ia : Axial unout of assembled beaing inne ing [Notes] 1) Toleance class 4 is applied to beaings of diamete seies 0, 1, 2, 3, and 4. 2) Applied to angula contact ball beaings. 3) Applied to individual beaing ings manufactued fo matched pai o stack beaings. 4) Class 5 toleance complies with JIS; class 4 toleance is JTEKT standad. [Remak] Values in italics comply with JTEKT standads. ud B ud Class 2 d : nominal boe diamete D : nominal outside diamete B : nominal beaing width

58 Table 1. 2(2) Pemissible dimensional deviations and limits of angula contact ball and cylindical olle beaings (2) Oute ing Nominal outside diamete D Single plane mean outside Single outside Single plane outside diamete deviation diamete deviation diamete vaiation Diamete seies 3 Dmp 3 Ds 1) Diamete seies 7, 8, 9 0, 1, 2, 3, 4 Unit : μm Mean outside diamete vaiation Class 5 Class 4 Class 2 Class 4 Class 2 ove up to uppe lowe uppe lowe uppe lowe uppe lowe uppe lowe max. max. max. max Class 5 Class 4 Class 5 Class 4 V Dsp Class 2 Class 5 V Dmp Class 4 Class 2 Nominal outside diamete D Radial unout of assembled beaing oute ing K ea Pependiculaity of oute ing outside suface with espect to the face S D Class 4 Axial unout of assembled beaing oute ing 2) S ea Deviation of a single oute ing width 3 Cs Ring width vaiation V Cs Class 4 Class Class Class Class Class Class Class Class Classes Class Class , 4, ove up to max. max. max. uppe lowe max Same as toleance Bs, d being that of the same beaing [ Notes ] 1) Toleance class 4 is applied to beaings of diamete seies 0, 1, 2, 3, and 4. 2) Applied to angula contact ball beaings. [ Remak ] Values in italics comply with JTEKT standads. ud B ud d : nominal boe diamete D : nominal outside diamete B : nominal beaing width Table 1. 3 JTEKT's specific toleances of angula contact ball beaings (K5) 1) Single plane mean boe o Unit : μm Nominal boe diameted d outside diamete deviation Class 5 3 dmp, 3 Dmp Class 4 ove up to uppe lowe uppe lowe ud ud d : nominal boe diamete D : nominal outside diamete [Note] 1) K5 denotes specially fomulated JTEKT standads fo the pupose of minimizing individual diffeences in pefomance, which may occus a esult of fitting stack-mounted to beaings. 57

59 1. Angula contact ball beaings 1. 5 Standad peloads fo matched paingula contact ball beaings Back-to-back and face-to-face matched pai beaings ae often used unde peload. By applying a peload to a beaing, the following effects ae ealized. 1 ) The igidity of a beaing can be impoved. 2 ) Running accuacy is impoved. 3 ) Abnomal noise caused by vibation and esonance is pevented. A geate peload esults in highe beaing igidity. Howeve, such peload also influences othe paametes of the beaing : sevice life, tempeatue, fictional toque, etc. Theefoe, it is impotant to select an adequate peload, taking into consideation the otational speed and lubication conditions. JTEKT offes 4 types of peset peloads, slight peload (S), light peload (L), medium peload (M), and heavy peload (H). This will enable the use to select any desied peload suitable fo individual applications (see Table 1. 4). As a guide fo selecting the peload, light o medium peload is used fo spindles of ginding machines, while medium o heavy peloads ae used fo spindle of lathes and milling machines. Table 1. 4(1) Standad peloads fo matched paingula contact ball beaings (S : slight peload; L : light peload; M : medium peload; H : heavy peload) Unit : N Boe dia. Boe dia. 7900C, 7900CPA 7000C, 7000CPA 7000 No. S L M S L M H L M H

60 Table 1. 4(2) Standad peloads fo matched paingula contact ball beaings (S : slight peload; L : light peload; M : medium peload; H : heavy peload) Unit : N Boe dia. Boe dia. 7200C, 7200CPA 7200 No. S L M H L M H

61 1. Angula contact ball beaings 1. 6 Axial load and displacement (angula contact ball beaings) Fig shows elationships between axial load and displacement of KOYO angula contact ball beaings. The gaphs indicate that the geate the contact angle of a beaing, the smalle the axial displacement (1) 7900C, 7900CPA seies (contact angle : 15 ) (µm) Axial displacement (Boe diamete numbe) (high igidity). The displacement cuve of duplex beaings unde given peload is detemined by the method shown in Fig on page 26. (2) 7000C, 7000CPA seies (contact angle : 15 ) 60 (µm) Axial displacement (Boe diamete numbe) Axial load (kn) (3) 7000 seies (contact angle : 30 ) (µm) 30 Axial displacement (Boe diamete numbe) (4) 7200C, 7200CPA seies (contact angle : 15 ) (µm) Axial displacement Axial load (kn) (Boe diamete numbe) Axial load (kn) Axial load (kn) Fig (1) Relationships between axial load and displacement (angula contact ball beaings) *The axial displacements shown above ae values of the single-ow beaings not peloaded.

62 (5) 7200 seies (contact angle : 30 ) (6) HAR900C seies (contact angle : 15 ) (µm) Axial displacement (Boe diamete numbe) (µm) Axial displacement (Boe diamete numbe) Axial load (kn) Axial load (kn) (7) HAR900CA seies (contact angle : 20 ) 40 (µm) Axial displacement (Boe diamete numbe) (8) HAR900 seies (contact angle : 30 ) (µm) Axial displacement (Boe diamete numbe) Axial load (kn) Axial load (kn) Fig (2) Relationships between axial load and displacement (angula contact ball beaings) *The axial displacements shown above ae values of the single-ow beaings not peloaded. 61

63 1. Angula contact ball beaings (9) HAR000C seies (contact angle : 15 ) (10) HAR000CA seies (contact angle : 20 ) (µm) Axial displacement (Boe diamete numbe) (µm) Axial displacement (Boe diamete numbe) Axial load (kn) Axial load (kn) (11) HAR900 seies (contact angle : 30 ) (12) 3NCHAR900C seies (contact angle : 15 ) (µm) Axial displacement (Boe diamete numbe) (µm) Axial displacement (Boe diamete numbe) Axial load (kn) Axial load (kn) Fig (3) Relationships between axial load and displacement (angula contact ball beaings) *The axial displacements shown above ae values of the single-ow beaings not peloaded. 62

64 (13) 3NCHAR900CA seies (contact angle : 20 ) (µm) Axial displacement (Boe diamete numbe) (14) 3NCHAR900 seies (contact angle : 30 ) (µm) Axial displacement (Boe diamete numbe) Axial load (kn) Axial load (kn) (15) 3NCHAR000C seies (contact angle : 15 ) (µm) Axial displacement (Boe diamete numbe) (16) 3NCHAR000CA seies (contact angle : 20 ) (µm) Axial displacement (Boe diamete numbe) Axial load (kn) Axial load (kn) Fig (4) Relationships between axial load and displacement (angula contact ball beaings) *The axial displacements shown above ae values of the single-ow beaings not peloaded. 63

65 1. Angula contact ball beaings (17) 3NCHAR000 seies (contact angle : 30 ) (18) 3NCHAC900C seies (contact angle : 15 ) (μm) Axial displacement (Boe diamete numbe) (μm) Axial displacement (Boe diamete numbe) Axial load (kn) Axial load (kn) (19) 3NCHAC900CA seies (contact angle : 20 ) (20) 3NCHAC000C seies (contact angle : 15 ) (μm) Axial displacement (Boe diamete numbe) (μm) Axial displacement (Boe diamete numbe) Axial load (kn) Axial load (kn) Fig (5) Relationships between axial load and displacement (angula contact ball beaings) *The axial displacements shown above ae values of the single-ow beaings not peloaded. 64

66 (21) 3NCHAC000CA seies (contact angle : 20 ) (22) 3NCHAD000CA seies (contact angle : 20 ) (μm) Axial displacement (Boe diamete numbe) (μm) Axial displacement (Boe diamete numbe) Axial load (kn) Axial load (kn) (23) 3NCHAF900CA seies (contact angle : 20 ) (μm) Axial displacement (Boe diamete numbe) (24) 3NCHAF000CA seies (contact angle : 20 ) 40 (μm) Axial displacement (Boe diamete numbe) Axial load (kn) Axial load (kn) Fig (6) Relationships between axial load and displacement (angula contact ball beaings) *The axial displacements shown above ae values of the single-ow beaings not peloaded. 65

67 1. Angula contact ball beaings 7900C seies Contact angle 15 B 1 ud a 2 B 2 B 2 B ud ud a ud a a 1 a 2 Back-to-back (DB) Face-to-face (DF) Tandem (DT) ud b b ud a ud a ud a Static equivalent load P 0=X 0 F +Y 0 F a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0<F. Dynamic equivalent load P =XF +YF a Contact angle 1 if 0F a C0 e Single ow/tandem F a F e a > e F F a F e a > e F X Y X Y X Y X Y ) Fo i, use 2 fo DB & DF and 1 fo single & DT. F Back-to-back/Face-to-face F Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Facto f 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C [ Remaks ] 1. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(1) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings. 67

68 1. Angula contact ball beaings 7000C seies Contact angle 15 B 1 2 B 2 B 2 B a b Static equivalent load P 0=X 0 F +Y 0 F a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0<F. Dynamic equivalent load P =XF +YF a ud ud ud a ud a a 1 a 2 ud b ud a ud a ud a Contact angle 1 if 0F a C0 e Single ow/tandem F a F e a > e F F Back-to-back/Face-to-face F a F e a > e F X Y X Y X Y X Y F a Back-to-back (DB) Face-to-face (DF) Tandem (DT) ) Fo i, use 2 fo DB & DF and 1 fo single & DT. Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Facto f 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C [ Remaks ] 1. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(1) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings. 69

69 1. Angula contact ball beaings 7000 seies Contact angle 30 B 2 B 2 B 2 B 1 a b Static equivalent load P 0=X 0 F +Y 0 F a ud ud ud a ud a a 1 a 2 ud b ud a ud a ud a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0<F. Dynamic equivalent load P =XF +YF a a Back-to-back (DB) Face-to-face (DF) Tandem (DT) Contact angle Single ow/tandem F a Back-to-back/Face-to-face F F e e a > e e a > e F F F F X Y X Y X Y X Y F a Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No [ Remaks ] 1. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(1) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings. 71

70 1. Angula contact ball beaings 7200C seies Contact angle 15 B 1 2 B 2 B 2 B a b Static equivalent load P 0=X 0 F +Y 0 F a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0<F. Dynamic equivalent load P =XF +YF a ud ud ud a ud a a 1 a 2 ud b ud a ud a ud a Contact angle 1 if 0F a C0 e Single ow/tandem F a F e a > e F F Back-to-back/Face-to-face F a F e a > e F X Y X Y X Y X Y F a Back-to-back (DB) Face-to-face (DF) Tandem (DT) ) Fo i, use 2 fo DB & DF and 1 fo single & DT. Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Facto f 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C [ Remaks ] 1. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(1) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings. 73

71 1. Angula contact ball beaings 7200 seies Contact angle 30 B 2 B 2 B 2 B 1 a b Static equivalent load P 0=X 0 F +Y 0 F a ud ud ud a ud a a 1 a 2 ud b ud a ud a ud a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0<F. Dynamic equivalent load P =XF +YF a a Back-to-back (DB) Face-to-face (DF) Tandem (DT) Contact angle Single ow/tandem F a Back-to-back/Face-to-face F F e e a > e e a > e F F F F X Y X Y X Y X Y F a Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No [ Remaks ] 1. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(1) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings. 75

72 1. Angula contact ball beaings 7900CPA seies Contact angle 15 B 2 B 2 B 2 B Static equivalent load P 0=X 0 F +Y 0 F a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0<F. Dynamic equivalent load P =XF +YF a ud 1 a ud ud a ud a a 1 a 2 Back-to-back (DB) Face-to-face (DF) Tandem (DT) ud a ud a ud a b ud b Contact angle 1 if 0F a C0 e Single ow/tandem F a F e a > e F Back-to-back/Face-to-face F a F e a > e F X Y X Y X Y X Y ) Fo i, use 2 fo DB & DF and 1 fo single & DT. F F Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Facto f 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA [ Remaks ] 1. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(1) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings. 77

73 1. Angula contact ball beaings 7000CPA seies Contact angle 15 B 2 B 2 B 2 B Static equivalent load P 0=X 0 F +Y 0 F a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0<F. Dynamic equivalent load P =XF +YF a ud 1 a ud ud a ud a a 1 a 2 Back-to-back (DB) Face-to-face (DF) Tandem (DT) ud a ud a ud a b ud b Contact angle 1 if 0F a C0 e Single ow/tandem F a F e a > e F Back-to-back/Face-to-face F a F e a > e F X Y X Y X Y X Y ) Fo i, use 2 fo DB & DF and 1 fo single & DT. F F Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Facto f 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA [ Remaks ] 1. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(1) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings. 79

74 1. Angula contact ball beaings 7200CPA seies Contact angle 15 B 2 B 2 B 2 B Static equivalent load P 0=X 0 F +Y 0 F a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0<F. Dynamic equivalent load P =XF +YF a ud 1 ud ud a ud a a 1 a 2 ud a ud a ud a b ud b Contact angle 1 if 0F a C0 e Single ow/tandem F a F e a > e F F Back-to-back/Face-to-face F a F e a > e F X Y X Y X Y X Y F a Back-to-back (DB) Face-to-face (DF) Tandem (DT) ) Fo i, use 2 fo DB & DF and 1 fo single & DT. Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Facto f 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA CPA [ Remaks ] 1. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(1) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings. 81

75 1. Angula contact ball beaings HAR900C seies Contact angle 15 B 1 2 B 2 B 2 B b Static equivalent load P 0=X 0 F +Y 0 F a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0<F. Dynamic equivalent load P =XF +YF a ud ud ud a ud a a 1 a 2 ud b ud a ud a ud a Contact angle 1 if 0F a C0 e Single ow/tandem F a F e a > e F F Back-to-back/Face-to-face F a F e a > e F X Y X Y X Y X Y F a Back-to-back (DB) Face-to-face (DF) Tandem (DT) ) Fo i, use 2 fo DB & DF and 1 fo single & DT. Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Facto f 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No HAR908C HAR908C HAR909C HAR909C HAR910C HAR910C HAR911C HAR911C HAR912C HAR912C HAR913C HAR913C HAR914C HAR914C HAR915C HAR915C HAR916C HAR916C HAR917C HAR917C HAR918C HAR918C HAR919C HAR919C HAR920C HAR920C HAR921C HAR921C HAR922C HAR922C HAR924C HAR924C HAR926C HAR926C HAR928C HAR928C HAR930C HAR930C HAR932C HAR932C HAR934C HAR934C [ Remaks ] 1. Bounday dimensions of this beaing ae the same as those of the 7900 seies. 2. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(2) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page 219. Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings

76 1. Angula contact ball beaings HAR900CA seies Contact angle 20 B 2 B 2 B 2 B 1 b Static equivalent load P 0=X 0 F +Y 0 F a ud ud ud a ud a a 1 a 2 ud b ud a ud a ud a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0>F. Dynamic equivalent load P =XF +YF a a Back-to-back (DB) Face-to-face (DF) Tandem (DT) Contact angle Single ow/tandem F a Back-to-back/Face-to-face F F e e a > e e a > e F F F F X Y X Y X Y X Y F a Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No HAR908CA HAR908CA HAR909CA HAR909CA HAR910CA HAR910CA HAR911CA HAR911CA HAR912CA HAR912CA HAR913CA HAR913CA HAR914CA HAR914CA HAR915CA HAR915CA HAR916CA HAR916CA HAR917CA HAR917CA HAR918CA HAR918CA HAR919CA HAR919CA HAR920CA HAR920CA HAR921CA HAR921CA HAR922CA HAR922CA HAR924CA HAR924CA HAR926CA HAR926CA HAR928CA HAR928CA HAR930CA HAR930CA HAR932CA HAR932CA HAR934CA HAR934CA [ Remaks ] 1. Bounday dimensions of this beaing ae the same as those of the 7900 seies. 2. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(2) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page 219. Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings

77 1. Angula contact ball beaings HAR900 seies Contact angle 30 B 2 B 2 B 2 B 1 b Static equivalent load P 0=X 0 F +Y 0 F a ud ud ud a ud a a 1 a 2 ud b ud a ud a ud a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0<F. Dynamic equivalent load P =XF +YF a a Back-to-back (DB) Face-to-face (DF) Tandem (DT) Contact angle Single ow/tandem F a Back-to-back/Face-to-face F F e e a > e e a > e F F F F X Y X Y X Y X Y F a Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR934 [ Remaks ] 1. Bounday dimensions of this beaing ae the same as those of the 7900 seies. 2. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(2) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page 219. Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings

78 1. Angula contact ball beaings HAR000C seies Contact angle 15 B 1 2 B 2 B 2 B b Static equivalent load P 0=X 0 F +Y 0 F a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0<F. Dynamic equivalent load P =XF +YF a ud ud ud a ud a a 1 a 2 ud b ud a ud a ud a Contact angle 1 if 0F a C0 e Single ow/tandem F a F e a > e F F Back-to-back/Face-to-face F a F e a > e F X Y X Y X Y X Y F a Back-to-back (DB) Face-to-face (DF) Tandem (DT) ) Fo i, use 2 fo DB & DF and 1 fo single & DT. Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Facto f 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No HAR006C HAR006C HAR007C HAR007C HAR008C HAR008C HAR009C HAR009C HAR010C HAR010C HAR011C HAR011C HAR012C HAR012C HAR013C HAR013C HAR014C HAR014C HAR015C HAR015C HAR016C HAR016C HAR017C HAR017C HAR018C HAR018C HAR019C HAR019C HAR020C HAR020C HAR021C HAR021C HAR022C HAR022C HAR024C HAR024C HAR026C HAR026C HAR028C HAR028C HAR030C HAR030C HAR032C HAR032C HAR034C HAR034C [ Remaks ] 1. Bounday dimensions of this beaing ae the same as those of the 7000 seies. 2. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(2) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page 219. Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings

79 1. Angula contact ball beaings HAR000CA seies Contact angle 20 B 2 B 2 B 2 B 1 b Static equivalent load P 0=X 0 F +Y 0 F a ud ud ud a ud a a 1 a 2 ud b ud a ud a ud a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0>F. Dynamic equivalent load P =XF +YF a a Back-to-back (DB) Face-to-face (DF) Tandem (DT) Contact angle Single ow/tandem F a Back-to-back/Face-to-face F F e e a > e e a > e F F F F X Y X Y X Y X Y F a Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No HAR006CA HAR006CA HAR007CA HAR007CA HAR008CA HAR008CA HAR009CA HAR009CA HAR010CA HAR010CA HAR011CA HAR011CA HAR012CA HAR012CA HAR013CA HAR013CA HAR014CA HAR014CA HAR015CA HAR015CA HAR016CA HAR016CA HAR017CA HAR017CA HAR018CA HAR018CA HAR019CA HAR019CA HAR020CA HAR020CA HAR021CA HAR021CA HAR022CA HAR022CA HAR024CA HAR024CA HAR026CA HAR026CA HAR028CA HAR028CA HAR030CA HAR030CA HAR032CA HAR032CA HAR034CA HAR034CA [ Remaks ] 1. Bounday dimensions of this beaing ae the same as those of the 7000 seies. 2. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(2) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page 219. Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings

80 1. Angula contact ball beaings HAR000 seies Contact angle 30 B 2 B 2 B 2 B 1 b Static equivalent load P 0=X 0 F +Y 0 F a ud ud ud a ud a a 1 a 2 ud b ud a ud a ud a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0<F. Dynamic equivalent load P =XF +YF a a Back-to-back (DB) Face-to-face (DF) Tandem (DT) Contact angle Single ow/tandem F a Back-to-back/Face-to-face F F e e a > e e a > e F F F F X Y X Y X Y X Y F a Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR HAR034 [ Remaks ] 1. Bounday dimensions of this beaing ae the same as those of the 7000 seies. 2. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(2) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page 219. Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings

81 1. Angula contact ball beaings Ceamic beaings 3NCHAR900C seies Contact angle 15 B 1 2 B 2 B 2 B b Static equivalent load P 0=X 0 F +Y 0 F a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0<F. Dynamic equivalent load P =XF +YF a ud ud ud a ud a a 1 a 2 ud b ud a ud a ud a Contact angle 1 if 0F a C0 e Single ow/tandem F a F e a > e F F Back-to-back/Face-to-face F a F e a > e F X Y X Y X Y X Y F a Back-to-back (DB) Face-to-face (DF) Tandem (DT) ) Fo i, use 2 fo DB & DF and 1 fo single & DT. Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Facto f 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No NCHAR908C NCHAR908C NCHAR909C NCHAR909C NCHAR910C NCHAR910C NCHAR911C NCHAR911C NCHAR912C NCHAR912C NCHAR913C NCHAR913C NCHAR914C NCHAR914C NCHAR915C NCHAR915C NCHAR916C NCHAR916C NCHAR917C NCHAR917C NCHAR918C NCHAR918C NCHAR919C NCHAR919C NCHAR920C NCHAR920C NCHAR921C NCHAR921C NCHAR922C NCHAR922C NCHAR924C NCHAR924C NCHAR926C NCHAR926C NCHAR928C NCHAR928C NCHAR930C NCHAR930C NCHAR932C NCHAR932C NCHAR934C NCHAR934C [ Remaks ] 1. Bounday dimensions of this beaing ae the same as those of the 7900 seies. 2. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(2) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page 219. Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings

82 1. Angula contact ball beaings 3NCHAR900CA seies Contact angle 20 Ceamic beaings B 2 B 2 B 2 B 1 b Static equivalent load P 0=X 0 F +Y 0 F a ud ud ud a ud a a 1 a 2 ud b ud a ud a ud a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0>F. Dynamic equivalent load P =XF +YF a a Back-to-back (DB) Face-to-face (DF) Tandem (DT) Contact angle Single ow/tandem F a Back-to-back/Face-to-face F F e e a > e e a > e F F F F X Y X Y X Y X Y F a Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No NCHAR908CA NCHAR908CA NCHAR909CA NCHAR909CA NCHAR910CA NCHAR910CA NCHAR911CA NCHAR911CA NCHAR912CA NCHAR912CA NCHAR913CA NCHAR913CA NCHAR914CA NCHAR914CA NCHAR915CA NCHAR915CA NCHAR916CA NCHAR916CA NCHAR917CA NCHAR917CA NCHAR918CA NCHAR918CA NCHAR919CA NCHAR919CA NCHAR920CA NCHAR920CA NCHAR921CA NCHAR921CA NCHAR922CA NCHAR922CA NCHAR924CA NCHAR924CA NCHAR926CA NCHAR926CA NCHAR928CA NCHAR928CA NCHAR930CA NCHAR930CA NCHAR932CA NCHAR932CA NCHAR934CA NCHAR934CA [ Remaks ] 1. Bounday dimensions of this beaing ae the same as those of the 7900 seies. 2. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(2) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page 219. Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings

83 1. Angula contact ball beaings 3NCHAR900 seies Contact angle 30 Ceamic beaings B 2 B 2 B 2 B 1 b Static equivalent load P 0=X 0 F +Y 0 F a ud ud ud a ud a a 1 a 2 ud b ud a ud a ud a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0<F. Dynamic equivalent load P =XF +YF a a Back-to-back (DB) Face-to-face (DF) Tandem (DT) Contact angle Single ow/tandem F a Back-to-back/Face-to-face F F e e a > e e a > e F F F F X Y X Y X Y X Y F a Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR934 [ Remaks ] 1. Bounday dimensions of this beaing ae the same as those of the 7900 seies. 2. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(2) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page 219. Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings

84 1. Angula contact ball beaings Ceamic beaings 3NCHAR000C seies Contact angle 15 B 1 2 B 2 B 2 B b Static equivalent load P 0=X 0 F +Y 0 F a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0<F. Dynamic equivalent load P =XF +YF a ud ud ud a ud a a 1 a 2 ud b ud a ud a ud a Contact angle 1 if 0F a C0 e Single ow/tandem F a F e a > e F F Back-to-back/Face-to-face F a F e a > e F X Y X Y X Y X Y F a Back-to-back (DB) Face-to-face (DF) Tandem (DT) ) Fo i, use 2 fo DB & DF and 1 fo single & DT. Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Facto f 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No NCHAR006C NCHAR006C NCHAR007C NCHAR007C NCHAR008C NCHAR008C NCHAR009C NCHAR009C NCHAR010C NCHAR010C NCHAR011C NCHAR011C NCHAR012C NCHAR012C NCHAR013C NCHAR013C NCHAR014C NCHAR014C NCHAR015C NCHAR015C NCHAR016C NCHAR016C NCHAR017C NCHAR017C NCHAR018C NCHAR018C NCHAR019C NCHAR019C NCHAR020C NCHAR020C NCHAR021C NCHAR021C NCHAR022C NCHAR022C NCHAR024C NCHAR024C NCHAR026C NCHAR026C NCHAR028C NCHAR028C NCHAR030C NCHAR030C NCHAR032C NCHAR032C NCHAR034C NCHAR034C [ Remaks ] 1. Bounday dimensions of this beaing ae the same as those of the 7000 seies. 2. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(2) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page 219. Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings

85 1. Angula contact ball beaings 3NCHAR000CA seies Contact angle 20 Ceamic beaings B 2 B 2 B 2 B 1 b Static equivalent load P 0=X 0 F +Y 0 F a ud ud ud a ud a a 1 a 2 ud b ud a ud a ud a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0>F. Dynamic equivalent load P =XF +YF a a Back-to-back (DB) Face-to-face (DF) Tandem (DT) Contact angle Single ow/tandem F a Back-to-back/Face-to-face F F e e a > e e a > e F F F F X Y X Y X Y X Y F a Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No NCHAR006CA NCHAR006CA NCHAR007CA NCHAR007CA NCHAR008CA NCHAR008CA NCHAR009CA NCHAR009CA NCHAR010CA NCHAR010CA NCHAR011CA NCHAR011CA NCHAR012CA NCHAR012CA NCHAR013CA NCHAR013CA NCHAR014CA NCHAR014CA NCHAR015CA NCHAR015CA NCHAR016CA NCHAR016CA NCHAR017CA NCHAR017CA NCHAR018CA NCHAR018CA NCHAR019CA NCHAR019CA NCHAR020CA NCHAR020CA NCHAR021CA NCHAR021CA NCHAR022CA NCHAR022CA NCHAR024CA NCHAR024CA NCHAR026CA NCHAR026CA NCHAR028CA NCHAR028CA NCHAR030CA NCHAR030CA NCHAR032CA NCHAR032CA NCHAR034CA NCHAR034CA [ Remaks ] 1. Bounday dimensions of this beaing ae the same as those of the 7000 seies. 2. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(2) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page 219. Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings

86 1. Angula contact ball beaings 3NCHAR000 seies Contact angle 30 Ceamic beaings B 2 B 2 B 2 B 1 b Static equivalent load P 0=X 0 F +Y 0 F a ud ud ud a ud a a 1 a 2 ud b ud a ud a ud a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0<F. Dynamic equivalent load P =XF +YF a a Back-to-back (DB) Face-to-face (DF) Tandem (DT) Contact angle Single ow/tandem F a Back-to-back/Face-to-face F F e e a > e e a > e F F F F X Y X Y X Y X Y F a Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR NCHAR034 [ Remaks ] 1. Bounday dimensions of this beaing ae the same as those of the 7000 seies. 2. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(2) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page 219. Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings

87 1. Angula contact ball beaings Ceamic beaings 3NCHAC900C seies Contact angle 15 B 1 2 B 2 B 2 B b Static equivalent load P 0=X 0 F +Y 0 F a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0<F. Dynamic equivalent load P =XF +YF a ud ud a 1 a 2 ud a ud a ud b ud a ud a ud a Contact angle 1 if 0F a C0 e Single ow/tandem F a F e a > e F F Back-to-back/Face-to-face F a F e a > e F X Y X Y X Y X Y F a Back-to-back (DB) Face-to-face (DF) Tandem (DT) ) Fo i, use 2 fo DB & DF and 1 fo single & DT. Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Facto f 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No NCHAC900C NCHAC900C NCHAC901C NCHAC901C NCHAC902C NCHAC902C NCHAC903C NCHAC903C NCHAC904C NCHAC904C NCHAC905C NCHAC905C NCHAC906C NCHAC906C NCHAC907C NCHAC907C NCHAC908C NCHAC908C NCHAC909C NCHAC909C NCHAC910C NCHAC910C NCHAC911C NCHAC911C NCHAC912C NCHAC912C NCHAC913C NCHAC913C NCHAC914C NCHAC914C NCHAC915C NCHAC915C NCHAC916C NCHAC916C NCHAC917C NCHAC917C NCHAC918C NCHAC918C NCHAC919C NCHAC919C NCHAC920C NCHAC920C NCHAC921C NCHAC921C NCHAC922C NCHAC922C NCHAC924C NCHAC924C NCHAC926C NCHAC926C NCHAC928C NCHAC928C NCHAC930C NCHAC930C NCHAC932C NCHAC932C NCHAC934C NCHAC934C [ Remaks ] 1. Bounday dimensions of this beaing ae the same as those of the 7900 seies. 2. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(3) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page 219. Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings

88 1. Angula contact ball beaings 3NCHAC900CA seies Contact angle 20 Ceamic beaings B 2 B 2 B 2 B 1 b ud ud a 1 a 2 ud a ud a ud b ud a ud a ud a Static equivalent load P 0=X 0 F +Y 0 F a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0>F. Dynamic equivalent load P =XF +YF a a Back-to-back (DB) Face-to-face (DF) Tandem (DT) Contact angle Single ow/tandem F a Back-to-back/Face-to-face F F e e a > e e a > e F F F F X Y X Y X Y X Y F a Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No NCHAC900CA NCHAC900CA NCHAC901CA NCHAC901CA NCHAC902CA NCHAC902CA NCHAC903CA NCHAC903CA NCHAC904CA NCHAC904CA NCHAC905CA NCHAC905CA NCHAC906CA NCHAC906CA NCHAC907CA NCHAC907CA NCHAC908CA NCHAC908CA NCHAC909CA NCHAC909CA NCHAC910CA NCHAC910CA NCHAC911CA NCHAC911CA NCHAC912CA NCHAC912CA NCHAC913CA NCHAC913CA NCHAC914CA NCHAC914CA NCHAC915CA NCHAC915CA NCHAC916CA NCHAC916CA NCHAC917CA NCHAC917CA NCHAC918CA NCHAC918CA NCHAC919CA NCHAC919CA NCHAC920CA NCHAC920CA NCHAC921CA NCHAC921CA NCHAC922CA NCHAC922CA NCHAC924CA NCHAC924CA NCHAC926CA NCHAC926CA NCHAC928CA NCHAC928CA NCHAC930CA NCHAC930CA NCHAC932CA NCHAC932CA NCHAC934CA NCHAC934CA [ Remaks ] 1. Bounday dimensions of this beaing ae the same as those of the 7900 seies. 2. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(3) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page 219. Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings

89 1. Angula contact ball beaings Ceamic beaings 3NCHAC000C seies Contact angle 15 B 1 2 B 2 B 2 B b Static equivalent load P 0=X 0 F +Y 0 F a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0<F. Dynamic equivalent load P =XF +YF a ud ud a 1 a 2 ud a ud a ud b ud a ud a ud a Contact angle 1 if 0F a C0 e Single ow/tandem F a F e a > e F F Back-to-back/Face-to-face F a F e a > e F X Y X Y X Y X Y F a Back-to-back (DB) Face-to-face (DF) Tandem (DT) ) Fo i, use 2 fo DB & DF and 1 fo single & DT. Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Facto f 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No NCHAC000C NCHAC000C NCHAC001C NCHAC001C NCHAC002C NCHAC002C NCHAC003C NCHAC003C NCHAC004C NCHAC004C NCHAC005C NCHAC005C NCHAC006C NCHAC006C NCHAC007C NCHAC007C NCHAC008C NCHAC008C NCHAC009C NCHAC009C NCHAC010C NCHAC010C NCHAC011C NCHAC011C NCHAC012C NCHAC012C NCHAC013C NCHAC013C NCHAC014C NCHAC014C NCHAC015C NCHAC015C NCHAC016C NCHAC016C NCHAC017C NCHAC017C NCHAC018C NCHAC018C NCHAC019C NCHAC019C NCHAC020C NCHAC020C NCHAC021C NCHAC021C NCHAC022C NCHAC022C NCHAC024C NCHAC024C NCHAC026C NCHAC026C NCHAC028C NCHAC028C NCHAC030C NCHAC030C NCHAC032C NCHAC032C NCHAC034C NCHAC034C [ Remaks ] 1. Bounday dimensions of this beaing ae the same as those of the 7000 seies. 2. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(3) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page 219. Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings

90 1. Angula contact ball beaings 3NCHAC000CA seies Contact angle 20 Ceamic beaings B 2 B 2 B 2 B 1 b ud ud a 1 a 2 ud a ud a ud b ud a ud a ud a Static equivalent load P 0=X 0 F +Y 0 F a Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0>F. Dynamic equivalent load P =XF +YF a a Back-to-back (DB) Face-to-face (DF) Tandem (DT) Contact angle Single ow/tandem F a Back-to-back/Face-to-face F F e e a > e e a > e F F F F X Y X Y X Y X Y F a Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Intespace volume (cm 3 /ow) (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a D a D b b min. max. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No NCHAC000CA NCHAC000CA NCHAC001CA NCHAC001CA NCHAC002CA NCHAC002CA NCHAC003CA NCHAC003CA NCHAC004CA NCHAC004CA NCHAC005CA NCHAC005CA NCHAC006CA NCHAC006CA NCHAC007CA NCHAC007CA NCHAC008CA NCHAC008CA NCHAC009CA NCHAC009CA NCHAC010CA NCHAC010CA NCHAC011CA NCHAC011CA NCHAC012CA NCHAC012CA NCHAC013CA NCHAC013CA NCHAC014CA NCHAC014CA NCHAC015CA NCHAC015CA NCHAC016CA NCHAC016CA NCHAC017CA NCHAC017CA NCHAC018CA NCHAC018CA NCHAC019CA NCHAC019CA NCHAC020CA NCHAC020CA NCHAC021CA NCHAC021CA NCHAC022CA NCHAC022CA NCHAC024CA NCHAC024CA NCHAC026CA NCHAC026CA NCHAC028CA NCHAC028CA NCHAC030CA NCHAC030CA NCHAC032CA NCHAC032CA NCHAC034CA NCHAC034CA [ Remaks ] 1. Bounday dimensions of this beaing ae the same as those of the 7000 seies. 2. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(3) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page 219. Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings

91 1. Angula contact ball beaings 3NCHAD000CA seies Contact angle 20 Ceamic beaings B 2 B 2 B 2 B 1 b 2 c Static equivalent load P 0=X 0 F +Y 0 F a ud ud a 1 a 2 ud a ud b ud a ud b ud a ud a ud b Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0>F. Dynamic equivalent load P =XF +YF a a Back-to-back (DB) Face-to-face (DF) Tandem (DT) Contact angle Single ow/tandem F a Back-to-back/Face-to-face F F e e a > e e a > e F F F F X Y X Y X Y X Y F a Bounday dimensions d D B 1 2 min. min. min. Beaing No. Basic load atings (kn) C C 0 Limiting speeds (min 1 ) Oil lub. Load cente a (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Mounting dimensions d a d b D a D b b min. min. max. max. max. max. c max. Nut axial tension (N) Intefeence of etaining plate Beaing No NCHAD007CA NCHAD007CA NCHAD008CA NCHAD008CA NCHAD009CA NCHAD009CA NCHAD010CA NCHAD010CA NCHAD011CA NCHAD011CA NCHAD012CA NCHAD012CA NCHAD013CA NCHAD013CA NCHAD014CA NCHAD014CA NCHAD015CA NCHAD015CA NCHAD016CA NCHAD016CA NCHAD017CA NCHAD017CA NCHAD018CA NCHAD018CA NCHAD019CA NCHAD019CA NCHAD020CA NCHAD020CA NCHAD021CA NCHAD021CA NCHAD022CA NCHAD022CA NCHAD024CA NCHAD024CA NCHAD026CA NCHAD026CA [ Remaks ] 1. Bounday dimensions of this beaing ae the same as those of the 7000 seies. 2. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(4) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page 219. These beaings ae useful only with oil / ai lubication. Please use with lubicating spaces as shown below. Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings. Oil supply Oil dischage Oil supply Oil supply Lubicating spaces Lubicating spaces

92 1. Angula contact ball beaings 3NCHAF900CA seies Contact angle 20 Ceamic beaings B 2 B 2 B 2 B 1 b b 1 b Static equivalent load P 0=X 0 F +Y 0 F a ud ud a 1 a 2 S W ud a ud b ud a ud a ud a ud a ud b Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0>F. Dynamic equivalent load P =XF +YF a a Back-to-back (DB) Face-to-face (DF) Tandem (DT) Oil goove Contact angle Single ow/tandem F a Back-to-back/Face-to-face F F e e a > e e a > e F F F F X Y X Y X Y X Y F a Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Limiting speeds (min 1 ) Oil lub. Load cente a (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Oil goove dimensions S W Mounting dimensions d a d b D a b min. min. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No NCHAF908CA NCHAF908CA NCHAF909CA NCHAF909CA NCHAF910CA NCHAF910CA NCHAF911CA NCHAF911CA NCHAF912CA NCHAF912CA NCHAF913CA NCHAF913CA NCHAF914CA NCHAF914CA NCHAF915CA NCHAF915CA NCHAF916CA NCHAF916CA NCHAF917CA NCHAF917CA NCHAF918CA NCHAF918CA NCHAF919CA NCHAF919CA NCHAF920CA NCHAF920CA NCHAF921CA NCHAF921CA NCHAF922CA NCHAF922CA NCHAF924CA NCHAF924CA NCHAF926CA NCHAF926CA [ Remaks ] 1. Bounday dimensions of this beaing ae the same as those of the 7900 seies. 2. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(5) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page 219. Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings. These beaings ae useful only with oil / ai lubication. Please use with lubicating spaces as shown below. Oil supply Oil supply Oil dischage Oil supply Oil supply Oil supply Oil supply Lubicating spaces Lubicating spaces

93 1. Angula contact ball beaings 3NCHAF000CA seies Contact angle 20 Ceamic beaings B 2 B 2 B 2 B 1 b b 1 b Static equivalent load P 0=X 0 F +Y 0 F a ud ud a 1 a 2 S W ud a ud b ud a ud a ud a ud a ud b Contact angle Single ow/ Tandem Back-to-back/ Face-to-face X 0 Y 0 X 0 Y Note that in the case of single ow o tandem, assume P 0=F if P 0>F. Dynamic equivalent load P =XF +YF a a Back-to-back (DB) Face-to-face (DF) Tandem (DT) Oil goove Contact angle Single ow/tandem F a Back-to-back/Face-to-face F F e e a > e e a > e F F F F X Y X Y X Y X Y F a Bounday dimensions d D B 1 min. min. Beaing No. Basic load atings (kn) C C 0 Limiting speeds (min 1 ) Oil lub. Load cente a (Refe.) Mass (kg/ow) Pemissible axial loads (kn) (static) Load cente spead of pai-mounted beaings a 1 a 2 Oil goove dimensions S W Mounting dimensions d a d b D a b min. min. max. max. max. Nut axial tension (N) Intefeence of etaining plate Beaing No NCHAF006CA NCHAF006CA NCHAF007CA NCHAF007CA NCHAF008CA NCHAF008CA NCHAF009CA NCHAF009CA NCHAF010CA NCHAF010CA NCHAF011CA NCHAF011CA NCHAF012CA NCHAF012CA NCHAF013CA NCHAF013CA NCHAF014CA NCHAF014CA NCHAF015CA NCHAF015CA NCHAF016CA NCHAF016CA NCHAF017CA NCHAF017CA NCHAF018CA NCHAF018CA NCHAF019CA NCHAF019CA NCHAF020CA NCHAF020CA NCHAF021CA NCHAF021CA NCHAF022CA NCHAF022CA [ Remaks ] 1. Bounday dimensions of this beaing ae the same as those of the 7000 seies. 2. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(5) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page 219. Basic load atings in case of multiple-ow combination beaing Basic dynamic load atings C 1.62 Basic static load atings 2-ow C ow C 2.16 C ow C 2.64 C 0 4 Speed coefficients in case of multiple-ow combination beaing Combination Combination Peload when mounting types symbols Peload S Peload L Peload M Peload H DB DBB DBD *Speed coefficients also vay depending on the distance of beaings. These beaings ae useful only with oil / ai lubication. Please use with lubicating spaces as shown below. Oil supply Oil supply Oil dischage Oil supply Oil supply Oil supply Oil supply Lubicating spaces Lubicating spaces

94

95 2. Cylindical Rolle Beaings Contents Page 2. 1 Types and featues of cylindical olle beaings Composition of beaing numbes Toleance of cylindical olle beaings Radial intenal cleaances of cylindical olle beaings 125 Beaing dimension tables NN3000(K) seies 126 NNU4900(K) seies 128 N1000(K) seies 130 3NCN1000(K) seies

96

97 2. Cylindical olle beaings The cylindical olle beaing has high adial igidity and is suitable fo high-speed otation though an aangement of many olles and a line contact which is made between the olles and aceways. The boes of cylindical olle beaings ae eithe cylindical o tapeed. With a beaing having a tapeed boe, its adial intenal cleaance can be set with ease to a given value by adjusting the extent to which the beaing is pushed onto the shaft Types and featues of cylindical olle beaings The cylindical olle beaing is divided into two types: double ow and single ow beaings. Both having oute ing which is sepaable fom the inne to facilitate mounting and dismounting fom shaft and housing (see Fig. 2. 1). 1) Double ow cylindical olle beaings The double ow cylindical olle beaing is classified into the NN30 and NNU49 seies. Some of these beaings have a lubication goove and holes povided at the cente of the outside suface of the oute ings in ode to attain a sufficient supply of lubicant to the inside of the beaing (the suffix W is added). 2) Single ow cylindical olle beaings Single ow cylindical olle beaings fo the spindles of machine tools ae often selected fom the N10 seies. The boe and outside diametes of the N10 seies ae the same as those of the NN30: double ow cylindical olle beaing seies. Cylindical boe Tapeed boe With a lubication goove and holes Cylindical boe Tapeed boe With a lubication goove and holes Cylindical boe Tapeed boe Beaing seies NN3000 NN3000K NN3000W NNU4900 NNU4900K NNU4900W N1000 NN3000KW NNU4900KW 3NCN1000 Fig Types and seies of cylindical olle beaings fo machine tool spindles N1000K 3NCN1000K 2. 2 Composition of beaing numbes (cylindical olle beaings) N N K W C 1 N A F W P 4 N C 1 N A F Y P 4 Beaing type symbols NN : double ow/ inne ing with ib NNU : double ow/ oute ing with ib N : single ow/ inne ing with ib Dimension seies symbols 30 : dimension seies : dimension seies : dimension seies 10 Boe diamete numbe 09 : nominal boe diamete : 45 mm (Boe diamete numbe 5 equals nominal boe diamete.) Ring shape symbols K : beaing with tapeed boe (1/12 tape) W : oute ing with a lubication goove and holes Toleance class symbols P5 : JIS class 5 P4 : JIS class 4 P2 : JIS class 2 Cage symbols FW : sepaable machined cage made of coppelloy FY : integated machined cage made of coppelloy (Double ow beaing) Machined cage made of coppelloy with ivets (single ow beaing) FG : molded cage made of polyamide esin (Consult JTEKT fo detailed infomation about the available types.) Intenal cleaance symbols C9NA adial intenal cleaance of ~C3NA : non-intechangeable beaings Fo values of adial intenal cleaances, see Table 2. 2 (page 125). Fo ceamic beaings 3 N C N C 1 N A F Y P 4 Ceamic beaing 123

98 2. Cylindical olle beaings 2. 3 Toleance of cylindical olle beaings 1) Bounday dimension and unning accuacies The toleance of pecision cylindical olle beaings is compliant with pemissible dimensional deviations and limits of classes 5, 4, and 2 as specified in JIS B 1514 fo adial beaings (tapeed olle beaings not included). Pemissible dimensional deviations and limits to bounday dimension and unning accuacies ae shown in Table 1. 2 on page 56. 2) Pemissible dimensional deviations and limits fo tapeed boes The dimensional deviations and limits fo tapeed boes of adial beaings of class 0 only ae specified in JIS B JTEKT has fomulated special standads fo dimensional deviations and limits fo tapeed boes of adial beaings of classes 5, 4, and 2 (see Table 2. 1). Table 2. 1 Dimensional deviations and limits fo tapeed boes of adial beaings (classes 5, 4, and 2) α α 3 d1mp 3 dmp 2 u d Tape atio 1 12 u d 1 u (d + 3 dmp) u (d d1mp) B Theoetical tapeed boe B Tapeed boe with single plane mean boe diamete deviation 3 dmp 1) Nominal boe diamete 3 d1mp 3 dmp Diamete seies 9 Diamete seies d Class 5 Classes 4, 2 Classes 5, 4, 2 Class 5 Class 4 Class 5 Class 4 Class 2 ove up to uppe lowe uppe lowe uppe lowe max. max. max [ Notes ] 1) Pemissible dimensional deviation fo the tapengle is 4 46'18.8 "+26" 0 2) Applied to all adial planes of tapeed boes. [ Remaks ] 1. Scope These values ae applied to the tapeed boes with a efeence tape atio of 1/ Symbols fo quantities d 1 1 : efeence diametet theoetical lage end of tapeed boe d 1= d B 12 3 dmp : single plane mean boe diamete deviation at theoetical small end of tapeed boe 3 d1mp : single plane mean boe diamete deviation at theoetical lage end of tapeed boe V dsp : single plane boe diamete vaiation B : nominal inne ing width α : of the nominal tapengle of tapeed boe 2 α =2 23'9.4" = = ad V dsp 2) Unit : μm 124

99 2. 4 Radial intenal cleaances of cylindical olle beaings In ode to minimize vaiations in the unning accuacy of machine tool spindles, the values of the adial intenal cleaance should be same as those of special adial intenal cleaance of nonintechangeable beaings. Table 2. 2 shows values of non-intechangeable adial intenal cleaances fo cylindical olle beaings. Since the innend oute ings of cylindical olle beaings fo spindles of machine tools ae not intechangeable, cae should be taken when using them. Table 2. 2 Values of adial intenal cleaances fo cylindical olle beaings (1) Beaings with cylindical boes (2) Beaings with tapeed boes Unit : μm Unit : μm Nominal boe diamete d Values of non-intechangeable cleaances of beaings with cylindical boes C1NA C2NA CNNA C3NA Nominal boe diamete d Values of non-intechangeable cleaances of beaings with tapeed boes C9NA 1) C0NA C1NA C2NA CNNA C3NA ove up to min. max. min. max. min. max. min. max ove up to min. max. min. max. min. max. min. max. min. max. min. max [ Note ] 1) The cleaance C9NA is applied to cylindical olle beaings with tapeed boes made to JIS toleance classes 5 and

100 2. Cylindical olle beaings NN3000(K) seies Cylindical boe Tapeed boe B w ud 0 ue w ud ud ud ud a ud a Tape 1 12 Bounday dimensions d D B E w min. Cylindical boe Beaing No. 1) With a lubication 1) goove and holes Tapeed boe Basic load atings (kn) C C 0 With a lubication 1) goove and holes Limiting speeds (min 1 ) Gease Oil lub. lub. Dimensions of lubication goove and holes d 0 w Mounting dimensions Intespace volume d a D a (cm 3 ) min. max. min. max. Dynamic equivalent load P =F Static equivalent load P 0=F Cylindical boe (Refe.)Mass (kg) Tapeed boe NN3005 NN3005K NN3006 NN3006K NN3007 NN3007K NN3008 NN3008K NN3009 NN3009K NN3010 NN3010K NN3011 NN3011K NN3012 NN3012K NN3013 NN3013K NN3014 NN3014K NN3015 NN3015K NN3016 NN3016K NN3017 NN3017K NN3018 NN3018K NN3019 NN3019K NN3020 NN3020K NN3021 NN3021K NN3022 NN3022K NN3024 NN3024K NN3026 NN3026K NN3028 NN3028K NN3030 NN3030K NN3032 NN3032K NN3034 NN3034K NN3036 NN3036K NN3038 NN3038K NN3040 NN3040K NN3044 NN3044K NN3048 NN3048K NN3052 NN3052K NN3056 NN3056K NN3060 NN3060K NN3064 NN3064K NN3068 NN3068K NN3072 NN3072K NN3076 NN3076K NN3080 NN3080K [ Note ] 1) The symbol W is added to the end of beaing numbes to denote beaings whose oute ing has a lubication goove and holes. [ Remaks ] 1. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(6) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page

101 2. Cylindical olle beaings NNU4900(K) seies Cylindical boe Tapeed boe B w ud 0 uf w ud ud ud ud a ud a ud a ud b Tape 1 12 Bounday dimensions d D B F w min. Cylindical boe Beaing No. 1) With a lubication 1) goove and holes Tapeed boe Basic load atings (kn) C C 0 With a lubication 1) goove and holes Limiting speeds (min 1 ) Gease Oil lub. lub. Dimensions of lubication goove and holes d 0 w Mounting dimensions Intespace volume d a d b D a (cm 3 ) min. max. min. max. max. Dynamic equivalent load P =F Static equivalent load P 0=F Cylindical boe (Refe.)Mass (kg) Tapeed boe NNU4920 NNU4920K NNU4921 NNU4921K NNU4922 NNU4922K NNU4924 NNU4924K NNU4926 NNU4926K NNU4928 NNU4928K NNU4930 NNU4930K NNU4932 NNU4932K NNU4934 NNU4934K NNU4936 NNU4936K NNU4938 NNU4938K NNU4940 NNU4940K NNU4944 NNU4944K NNU4948 NNU4948K NNU4952 NNU4952K NNU4956 NNU4956K NNU4960 NNU4960K NNU4964 NNU4964K NNU4968 NNU4968K [ Note ] 1) The symbol W is added to the end of beaing numbes to denote beaings whose oute ing has a lubication goove and holes

102 2. Cylindical olle beaings N1000(K) seies B 1 1 b ue w ud ud ud ud b ud a ud b Tape 1 12 Bounday dimensions Cylindical boe d D B 1 E w min. min. Cylindical boe Beaing No. Tapeed boe Tapeed boe Basic load atings (kn) C C 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Mounting dimensions d a D b b min. max. min. max. max. Dynamic equivalent load P =F Static equivalent load P 0=F Intespace volume (cm 3 ) Cylindical boe (Refe.)Mass (kg) Tapeed boe N1006 N1006K N1007 N1007K N1008 N1008K N1009 N1009K N1010 N1010K N1011 N1011K N1012 N1012K N1013 N1013K N1014 N1014K N1015 N1015K N1016 N1016K N1017 N1017K N1018 N1018K N1019 N1019K N1020 N1020K N1021 N1021K N1022 N1022K N1024 N1024K N1026 N1026K N1028 N1028K N1030 N1030K N1032 N1032K [ Remaks ] 1. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(6) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page

103 2. Cylindical olle beaings 3NCN1000(K) seies Ceamic beaings B 1 1 b ue w ud ud ud ud b ud a ud b Tape 1 12 Bounday dimensions Cylindical boe d D B 1 E w min. min. Cylindical boe Beaing No. Tapeed boe Tapeed boe Basic load atings (kn) C C 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Mounting dimensions d a D b b min. max. min. max. max. Dynamic equivalent load P =F Static equivalent load P 0=F Intespace volume (cm 3 ) Cylindical boe (Refe.)Mass (kg) Tapeed boe NCN1006 3NCN1006K NCN1007 3NCN1007K NCN1008 3NCN1008K NCN1009 3NCN1009K NCN1010 3NCN1010K NCN1011 3NCN1011K NCN1012 3NCN1012K NCN1013 3NCN1013K NCN1014 3NCN1014K NCN1015 3NCN1015K NCN1016 3NCN1016K NCN1017 3NCN1017K NCN1018 3NCN1018K NCN1019 3NCN1019K NCN1020 3NCN1020K NCN1021 3NCN1021K NCN1022 3NCN1022K NCN1024 3NCN1024K NCN1026 3NCN1026K NCN1028 3NCN1028K NCN1030 3NCN1030K NCN1032 3NCN1032K [ Remaks ] 1. Fo the dimensions of the spaces fo oil / ai lubication, efe to Table 9. 4(6) on page Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page

104

105 3. Angula Contact Ball Beaings fo Axial Load Contents Page 3. 1 Types and featues of angula contact ball beaings foxial load Composition of beaing numbes Toleance of angula contact ball beaings foxial load Standad peloads fo high-speed matched paingula contact ball beaings Axial load and displacement 143 Beaing dimension tables B and B seies B and B seies 148 ACT000DB seies 150 ACT000BDB seies

106

107 3. Angula contact ball beaings foxial load JTEKT poduces double diection angula contact thust and high-speed matched paingula contact ball beaings to eceive the axial loads fom spindles of machine tools Types and featues of angula contact ball beaings foxial load Table 3. 1 Types and featues of angula contact ball beaings foxial load Type Diamete seies 0 9 Featues Double diection angula contact thust ball beaings High-speed matched pai angula contact ball beaings B ACT 0 DB ACT 0 BDB 2347 B B B Axial load can be applied in both Negative toleances on the outside diections, and the igidity in the diametes ae used to pemit axial axial diection is high. load only. Beaings having geate contact Having small contact angles, these angles ae moe suitable whee ae suitable fo high-speed igidity is a pioity, and those otations. having smalle contact angles ae These beaings ae moe appopiate whee highspeed intechangeable with 2344 B seies. pefomance is a pioity. To combine with double ow cylindical olle beaings Remak: These beaings ae used pimaily in combination with double ow cylindical olle beaings fo adial load. Combinations ae as shown below. Placed next to the small tapeed boe diamete side of NN30K, o used in tandem with NN30 (cylindical boe). Placed next to the lage tapeed boe diamete side of NN30K. Placed next to the small tapeed boe diamete side of NNU49K, o used in tandem with NNU49 (cylindical boe). Placed next to the lage tapeed-boe diamete side of NNU49K C 1 2B Intechangeability Space A Space A' Example of mounting in Example of mounting in tandem with 2344 B tandem with ACT 0 DB o ACT 0 BDB Since the combined width "2B" of ACT 0 DB and ACT 0 BDB is equal to dimension "C 1" of 2344 B, it is not necessay to change shaft and housing dimensions. Changing the width of space A is sufficient. 137

108 3. Angula contact ball beaings foxial load 3. 2 Composition of beaing numbes (angula contact ball beaings foxial load) Double diection angula contact thust ball beaings B FY P4 Double diection angula contact thust ball beaings Toleance class symbols P5 : equivalent of JIS class 5 P4 : equivalent of JIS class 4 Contact angle symbols 3 : nominal contact angle 60 Cage symbols FY : machined cage made of coppelloy Diamete seies symbols 4 : diamete seies 0 9 : diamete seies 9 Oute ing configuation symbols B : integated oute ing type Beaing boe diamete classification symbols 4 : small boe diamete type 7 : lage boe diamete type Boe diamete numbes 18 : nominal boe diamete 90 mm (Boe diamete numbe 5 equals nominal boe diamete.) High-speed matched paingula contact ball beaings ACT 0 18 B DB M FT P4 High-speed matched paingula contact ball beaings Toleance class symbols P5 : equivalent of JIS class 5 P4 : equivalent of JIS class 4 Diamete seies 0 Boe diamete numbe 18 : nominal boe diamete 90 mm (Boe diamete numbe 5 equals nominal boe diamete.) Cage symbols FG : molded cage made of polyamide esin (ball-guiding type) FT : machined cage made of einfoced phenolic esin (oute ing-guiding type) FY : machined cage made of coppe alloy (oute ing-guiding type) Contact angle symbols A (to be omitted) : nominal contact angle 30 B : nominal contact angle 40 Back-to-back symbol Peload symbols L : light peload M : medium peload (See Table 3. 4 (page 142) fo peload values.) 138

109 3. 3 Toleance of angula contact ball beaings foxial load The toleance of double diection angula contact thust ball beaings is shown in Table The toleance of high-speed matched paingula contact ball beaings is shown in Table 3. 3 (page 140 and 141). The toleance of these beaings complies with JTEKT standads Classes 5 and 4 (equivalent of JIS Classes 5 and 4). Table 3. 2 Pemissible dimensional deviations and limits to double diection angula contact thust ball beaings (JTEKT standads) (1) Inne ing and assembled beaing width Unit : μm Nominal boe diamete d 3 dmp o 3 ds 1) Actual beaing width deviation 3 Ts Inne ing width vaiation V Bs Pependiculaity of inne ing face with espect to the boe S d Axial unout of assembled beaing inne ing S ia Class 5 Class 4 Classes 5, 4 Class 5 Class 4 Class 5 Class 4 Class 5 Class 4 ove up to uppe lowe uppe lowe uppe lowe max. max. max (2) Oute ing Unit : μm Nominal outside 2) diamete 3 Dmp o 3 Ds D Classes 5, 4 ove up to uppe lowe Oute ing width vaiation V Cs Pependiculaity of oute ing outside suface with espect to the face S D Axial unout of assembled beaing oute ing S ea Class 5 Class 4 Class 5 Class 4 Classes 5, 4 max. max. max [ Notes ] 1) Single plane mean boe diamete deviation o single boe diamete deviation 2) Single plane mean outside diamete deviation o single outside diamete deviation Same as pemissible values S ia, d being that of the same beaing. T ud ud d : nominal boe diamete D : nominal outside diamete T : nominal beaing width 139

110 3. Angula contact ball beaings foxial load Table 3. 3(1) Pemissible dimensional deviations and limits of high-speed matched pai angula contact ball beaings (JTEKT standads) (1) Inne ing Unit : μm Nominal boe diamete d Single plane mean boe diamete deviation 3 dmp Single boe diamete deviation 3 ds 1) Single plane boe diamete vaiation Diamete seies 9 Diamete seies 0 Mean boe diamete vaiation V dmp Class 5 Class 4 Class 4 Class 5 Class 4 Class 5 Class 4 Class 5 Class 4 ove up to uppe lowe uppe lowe uppe lowe max. max. max V dsp Nominal boe diamete d Radial unout of assembled beaing inne ing K ia Pependiculaity of inne ing face with espect to the boe S d Axial unout of assembled beaing inne ing S ia Single inne ing width deviation 3 Bs Single inne ing width deviation 3 Bs 2) Inne ing width vaiation Class 5 Class 4 Class 5 Class 4 Class 5 Class 4 Classes 5, 4 Classes 5, 4 Class 5 Class 4 ove up to max. max. max. uppe lowe uppe lowe max [ Notes ] 1) Toleance class 4 is applied to beaings of diamete seies 0. 2) Applied to individual beaing ings manufactued fo matched pai o stack beaings. V Bs B ud ud d : nominal boe diamete D : nominal outside diamete B : nominal beaing width 140

111 Table 3. 3(2) Pemissible dimensional deviations and limits fo high-speed matched pai angula contact ball beaings (JTEKT standads) (2) Oute ing Unit : μm Nominal outside diamete D 3 Dmp o 3 Ds 1), 2) Single plane outside diamete vaiation V Dsp Diamete seies Diamete seies 9 0 Classes 5, 4 Class 5 Class 4 Class 5 Class 4 Class 5 Class 4 ove up to uppe lowe max. max. max Mean outside diamete vaiation V Dmp Nominal outside diamete D Radial unout of assembled beaing oute ing K ea Pependiculaity of oute ing out side suface with espect to the face S D Axial unout of assembled beaing oute ing S ea Deviation of a single oute ing width 3 Cs Ring width vaiation V Cs Class 5 Class 4 Class 5 Class 4 Class 5 Class 4 Classes 5, 4 Class 5 Class 4 ove up to max. max. max. uppe lowe max Same as 8 5 toleance 3 Bs, d being that of the same beaing [ Notes ] 1) Single plane mean outside diamete deviation o single outside diamete deviation 2) Dimensional toleance fo outside diamete of class 4 is applied to beaings of diamete seies 0. B ud ud d : nominal boe diamete D : nominal outside diamete B : nominal beaing width 141

112 3. Angula contact ball beaings foxial load 3. 4 Standad peloads fo high-speed matched paingula contact ball beaings Table 3. 4 shows standad peloads fo high-speed matched paingula contact ball beaings. Table 3. 4 Standad peloads fo high-speed matched pai angula contact ball beaings (L : light peload; M : medium peload) Unit : N Boe diamete ACT 000 ACT 000 B numbe L M L M

113 3. 5 Axial load and displacement (angula contact ball beaings foxial load) Fig show elationships between axial load and displacement espectively fo double diection angula contact thust and high-speed matched paingula contact ball beaings when a standad peload is applied. (1) B and B seies (contact angle : 60 ) (2) B and B seies (contact angle : 60 ) (µm) (Boe diamete numbe) (µm) (Boe diamete numbe) Axial displacement , , 18 20, Axial displacement Axial load (kn) Axial load (kn) Fig. 3. 1(1) Relationships between axial load and displacement (double diection angula contact thust ball beaings) 143

114 3. Angula contact ball beaings foxial load (3) ACT000 seies (contact angle 30 ) a) When peload L is applied (4) ACT000B seies (contact angle 40 ) a) When peload L is applied (µm) 14 (μm) 8 Axial displacement (Boe diamete numbe) Axial displacement (Boe diamete numbe) Axial load (kn) Axial load (kn) b) When peload M is applied b) When peload M is applied (μm) 12 (μm) 6 Axial displacement (Boe diamete numbe) Axial displacement (Boe diamete numbe) Axial load (kn) Axial load (kn) Fig. 3. 1(2) Relationships between axial load and displacement (high-speed matched paingula contact ball beaings) 144

115 145

116 3. Angula contact ball beaings foxial load B seies B seies Contact angle 60 T w 1 ud 0 b B ud ue w ud 1 ud ud a ud a C Dynamic equivalent load P a =F a Static equivalent load P 0a=F a Small boe dia. type d Lage boe dia. type Bounday dimensions D T C 1 min. min. Small boe dia. type Beaing No. 1) Lage boe dia. type Basic load atings (kn) C a C 0a Limiting speeds (min 1 ) Gease Oil lub. lub. E w 2 Dimensions d 1 B d 0 w Mounting dimensions d a D a b min. max. max. max. Amount of gease fill (cm 3 ow) (Refe.)Mass (kg) Small boe dia. type Lage boe dia. type B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B [ Notes ] 1) The small boe diamete type beaing is placed next to the small tapeed-boe diamete side of the NN30K, o used in tandem with NN30. The lage boe diamete type beaing is placed next to the lage tapeed-boe diamete side of NN30K. 2) The dimension E w is used as a efeence fo the ball set outside diamete

117 3. Angula contact ball beaings foxial load B seies B seies Contact angle 60 T w 1 ud 0 b B ud ue w ud 1 ud ud a ud a C Dynamic equivalent load P a =F a Static equivalent load P 0a=F a Small boe dia. type d Lage boe dia. type Bounday dimensions D T C 1 min. min. Small boe dia. type Beaing No. 1) Lage boe dia. type Basic load atings (kn) C a C 0a Limiting speeds (min 1 ) Gease Oil lub. lub. E w 2 Dimensions d 1 B d 0 w Mounting dimensions d a D a b min. max. max. max. Amount of gease fill (cm 3 ow) (Refe.)Mass (kg) Small boe dia. type Lage boe dia. type B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B B [ Notes ] 1) The small boe diamete type beaing is placed next to the small tapeed-boe diamete side of the NNU49K, o used in tandem with NNU49. The lage boe diamete type beaing is placed next to the lage tapeed-boe diamete side of NNU49K. 2) The dimension E w is used as a efeence fo the ball set outside diamete

118 3. Angula contact ball beaings foxial load ACT000DB seies Contact angle 30 2B b 1 1 ud ud ud a ud a a 1 Bounday dimensions d D 2B 1 min. min. Beaing No. Basic load atings (kn) C a C 0a Limiting speeds (min 1 ) Gease Oil lub. lub. Mounting dimensions d a D a b min. max. max. max ACT006DB ACT007DB ACT008DB ACT009DB ACT010DB ACT011DB ACT012DB ACT013DB ACT014DB ACT015DB ACT016DB ACT017DB ACT018DB ACT019DB ACT020DB ACT021DB ACT022DB ACT024DB ACT026DB ACT028DB ACT030DB ACT032DB ACT034DB ACT036DB ACT038DB ACT040DB ACT044DB ACT048DB ACT052DB ACT056DB ACT060DB ACT064DB [ Remak ] This beaing is intechangeable with B as thei boe and outside diametes ae the same. Pemissible axial loads (kn) static Load cente spead a 1 Dynamic equivalent load P a =F a Static equivalent load P 0a=F a Intespace volume (cm 3 ow) (Refe.) Mass (kg/ow)

119 3. Angula contact ball beaings foxial load ACT000BDB seies Contact angle B 1 b ud ud ud a ud a a 1 Bounday dimensions d D 2B 1 min. min. Beaing No. Basic load atings (kn) C a C 0a Limiting speeds (min 1 ) Gease Oil lub. lub. Mounting dimensions d a D a b min. max. max. max ACT006BDB ACT007BDB ACT008BDB ACT009BDB ACT010BDB ACT011BDB ACT012BDB ACT013BDB ACT014BDB ACT015BDB ACT016BDB ACT017BDB ACT018BDB ACT019BDB ACT020BDB ACT021BDB ACT022BDB ACT024BDB ACT026BDB ACT028BDB ACT030BDB ACT032BDB ACT034BDB ACT036BDB ACT038BDB ACT040BDB ACT044BDB ACT048BDB ACT052BDB ACT056BDB ACT060BDB ACT064BDB [ Remak ] This beaing is intechangeable with B as thei boe and outside diametes ae the same. Pemissible axial loads (kn) static Load cente spead a 1 Dynamic equivalent load P a =F a Static equivalent load P 0a=F a Intespace volume (cm 3 ow) (Refe.) Mass (kg/ow)

120

121 4. Tapeed Rolle Beaings Contents Page 4. 1 Types and featues of tapeed olle beaings Composition of beaing numbes Toleance of tapeed olle beaings Axial load and displacement 159 Beaing dimension tables 32900JR seies JR seies JR seies JR seies

122

123 4. Tapeed olle beaings The tapeed olle beaing is a beaing in which tapeed olles (tuncated conical olles) ae inseted between the oute ing and inne ing. The olles ae guided by the inne ing back face ib (see Fig. 4. 1). A adial load and an axial load can be simultaneously applied to the tapeed olle beaing. This beaing has high igidity. In addition, tapeed olle beaings allow easy adjustments of peload Types and featues of tapeed olle beaings Two types of tapeed olle beaings ae available fo machine tools: the single ow tapeed olle beaing (auxiliay symbol: JR) and the tapeed olle beaing with flanged oute ing (auxiliay symbol: B) (see Table 4. 1). Same as contact angle Inne ing cente Oute ing Oute ing angle Tapeed olle Load cente Inne ing back face ib Inne ing Contact angle (α) Fig Stuctue of tapeed olle beaing Since the single ow tapeed olle beaing can eceive only a unidiectional axial load, a pai of single ow beaings ae mounted apat and facing each othe, o they ae often used in a face-to-face o backto-back aangement. Table 4. 1 Types and featues of tapeed olle beaings fo machine tools Types Tapeed olle beaing with J designation Contact angle (α) Oute ing small inside diamete Oute ing width ISO sub-unit specifications Tapeed olle beaing with flanged oute ing Featues Beaings whose basic numbes ae followed by "J" ae made to the ISO sub-unit specifications. Consequently, inne ing assembles and oute ings, if given the same beaing numbe, ae intechangeable on an intenational level. Refeence: The symbol R denotes high load capacity beaings. This beaing allows easy positioning in axial diection using a simple housing stuctue Composition of beaing numbes (metic seies tapeed olle beaings) J R B P 5 Tapeed olle beaing Dimension seies symbol 29 : dimension seies : dimension seies : dimension seies : dimension seies 22 Toleance class symbol P5 : JIS class 5 P4 : JIS class 4 Oute ing shape symbol B : flanged oute ing No specified : standad type Boe diamete numbe 15 : nominal boe diamete 75 mm (Boe diamete numbe 5 equals nominal boe diamete.) High load capacity beaing Designed to ISO sub-unit 157

124 4. Tapeed olle beaings 4. 3 Toleance of tapeed olle beaings The toleance of the tapeed olle beaing is compliant with pemissible dimensional deviations and limits of classes 5 and 4 as specified in JIS B 1514 fo tapeed olle beaings. Pemissible dimensional deviations and limits to tapeed olle beaings ae shown in Table u D T C B u d d : nominal boe diamete D : nominal outside diamete B : nominal inne ing width C : nominal oute ing width T : nominal beaing width Table 4. 2 Pemissible dimensional deviations and limits to metic tapeed olle beaings (1) Inne ing Nominal boe diamete d Single plane mean boe diamete deviation 3 dmp Single boe diamete deviation 3 ds Single plane boe diamete vaiation V dsp Unit : μm Mean boe diamete vaiation V dmp Class 5 Class 4 Class 4 Class 5 Class 4 Class 5 Class 4 ove up to uppe lowe uppe lowe uppe lowe max. max Nominal boe diamete d Radial unout of assembled beaing inne ing K ia Face unout with boe S d Assembled beaing inne ing back face unout with aceway S ia Single inne ing width deviation Class 5 Class 4 Class 5 Class 4 Class 4 Classes 5, 4 Classes 5, 4 ove up to max. max. max. uppe lowe uppe lowe Bs Actual beaing width deviation 3 Ts (2) Oute ing Unit : μm Nominal Single plane mean Single outside Single adial plane Mean outside Radial unout of Vaiation of outside Assembled beaing Single oute ing outside outside diamete diamete outside diamete diametessembled suface geneatix oute ing back face width deviation diamete deviation deviation vaiation vaiation beaing oute ing inclination with face unout with aceway D 3 Dmp 3 Ds V Dsp V Dmp K ea S D S ea 3 Cs Class 5 Class 4 Class 4 Class 5 Class 4 Class 5 Class 4 Class 5 Class 4 Class 5 Class 4 Class 4 Classes 5, 4 ove up to uppe lowe uppe lowe uppe lowe max. max. max. max. max. uppe lowe Same as toleance Bs, d being that of the same beaing

125 4. 4 Axial load and displacement (tapeed olle beaings) Fig 4. 2 shows elationships between axial load and displacement of KOYO tapeed olle beaings. (1) 32900JR seies (2) 32000JR seies (μm) 20 Axial displacement (Boe diamete numbe) (μm) 20 Axial displacement (Boe diamete numbe) Axial load (kn) Axial load (kn) (3) 30200JR seies (4) 32200JR seies (μm) 20 Axial displacement (Boe diamete numbe) (μm) 20 Axial displacement (Boe diamete numbe) Axial load (kn) Axial load (kn) Fig Relationships between axial load and displacement (tapeed olle beaings) *The axial displacements shown above ae values of the single-ow beaings not peloaded. 159

126 4. Tapeed olle beaings 32900JR seies 32900JR T C JRB C 1 T 2 S a S b b B ud ud ud 1 ud a ud b ud a ud b Dynamic equivalent load P =XF +YF a F a F e a > e F F X Y X Y a Y 1 Static equivalent load P 0=0.5F +Y 0 F a Note that if P 0<F, it is assumed that P 0=F. Fo e, Y 1, and Y 0, use values given in the table. Bounday dimensions d D T B C 1 min. min. Beaing 1) No. Basic load atings (kn) C C 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Flange dimensions D 1 C 1 T 2 d a min. d b max. D a max. Mounting dimensions min. D b min. S a min. S b min. max. b max. Constant e Axial load coefficient Y 1 Y 0 (Refe.) Mass (kg) JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR [ Note ] 1) The beaing numbe of a tapeed olle beaing with a flanged oute ing contains the auxiliay symbol B. Example 32908JRB

127 4. Tapeed olle beaings 32000JR seies 32000JR 32000JRB S a S b 1 T C C 1 T 2 b B ud ud ud 1 ud a ud b ud a ud b Dynamic equivalent load P =XF +YF a F a F e a > e F F X Y X Y a Y 1 Static equivalent load P 0=0.5F +Y 0 F a Note that if P 0<F, it is assumed that P 0=F. Fo e, Y 1, and Y 0, use values given in the table. Bounday dimensions d D T B C 1 min. min. Beaing 1) No. Basic load atings (kn) C C 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Flange dimensions D 1 C 1 T 2 d a min. d b max. D a max. Mounting dimensions min. D b min. S a min. S b min. max. b max. Constant e Axial load coefficient Y 1 Y 0 (Refe.) Mass (kg) JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR [ Note ] 1) The beaing numbe of a tapeed olle beaing with a flanged oute ing contains the auxiliay symbol B. Example 32004JRB

128 4. Tapeed olle beaings 30200JR seies 30200JR 30200JRB 1 T C C 1 T 2 S a b S b ud B ud ud 1 ud a ud b ud a ud b Dynamic equivalent load P =XF +YF a F a F e a > e F F X Y X Y a Y 1 Static equivalent load P 0=0.5F +Y 0 F a Note that if P 0<F, it is assumed that P 0=F. Fo e, Y 1, and Y 0, use values given in the table. Bounday dimensions d D T B C 1 min. min. Beaing 1) No. Basic load atings (kn) C C 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Flange dimensions D 1 C 1 T 2 d a min. d b max. D a max. Mounting dimensions min. D b min. S a min. S b min. max. b max. Constant e Axial load coefficient Y 1 Y 0 (Refe.) Mass (kg) JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR [ Note ] 1) The beaing numbe of a tapeed olle beaing with a flanged oute ing contains the auxiliay symbol B. Example 30203JRB

129 4. Tapeed olle beaings 32200JR seies 32200JR 32200JRB S a S b 1 T C C 1 T 2 b ud B ud ud 1 ud a ud b ud a ud b Dynamic equivalent load P =XF +YF a F a F e a > e F F X Y X Y a Y 1 Static equivalent load P 0=0.5F +Y 0 F a Note that if P 0<F, it is assumed that P 0=F. Fo e, Y 1, and Y 0, use values given in the table. Bounday dimensions d D T B C 1 min. min. Beaing 1) No. Basic load atings (kn) C C 0 Limiting speeds (min 1 ) Gease Oil lub. lub. Load cente a Flange dimensions D 1 C 1 T 2 d a min. d b max. D a max. Mounting dimensions min. D b min. S a min. S b min. max. b max. Constant e Axial load coefficient Y 1 Y 0 (Refe.) Mass (kg) JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR JR [ Note ] 1) The beaing numbe of a tapeed olle beaing with a flanged oute ing contains the auxiliay symbol B. Example 32204JRB

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131 5. Suppot Beaings and Suppot Beaing Units fo Pecision Ball Scews Contents Page 5. 1 Stuctue and featues Composition of identification numbes Toleance of suppot beaings fo pecision ball scews Axial load and displacement 174 Beaing and beaing unit dimension tables SAC0000 and SAC00000 seies 176 BSU0000BDF(DFD, DFF) seies 178 BSU0000BDF(DFD, DFF) -T seies

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133 5. Suppot beaings and suppot beaing units fo pecision ball scews 5. 1 Stuctue and featues Suppot beaings fo pecision ball scews The SAC type suppot beaings ae angula contact thust ball beaings specifically fo suppoting the scew shafts of pecision ball scews (see Fig. 5. 1). The beaings suppoting the pecision ball scews coespond to the type with contact seal. Consult JTEKT fo details about the type with contact seal and the pai pattens. Both-side sealed type 60 These beaings have many, small-diamete balls and thick section innend oute ings. The contact angle of these beaings is 60 enabling a high axial load and a cetain degee of adial load to be applied simultaneously. 1) Featues of suppot beaings fo pecision ball scews Matching example of one-side sealed type Fig Stuctue of suppot beaings fo pecision ball scews High igidity Has highe igidity against axial load than conventional standad beaings (see Fig. 5. 2). Compact and lightweight Since this beaing eliminates the need fon additional adial beaing o thust beaing, it allows a compact suounding design, theeby contibuting to a eduction in the weight of the total system. High pecision A high-pecision beaing suitable fo pecision ball scews. Peload adjustments not equied Peload is peadjusted to ensue an adequate peload afte mounting. As a esult, complicated adjustments ae not equied duing mounting. Low toque Requies lowe fiction toque than the tapeed olle beaing o thust olle beaing. (μm) 40 Axial displacement Angula contact ball beaing (contact angle : 40 ) (u35 u72) Tapeed olle beaing (u35 u72) Thust boll beaing (u35 u62) Suppot beaing (u35 u72) Needle olle thust beaing (u35 u52) Axial load (kn) Fig Relationship between axial load and displacement (compaison between suppot beaings and othe beaings) *The axial displacements shown above ae values of the single-ow beaings not peloaded. 2) Matched pai o stack suppot beaings Combination of two Combination of thee Combination of fou Table 5. 1 Types and suffixes of suppot beaings Type and suffix of suppot beaing Suffix DB Suffix DFD Suffix DFF Suffix DF [ Remaks ] 1. A "V" mak is put on the outside sufaces of the oute ings of matched paind stack beaings to indicate thei combination type. Fo handling pecautions of the type G beaing, efe to the beaing dimension table "1. 2 Matched paingula contact ball beaings." 2. Type G beaings ae also manufactued, which enable any desied combinations. Fo desciptions of the type G beaing, efe to the beaing dimension table "1. 2 Matched paingula contact ball beaings." 171

134 5. Suppot beaings and suppot beaing units fo pecision ball scews Suppot beaing units fo pecision ball scews The suppot beaing unit fo pecision ball scews is a unit poduct combining the SAC type suppot beaing and a housing machined to a high pecision. Std. seies : BSU0000 T seies : BSU0000-T Fig Seies and stuctues of suppot beaing units fo pecision ball scews 1) Types of matched pai o stack beaing Table 5. 2 Types of matched pai o stack beaing Type and symbol Combination of thee beaings Combination of two beaings (Suffix : DF) (Suffix : DFD) 2) Featues of suppot beaing units fo pecision ball scews Simple mounting wok This is a unit poduct consisting of a beaing whee the peload is adjusted and an adequate quantity of gease is sealed within the beaing, and is mounted in a compact housing. Thus the suppot beaing unit can be easily mounted on a machine. Excellent dust-poof pefomance Having a high-pefomance built in oil seal the suppot beaing unit, with low toque opeation, is excellent in dust-poof pefomance. Capability of coping with any desied design In addition to the standad poducts listed in the dimension tables, JTEKT manufactues suppot beaing units to meet the suppot stuctues of vaious ball scews. Consult JTEKT fo moe infomation. Combination of fou beaings (Suffix : DFF) 172

135 5. 2 Composition of identification numbes (suppot beaings and suppot beaing units fo pecision ball scews) Suppot beaings fo pecision ball scews S A C B D B M G P 4 Z Suppot beaing fo pecision ball scews Nominal boe diamete 20 : 20 mm Nominal outside diamete 47 : 47 mm Intenal design code Toleance class symbol P4Z : JTEKT standads class 4 (Equivalent of JIS class 4) P5Z : JTEKT standads class 5 (Equivalent of JIS class 5) Cage symbol MG : molded cage made of polyamide esin Matched pai o stack symbol DB : back-to-back DF : face-to-face DFD : thee beaings making up face-to-face + tandem DFF : fou beaings making up face-to-face + tandem [Note] Amount of peload is standadized fo each matched pai type. Suppot beaing units fo pecision ball scews B S U B D F D -T Suppot beaing unit fo pecision ball scews Nominal boe diamete 30 : 30 mm Nominal outside diamete 62 : 62 mm Seies code no code : std. seies -T : T seies Matched pai o stack symbol DF : face-to-face DFD : thee beaings making up face-to-face + tandem DFF : fou beaings making up face-to-face + tandem Intenal design code 173

136 5. Suppot beaings and suppot beaing units fo pecision ball scews 5. 3 Toleance of suppot beaings fo pecision ball scews The suppot beaings fo pecision ball scews ae manufactued to specific JTEKT standads suitable fo the equiements of pecision ball scews (see Table 5. 3). Table 5. 3 Pemissible dimensional deviations and limits of suppot beaings fo pecision ball scews (1) Inne ing Nominal boe diamete d Single plane mean boe diamete deviation 3 dmp Single boe diamete deviation 3 ds Single inne ing width deviation 3 Bs Inne ing width vaiation V Bs Unit : μm Class 5Z Class 4Z Class 5Z Class 4Z Classes 5Z, 4Z Class 5Z Class 4Z Class 5Z Class 4Z Class 5Z Class 4Z Class 5Z Class 4Z ove up to uppe lowe uppe lowe uppe lowe uppe lowe uppe lowe max. max. max. max K ia Pependiculaity of inne ing face with espect to the boe S d K ia : Radial unout of assembled beaing inne ing S ia : Axial unout of assembled beaing inne ing S ia (2) Oute ing Nominal outside diamete D Single plane mean outside diamete deviation 3 Dmp Single outside diamete deviation 3 Ds Deviation of a single oute ing width 3 Cs Ring width vaiation V Cs Unit : μm Class 5Z Class 4Z Class 5Z Class 4Z Classes 5Z, 4Z Class 5Z Class 4Z Class 5Z Class 4Z Class 5Z Class 4Z Class 5Z Class 4Z ove up to uppe lowe uppe lowe uppe lowe uppe lowe uppe lowe max. max. max. max Same as Same as toleance 3 Bs, toleance S ia, d being that d being that of the same of the same beaing beaing. K ea : Radial unout of assembled beaing oute ing S D : Pependiculaity of oute ing suface with espect to the face S ea : Axial unout of assembled beaing oute ing K ea S D S ea 5. 4 Axial load and displacement (suppot beaings fo pecision ball scews) (μm) 25 SAC1747BDF,SAC2047BDF (μm) SAC2562BDF,SAC3062BDF 14 SAC2562BD SAC2562BD 15 SAC3572BDF,SAC4072BDF SAC4575BDF,SAC4090BDF SAC45100BDF,SAC50100BDF,SAC55120BDF 8 SAC2562BD SAC60120BDF Axial displacement Axial load (kn) (Matched pai, standad peload) Fig Relationship between axial load and displacement (suppot beaings fo pecision ball scews) Axial displacement Axial load (kn) (Compaison of numbe of beaing ows) 174

137 175

138 5. Suppot beaings and suppot beaing units fo pecision ball scews SAC0000, SAC00000 seies Contact angle 60 Two-beaing combination Thee-beaing combination Fou-beaing combination B 1 DB DBD DBB DBT 1 ud ud 1 ud 1 ud ud 2 ud 2 DF DFD DFF DFT DT DTD Bounday dimensions d D B 1 min. min. Basic dynamic 1) load atings (kn) C a Max. axial loads (kn) Single Double Tiple ow ow ow Limiting speeds (min 1 ) Gease Oil lub. lub. Beaing 2) No. Intespace volume (cm 3 /ow) Dimensions d 1 d 2 D 1 D 2 Standad peloads (kn) Two Thee Fou beaings beaings beaings Stating toques (mn m) Two Thee Fou beaings beaings beaings Axial sping constants (N/μm) Two Thee Fou beaings beaings beaings (Refe.) Mass (kg/ow) SAC1747B SAC2047B SAC2562B SAC3062B SAC3572B SAC4072B SAC4090B SAC4575B SAC45100B SAC50100B SAC55120B SAC60120B [ Notes ] 1) The value of the basic dynamic load ating of a single beaing is shown. Fo those of matched paind stack beaings, see table below. Dynamic equivalent load P a=xf +YF a Numbe of ows to eceive axial load Basic dynamic load ating Sample combination (aow indicates diection of load.) Single ow Double ow Tiple ow C a DB DF DBD DFD C a DT DBD DFD DFF C a 2.16 DTD DBT DFT 2) The identification of a matched beaing is composed of the beaing numbe of a single ow beaing followed by the suffix (DB, DF, etc.). Sample combination Numbe of ows to eceive axial load F a 2.17 F F a >2.17 F X Y X Y Two beaings DB DF Single ow DT Double ow Single ow Thee beaings DBD DFD Double ow DTD Tiple ow DBT DFT Single ow Fou beaings DBB DFF Double ow DBT DFT Tiple ow

139 5. Suppot beaings and suppot beaing units fo pecision ball scews BSU0000BDF(DFD, DFF) seies x x 2 L x 3 θ 1 Z 1 M 1 θ ud ud 1 ud 3 ud x 1 ud 1 ud 2 ud 1 up 1 up Z 2 M 2 L 3 L 2 L 1 Dimensions d D D 1 L L 1 L 2 L 3 d 1 d 2 x x 1 x 2 x 3 Applicable Unit Quantity Mounting hole of housing Tapped hole fo Dust-poof cove/dampe shaft dia. identification of d 3 P θ Z 1 M 1 P 1 θ 1 Z 2 M 2 numbe beaing No. of No. of ( ) ( ) ( ) ( ) holes theads holes theads Standad peload (kn) Stating toque (mn m) (Refe.) Mass (kg) BSU1747BDF M M BSU2047BDF M M BSU2562BDF M M BSU2562BDFD M M BSU3062BDF M M BSU3062BDFD M M BSU3572BDF M M BSU3572BDFD M M BSU3572BDFF M M BSU4072BDF M M BSU4072BDFD M M BSU4072BDFF M M

140 5. Suppot beaings and suppot beaing units fo pecision ball scews BSU0000BDF(DFD, DFF) - T seies x x 2 L x 3 θ 1 Z 1 M 1 θ ud ud 1 ud 3 ud ud 1 ud 2 ud 1 x 1 up up 1 Z 2 M 2 L 3 L 2 L 1 B Dimensions d D D 1 B L L 1 L 2 L 3 d 1 d 2 d 3 x x 1 x 2 x 3 Unit identification numbe Quantity of beaing Mounting hole of housing Tapped hole fo Dust-poof cove/dampe P θ Z 1 M 1 P 1 θ 1 Z 2 M 2 ( ) ( No. of ) ( ) ( No. of ) holes theads holes theads Standad peload (kn) Stating toque (mn m) (Refe.) Mass (kg) BSU1747BDF - T M M BSU2047BDF - T M M BSU2562BDF - T M M BSU2562BDFD - T M M BSU3062BDF - T M M BSU3062BDFD - T M M BSU3572BDF - T M M BSU3572BDFD - T M M BSU3572BDFF - T M M BSU4072BDF - T M M BSU4072BDFD - T M M BSU4072BDFF - T M M

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142 II. Oil / Ai Lubication System Contents Page 1. Oil / ai lubicato Ai cleaning unit

143 II. Oil / Ai Lubication System 1. Oil / ai lubicato 1. 1 Oil / ai lubication Oil / ai is a new method of lubication, which was developed to pevent atmospheic contamination caused by oil mist leakage, a phenomenon caused by the high speed of the spindles of machine tools combined with oil mist lubication. In oil / ai lubication, an extemely small quantity of oil is supplied and spayed by ai pessue diectly into the beaings. JTEKT has poduced an oil / ai lubicatond an ai cleaning unit, fo use as a lubication system. 1) Featues of oil / ai lubication q Ensues a low level of tempeatue incease and powe loss of beaing and enables a high otation speed. Supplies the necessay quantity of oil to each beaing in a eliable manne. w High eliability. Since new oil is constantly supplied to beaings, the use does not need to be concened about the sevice life of the lubication oil. Futhemoe, compessed ai, which inceases the intenal pessue of the spindle, is effective in peventing dust o cutting fluid fom enteing fom outside. e No atmospheic contamination. A small quantity of oil flows on the sufaces of piping walls contolled by compessed ai. This mechanism eliminates atmospheic contamination caused by oil mist leakage fom oil mist lubication. 2) System diagam of oil / ai lubication Ai inlet Lubicato main unit Pessue gauge Pessue switch (detects ai pessue) Ai 3) Example of connections of oil / ai lubication system Compesso AC 100V Mixing valve Oil / ai outlet pot Aftecoole KOYO ai cleaning unit Oil piping (u6 u4 tube) Ai piping (u8 u6 tube) 1-5m ecommended Lubication is also possible in this diection. Spindle Within 5m Ai pessue MPa KOYO oil / ai lubicato main unit F E Oil / ai piping (u4 u2.5 tubes) Oil / ai outlet pot (must be povided) Fig Example of connections of oil / ai lubication systems Solenoid valve (foi supply) Tank Contolle (time) Solenoid valve (fo pump opeation) Ai-diven pump Oil level switch Oil Mixing valve Quantity contol valve Check valve Oil / ai Pessue switch (detects oil pessue) 184 Fig System diagam of oil / ai lubication

144 1. 2 Oil / ai lubicato 1) Featues of KOYO oil / ai lubicato q Lubication (dischage) intevals can be set to desied values. The lubicatollows adjustment of lubication (dischage) intevals fom 1 to 99 minutes so that optimum settings fo lubication (dischage) intevals can be selected. A lock mechanism is povided. w A solenoid valve used to stop ai flow is fitted. It is included with the standad accessoies. The valve stops ai flow when the machine main unit stops. This eliminates the need fo valve opeation when shutting down the machine when not in use. e Oil can be dischaged continuously by manual opeation. Befoe stating oil / ai lubicato, the ai in the piping must be dischaged (ai bleed). The lubicato has a cicuit built in that allows a single o successive 11 ound oil dischage by manual opeation. A unique safety device is built in. A level switch is attached to the oil tank, and pessue switches ae attached to main oil and ai pipes. In the event of failue of the lubicato, the location of the failue is indicated by a lamp. In addition, an abnomality signal can be output fom the abnomality signal contact points (EMG NO- EMGCOM and EMG NC-EMGCOM teminals on the side of the contolle). KOYO oil / ai lubicato KOYO mixing valve Dischages a small quantity of oil at a fixed ate into the compessed ai flow fo oil / ai lubication. Contolle side view Contolle font view 185

145 II. Oil / Ai Lubication System 2) Model numbe of oil / ai lubicato (including mixing valve) Model numbe L A S 1 A 4 B - 1 KOYO oil / ai lubicato Mixing valve model numbe Table 1. 1 Symbols of mixing valves and oil dischage quantity Symbol of Oil dischage quantity mixing valve (ml/stoke) A 0.01 B 0.03 C 0.05 D 0.10 Fo the dischage intevals of the oil / ai, efe to Supplementay table 6 on page ) Outline dawing and specifications of oil / ai lubicato Oil dischage quantity symbol (see Table 1. 1) Numbe of dischage pots 1) 4 : fou B pots Oil dischage quantity symbol (see Table 1. 1) Numbe of dischage pots 1) 1 : one A pot 1) The standad numbe of oil dischage pots is 5. As it is changeable, specify accoding to need. The numbe of maximum available pots is 8 pe block. Lubication pot Ai inlet Dischage inteval contol time Powe connection Spae pot u21 Ai inlet RC F Ai supply pot RC Oil supply pot RC E Oil level indicato (u8 u6 tube) (u6 u4 tube) 4-u7 Ai pessue gauge Ai supply pot Oil supply pot Table 1. 2 Specifications Item Supply voltage Powe consumption Sevice ai pessue Specification AC100V, 50 / 60Hz With pump in opeation : appox. 20W Pump not in opeation : appox. 12W MPa Viscosity of oil used mm 2 /s Any desied value between Lubication 1 and 99 minutes in oneminute (dischage) intevals intevals Tank capacity 1.8L (effective oil quantity : 1.4L) Contact point a : (EMG NO) 250V AC, 5A Capacity of 30V DC, 5A abnomality signal Contact point b : contact points (EMG NC) 250V AC, 2A 30V DC, 3A Mass (efe.) 15 kg [ Note ] AC200V is also available. Consult JTEKT. 37 (Unit : mm) Fig Outline dawing and specifications of oil / ai lubicato 186

146 4) Outline dawing and specifications of mixing valve Oil plug Ai plug 20 8 Ai flow egulating needle valve L 35 Needle valve fixing nut 25.5 (22) 7 24 Making L2 L1 2-u6.5though holes 63.5 (16) A B B B B (31) (10) 9 Specifications The standad numbe of oil dischage pots is 5. As it is changeable, specify accoding to need (8 pots pe block at maximum). No. of pots L L L Dischage pot (fo u4 u2.5 tube) Pipe fitting Ai inlet (fo u8 u6 tube) (16) (min.26) Pipe fitting Oil inlet (fo u6 u4 tube) (Unit : mm) Fig Outline dawing of KOYO mixing valve (example of 1A4B-1) 187

147 II. Oil / Ai Lubication System 2. Ai cleaning unit Clean, dy ai is equied fo oil / ai lubication, pneumatic beaings, etc. JTEKT has developed and commecialized the ai cleaning unit KAU05, a compact unit consisting of filtes, an ai dye, mist sepaatos, and othe pats. This unit efficiently and effectively emoves moistue, oil, dust, etc. contained in compessed ai. 1) Featues of KOYO ai cleaning units q Removes moistue efficiently by efigeated ai dye. w Its mico-mist sepaato emoves oil content % and solid foeign matte 0.01μm o geate in paticle size. e Contains a diffeential pessue detection switch, which indicates clogging of filte. In addition, an output signal is obtained fom teminals attached on the diffeential pessue detection switch. (Font) (Rea) KOYO ai cleaning unit KAU05 2) Piping system diagam Main line filte Refigeated ai dye Mist sepaato Mico-mist sepaato Ai inlet Ai outlet Dain pot Pessue educing valve Diffeential pessue detection switch Fig Piping system diagam of ai cleaning unit 188

148 3) Outline dawing and specifications of ai cleaning unit Diffeential pessue detection switch Compessed ai outlet Rc3/8 Compessed ai inlet Rc3/8 Illuminated switch Evapoating tempeatue gauge Refigeated ai dye Main line filte Confimation window of dain Pessue gauge Pessue educing gauge 498 Mico-mist sepaato Mist sepaato 4-u u Dain pot Rc1/4 (Rea) Fig Outline dawing of KOYO ai cleaning unit Table 2. 1 Specifications of KOYO ai cleaning unit KAU05 Item Specification Teatment ai flow ate 0.52/0.57 m 3 /min Inlet ai pessue 0.7 MPa Maximum tempeatue of inlet ai 50 : Main line filte 3 to 50 μm (95%-aesting paticle size) Mist sepaato 0.3 μm (95%-aesting paticle size) Mico-mist sepaato 0.01 μm (95%-aesting paticle size) Oil content sepaation efficiency % Solid substance sepaation efficiency 100% if 0.01 μm o geate Supply voltage Single-phase 100 V AC (50/60 Hz)* Powe consumption 180/202 W (50/60 Hz) (at 100 V) Mass (efe.) 26 kg *AC 200V is also avilable. 189

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150 III. Handling of Beaings Contents Page 1. Handling and mounting of beaings

151 III. Handling of Beaings 1. Handling and mounting of beaings 1. 1 Handling pecautions of beaings Handling of beaings Since ball & olle beaings ae made to a highe pecision than geneal mechanical pats, they should be handled caefully Checking dimensions of peipheal pats of beaings Cleaning beaings Mounting beaings q w e t y Maintain beaings and thei suoundings in a clean condition. Handle with cae. A sevee shock to a beaing by ough handling may esult in damage such as flaws, nicks and chipping. Use coect handling tools. Execise cae fo ust pevention of beaings. Avoid handling and stoing them in a highly humid atmosphee. Beaing should be handled by an expeienced peson. Standad opeating pocedue fo handling beaings should be established. Stoage of beaings Cleaning of beaings and thei peipheal pats Inspection of dimensions and finish of peipheal pats of beaings Mounting Dismounting Inspection afte mounting Maintenance and inspection Replenishment of lubicant Checking beaings afte mounting Fig Mounting wokflow Checking dimensions of peipheal pats of beaings Befoe mounting the beaing, clean the shaft, housing, space, etc. Ensue that the inside of the housing is absolutely fee fom any esidual wapping mateial (SiC, Al 2O 3, etc.), molding sand, o chips. Next, inspect othe pats. Check that the dimensions, shapes and oughness ae as shown in the dawing, and thee is no flaw, bu o bab. Measue the beaing diametend the boe diamete of the housing at seveal positions as shown in Figs and 1. 3, and confim that the fitting is made coectly. Recod the measued values of these pats along with the inspection numbe of the beaing to be mounted Stoage of beaings Beaings ae shipped afte high-quality anticoosive oil is applied to them followed by a suitable wapping and packing. Thei quality is guaanteed as long as the wapping and packing ae not damaged. Beaing, if they ae to be stoed fo long time, should be stoed on a shelf at least 30cm fom the gound at 65% o less humidity at a tempeatue of aound 20:. Avoid diect exposue to sunlight. Keep beaings at a distance fom walls Mounting of beaings The mounting condition of the beaings affects the accuacy, pefomance and life of machines. To optimize the pefomance of the beaings, it is necessay to stictly follow the pocedue and instuctions to mount them. The pocedue fo mounting the beaings is shown in Fig In this section, a geneal pocedue fo mounting the beaings is descibed in accodance with the wokflow shown in Fig Fig Measuing positions of shaft diamete Fig Measuing positions of housing boe diamete Besides, pay attention to the fillet adii and the squaeness of the shouldes of the shaft and housing. (See Fig on page 193.) Fo the toleances fo the shaft diametes and the boe diametes of the housing, efe to Figs and 6. 3 of "6. Rigidity and peload of beaings". Also, fo the accuacy of the shaft and housing as well as the fillet adii, efe to "9. Designing peipheal pats of beaings". 192

152 Accuacy of shaft Angle diffeence fom the boe diamete of the beaing Ciculaity, cylindicity A Fitting with the boe diamete of the beaing Ciculaity B Accuacy of housing Flatness Flatness Squaeness Squaeness (in tems of shaft A - B) (in tems of shaft A - B) Flatness Squaeness (in tems of shaft A - B) A B Coaxiality (in tems of B) Flatness Squaeness (in tems of shaft A - B) Coaxiality (in tems of A) Flatness Squaeness (in tems of shaft A - B) Ciculaity, cylindicity Fitting with the extenal dimension of the beaing Ciculaity, cylindicity Fitting with the extenal dimension of the beaing Coaxiality (in tems of B) Coaxiality (in tems of A) Paallelism B Squaeness A (in tems of B) Flatness Paallelism (in tems of A) Retaining plate Space Locknut Pay special attention to the cicled pats in the figue to check that thee is no bu o bab. Fig Points fo checking the accuacy Cleaning beaings Afte pepaing the pats necessay fo mounting the beaings, unwap the beaings just befoe stating to mount them. Anticoosive oil is applied to the beaings to pevent coosion. Afte unwapping the beaings, clean them to emove the anticoosive oil following the pocedue shown in Fig Afte cleaning, degease and dy the beaings. Then, seal gease (in case of gease lubication) and mount the beaings. <Wokflow> Unwap the beaings Cleaning Rough cleaning Final cleaning Caution In geneal, white keosene is used to clean the beaings. Be caeful not to contact the impuities in the cleaning bath with the beaings due to aised bottom. Cay out the ough cleaning only to oughly emove the anticoosive oil. Refain fom cleaning the beaings by otating them. Always use the new cleaning oil to clean the beaings pefectly in the final cleaning. In the final cleaning, otate the beaings in the cleaning oil to emove the anticoosive oil fom the inside of the beaings. Degeasing (dying) Caution Afte the cleaning, handle the beaings in a clean envionment. When handling them, wea gloves to pevent ust due to sebum. Neve otate the beaings afte degeasing. Fig Cleaning wokflow 193

153 III. Handling of Beaings Mounting beaings The pepaation befoe mounting the beaings vaies depending on the beaing types and lubication as shown in Fig Fo details, see Fig to mount the beaings. In case of the angula contact ball beaings, the fitting mak is indicated on the outside suface of the beaing (see page 54). Mount the beaing in the coect diection efeing to the fitting mak. Beaing with tapeed boe No Yes Cleaance adjustment Refe to section (2). lubication, is vey susceptible to flaws, because it is cleaned and degeased and is in metallic contact with a olling element and aceway. To potect the aceway duing the mounting, it is ecommended to apply a small quantity of oil used fo the machine to be mounted inside the beaing. Shinkage fit Heat the beaing assembly o inne ing on an induction heate o hot plate to induce expansion befoe mounting it onto a shaft. If this method is used, no foce is applied to the beaing and opeation is caied out in a shot time. When a hot plate is used to heat up a beaing assembly, the use of a jig as shown in Fig enables efficient heating of the inne ing. Lubication Oil lubicant Gease lubicant Jig Fig Inne ing heating jig Gease sealing Refe to section (3). Mounting on the shaft and the housing Refe to section (1) (1) Mounting on shaft and housing q Fig Pepaation befoe mounting Beaing mounting Mounting method of the beaings diffes depending on types and fitting conditions. In case of the beaings fo machine tool spindles, the inne ing is usually otated. Theefoe, the intefeence fit is applied fo the inne ings, and the cleaance fit is applied fo the oute ings. As a method of intefeence fit, the shinkage fit is usually applied fo the cylindical boe beaings. In case of the beaings with tapeed boe, the inne ing is pess fitted in the tape shaft. In this case, the beaing intenal cleaance needs to be adjusted as descibed in section 1.2.3(2) befoehand, because it is necessay to contol the adial intenal cleaance afte fitting. The cleaance fit is used to fit the oute ing in the housing. To facilitate the mounting, the housing is heated to expand the boe diamete befoe mounting the beaing. The beaing befoe mounting, which is used fo oil Specify the heating tempeatue of the beaing in accodance with the size and the equied expansion, efeing to Fig Specify the tempeatue about 20 to 30: highe than the equied tempeatue, taking into consideation the tempeatue to be educed duing the opeation. Howeve, neve heat the beaing up to 120: o moe. Afte mounting the beaing, shinkage will occu in the width as the beaing cools off. Theefoe, fit the inne ing and the shoulde fimly using a locknut to pevent cleaance between them. Expansion of boe diamete [μm] Tempeatue diffeence 3 T 90; 80; 70; 60; Boe diamete d [mm] 50; 40; 30; 20; Fig Heating tempeatue and expansion of inne ings 194

154 Pess fit Be sue to use the specific jig to mount the inne ing to the shaft and the oute ing to the housing. When pess fitting the inne ing and the oute ing, hold only the inne ing and the oute ing, espectively, and apply gently unifom pessue to the whole cicumfeence suface. Neve mount the ings using hamme. To facilitate the mounting, it is ecommended to apply a small quantity of lubicant to the shaft o housing befoe pess fitting. [ Refeence ] Foce is necessay to pess fit o emove beaings The foce necessay to pess fit o emove inne ings of beaings diffes depending on the finish of shafts and how much intefeence the beaings allow. The standad values can be obtained by using the following equations. (In the case of solid shafts) d D i K a 9.8 ƒ k 3 deff B 10 3 (1. 1) (In the case of hollow shafts) d d 2 D i d 2 d D i K a 9.8 ƒ k 3 deff B 10 3 (1. 2) Fig Pess fitting by pessing machine Mounting fixtue Mounting fixtue (Inne ing pess fit) (Oute ing pess fit) (Inne ing pess fit) Whee: K a : foce necessay fo pess fit o emoval N 3 deff : effective intefeence mm ƒ k : esistance coefficient Coefficient taking into consideation fiction between shafts and inne ings... efe to the table below. B : nominal inne ing width mm d : nominal inne ing boe diamete mm D i : aveage outside diamete of inne ing mm d 0 : hollow shaft boe diamete mm Fig Example of pess fitting jig Value of esistance coefficient ƒ k Conditions Pess fitting beaings on to cylindical shafts Removing beaings fom cylindical shafts Pess fitting beaings on to tapeed shafts o tapeed sleeves Removing beaings fom tapeed shafts o tapeed sleeves Pess fitting tapeed sleeves between shafts and beaings Removing tapeed sleeves fom the space between shafts and beaings ƒ k

155 III. Handling of Beaings w 196 Tightening of beaings Tightening of inne ing As a way of fixing the inne ing to a shaft, a locknut is usually used. Fig shows an example of fixing an inne ing using a locknut. Locknut Cuving Pulling foce (lage) Pulling foce (small) Compession foce (lage) Fig Example of fixing on inne ing using a locknut As a cleaance is pesent between thead of the locknut and that of the shaft, fixing the inne ing by using a locknut esults in the cente of the locknut deviating fom the cente of the shaft. This deviation in tun causes inclination of the inne ing o bending of the shaft. As a esult, the unning accuacy of the shaft is deceased on abnomal tempeatue incease is expeienced due to the high load applied to the beaing (see Fig ). To settle this poblem, positioning (centeing) of the locknut is necessay afte tightening. [;] min 1 Gease lubication Tempeatue incease of oute ing DBD NN3010K Shaft adial unout [µm] Locknut Compession foce (small) Fig elationship between shaft adial unout and tempeatue incease of the oute ing caused by the faulty positioning of the inne ing Futhemoe, the axial foce geneated by tightening the locknut leads to compessive stain of the inne ing and inne ing space, which in the case of position peloading, influence the amount of peload applied to the beaing. Fo those applications which ae consideably affected by peload, such as a high-speed spindle, this compessive stain should be taken into consideation. Consideation to othe types of beaing suppots ae the inclination of inne ings, bending of shafts, and axial foces. In cases whee a intefeence fit sleeve is used to fix a beaing, the toleance of the sleeve is of vital impotance since positioning becomes difficult once the beaing is fitted. Tightening foces (shaft foces) of the locknuts o sleeves used to fix the inne ings ae indicated as standad values in the beaing dimension table. Note that if the intefeence of inne ing is lage and the numbe of beaing ows is lage, the pess fitting foce also becomes lage. Tightening of oute ings Oute ings ae fixed to the housing usually by means of a etaining plate. The etaining plate is fastened to the housing with seveal bolts. Inadvetent fastening of the etaining plate, howeve, may esult in an inclination and / o defomation of the oute ing. If inclination and / o defomation occus in the oute ing, the olling elements and the cage cannot otate popely, possibly causing unusual noise geneation. In ode to pevent this, it is necessay to tighten the etaining plate fastening bolts with an even toque in diagonal sequence. The fastening bolts should not be fastened individually to the final toque, but in a stepby-step sequence (see Fig ). 6 - M6 bolts Retaining plate Fastening sequence Intefeence: 30µm Housing Fasten bolts with each fastening toque in accodance with the sequence. 2-step fastening Fastening toque N m μm 5-step fastening Fastening toque N m μm Fig Raceway oundness vaiations with espect to the vaious fastening method A slight intefeence is povided between the housing and etaining plate to hold the oute ing fimly. If vaiations on the intefeence exist on the cicumfeence due to poo toleance of the etaining plate o housing, fastening the etaining plate may cause inclination of the oute ing. Theefoe, sufficient cae should be taken to ensue toleance of the etaining plate and housing. Fo the intefeence between the housing and etaining plate, efe to the dimension table fo each beaing.

156 (2) Adjusting of cleaance In case of the cylindical olle beaing with tapeed boe, it is necessay to adjust the dimension of the space to adjust the adial cleaance of the beaing. The adjustment is made as follows. (1) Lightly apply low-viscosity oil (keosene, etc.) to the tape pat of the shaft and fit slightly the inne ing of the cylindical olle beaing into the shaft (Fig ). Fig Tempoay mounting of inne ing (2) Using a block gauge, measue the distance between the end face of the inne ing and that of the shoulde (Fig ). Block gauge Fig Width of space (3) Tempoaily adjust the width of the space. Adjust the width of the space to the distance between the end face of the inne ing and that of the shouldes measued in step (2). It is ecommendable to make the outside diamete of the space lage than the diamete of the shaft shoulde to facilitate the pulling-out (Useful when pulling out the inne ing). Note: The paallelism of lateal side of the space must be 0.001mm o less. (4) Afte degeasing the outside suface and the boe, fit the tempoaily adjusted spacend mount the inne ing onto the shaft. Be caeful not to make cleaance between the end face of the spacend that of the inne ing and cleaance between the end face of the spacend that of the shaft shoulde (Fig ). (5) Place the dial gauge on the outside suface of the oute ing, and move the oute ing upwad and downwad on the axial line of the dial gauge needle to measue the esidual adial intenal cleaance (Fig ). (6) Afte measuement, pull the beaing and the space out of the shaft. Neve hit the beaing to pull it out (Hit gently the end face of the space of lage outside diamete). (7) Based on the adial intenal cleaance measued in step (5), use the equation shown below to calculate the adjustment value of the inne ing to obtain the desied esidual adial intenal cleaance. In case of tape 1/12, Adjustment value 3 A= (R sa R sb R sc) 12/K Whee: R sa: measued adial intenal cleaance... the value measued in step (5) R sb: desied adial intenal cleaance R sc: contaction of the oute ing aceway due to fitting (0 in case of cleaance fit) K : expansion coefficient of the inne ing aceway due to pess fitting Fomula to calculate R sc R sc = 3 Deff Fomula to calculate K K = d D i D e D 2 d ( 1 0 d ) 2 2 d ( D i ) D ( D h ) 2 D ( 1 e 2 D h ) Whee: 3 Deff : effective intefeence of oute ing D h : outside diamete of housing D e : oute ing aceway contact diamete ball beaing D e 0.2 4D d olle beaing D e D d D : nominal oute ing outside diamete d : nominal inne ing boe diamete (shaft diamete) d 0 : boe diamete of hollow shaft D i : inne ing aceway contact diamete ball beaing D i 0.2 D 4d olle beaing D i 0.25 D 3d Dial gauge Space Fig Mounting of space Fig Measuement of esidual adial cleaance 197

157 III. Handling of Beaings (8) Adjust the width of the space. The width of the space must be the value tempoaily adjusted minus the adjustment value calculated in step (7). Note: The paallelism of lateal side of the space must be 0.001mm o less. (9) Afte cleaning, mount the beaing and the space onto the shaft. Push inne ing sufficiently so that the end face of the spacend that of the inne ing as well as the end face of the spacend that of the shaft shoulde contact each othe completely (Fig ). (10) As in step (5), check the esidual adial intenal cleaance of the beaing. If the desied value of the adial intenal cleaance is not obtained, etun to step (7) and make adjustment again. (11) Afte checking that the desied value of the adial intenal cleaance in obtained in step (10), pull the beaing and space out of the shaft tempoaily to clean and degease them. In case of gease lubication, seal them with the specified amount of gease, and then eassemble them (3) Gease sealing If the sealed amount of gease o the sealing method is not appopiate, oveheating o instability (Fig ) may esult duing beaking-in, and an extended time of beaking-in may become necessay. Theefoe, be sue to seal the beaing with an appopiate amount of gease in coect manne. Sealing method of gease is descibed below. [;] 40 Peak tempeatue Fig Mounting of beaing Tempeatue Rotational speed incease Peak tempeatue Time Sample beaing 7014C 5DB Gease poduct name ISOFLEX NBU Sealed amount of gease [%] min min 1 Fig Relationship between sealed amount of gease and peak tempeatue q Pepaation befoe sealing Clean and degease the beaing. And check that thee is no stain of anticoosive oil o impuity on the intespace and oute sufaces of the beaing. An appopiate amount of gease must be applied unifomly to the specified locations in the beaing. To apply gease, it is ecommended to use a specific tool with measuing gauge, which has a nozzle tip. The tool used to apply gease also has to be cleaned off and degeased. Befoe applying gease, check the amount of gease to be sealed. The amount should be 10 to 15% of the space capacity of the beaing. (The space capacity of each beaing and the sealed amount of gease ae shown in the beaing dimension table.) w Method fo gease sealing Gease must be applied unifomly to the beaing aceway suface and the etaine guide as shown in Fig Aftepplying gease, manually otate the beaing to let the gease spead all ove the inside of the beaing. Also, aftepplication of gease, be caeful not to let impuities dust to the beaing. Angula contact ball beaing Geasing the oute ing aceway Inne ing Geasing the etaine boe Cylindical olle beaing Remove the oute ing, and apply gease to the mating suface of the etaine Apply gease between the etaine boe and the inne ing aceway Ball Retaine Unifomly apply gease to the contact point of the oute ing aceway and the balls fom between the outside of the etainend the oute ing boe Oute ing Remove the oute ing, and apply gease to the suface of the oute ing boe (aceway) Oute ing Rolle Inne ing Fig Gease sealing points Apply gease between the etaine boe and the outside of the inne ing Retaine

158 Check afte mounting beaings (1) Checking of peload Peload of the beaing affects its igidity and heat geneation. If the peload is inadequate, not only the standad pefomance is not obtained, but also the life span is shotened and seizue esults. Theefoe, it is impotant to check that the specified peload is applied to the beaing afte completing the mounting of the beaing. In this section, the following methods fo checking the peload, which ae geneally used, ae descibed (2) Beaking-in In case of the beaings fo gease lubication, afte installation of a beaing, poblems ae likely to occu due to apid tempeatue ise caused by the immediate application of the maximum specified otational speed. Theefoe, beaking-in of the beaing is ecommended, in which otational speed is inceased gadually. Specifically, olle beaings equie adequate beaking-in. Fig shows an example of beaking-in. ACT014DB NN3014K NN3012K q Check using the stating toque If the peload of the beaing becomes lage, the stating toque also tends to inceases. Theefoe, the peload can be checked by measuing the stating toque value. Wind the thead on the shaft o the oute ing and fix it. By pulling the thead tangentially, measue the tension of the thead when the beaing stats to otate using a tension gauge, etc. Afte obtaining the stating toque, the peload can be pesumed efeing to the coelation between the stating toque and the peload. The stating toque can be measued easily. Howeve, in case of the beaings used with low peload (e.g. angula contact ball beaing used as a spindle), the measuement eo can be lage because the stating toque is small. This method is ecommendable when using the ball scew suppot beaings by applying heavy peload to them. Note that it is necessay to standadize the sampling and measuement conditions because the condition of the lubicant and pulling speed affect the measuement esult. w Check using the axial igidity The peload is confimed efeing to the coelation between the shaft end axial deviation measued by applying the axial load to the shaft end, and the axial igidity and the peload. This method is not ecommendable when using a main shaft of high igidity because the deviation is vey small. To use this method, a lage-sized facility such as a load applying device is necessay. Also, it is necessay to standadize the sampling and measuement conditions because the pats othe than the beaing have elastic defomability. e Check using the pope vibations The peload is confimed efeing to the coelation between the sping constant of the beaing and the peload. This method guaantees accuacy and epeatability of measued values. Howeve, the fixing method has to be meticulously inspected and standadized because the esults ae affected by the fixing method. Rotational speed min Time h If caying out the beak-in, afte inceasing the otational speed, wait until the tempeatue of the beaing stops to incease o stats to decease. Then, incease the otational speed futhe. Neve incease the otational speed when the tempeatue of the beaing is inceasing. The highe the tempeatue of the beaing becomes, the faste the gease deteioates. Theefoe, it is impotant to monito the tempeatue duing the beaking-in. When the tempeatue eaches a cetain level, stop the opeation tempoaily. Afte the beaing cools off, esume the beak-in stating fom the otational speed at which the opeation was stopped o lowe. If the tempeatue is measued on the outside suface of the housing o etaining plate, the tempeatue at which the opeation should be stopped is the oom tempeatue plus 30 to 40: (Supposing that the oom tempeatue is 15 to 25:). The beak-in is not equied fo the beaings lubicated with oil. Howeve, if the beaings ae used fo the fist time ofte stoed fon extended peiod of time, it is ecommended to cay out the beak-in because an abupt incease of tempeatue may be expected due to the oil emaining in the lubication duct and the inside of the beaing (excessive oil quantity). Fig Example of beaking-in (In case of min 1 max. speed) 199

159 III. Handling of Beaings (3) Tial un and inspection A tial un and inspection ae caied out when beaings have been mounted, in ode to check whethe the mounting is adequate. In the case of a small spindle, the otation condition is examined initially by otating it manually. Afte confiming that the below conditions do not exist, a futhe inspection is caied out by a poweed un. Unsmoothness...Possible causes ae mixing of foeign matte, flaw in olling sufaces, etc. Gease used in gease lubication may cause a phenomenon of unsmoothness at the initial stage. In such cases, unsmoothness disappeas afte beaking-in. In the case of a lage spindle that cannot be otated manually, stat it unde unloaded condition and immediately afte stating, tun the powe off and allow to coast. Afte veifying that the shaft is fee of abnomal vibation o noise and otates smoothly, poceed to poweed un. Poweed un should be stated with no load applied and at a low speed, befoe being inceased gadually to a given condition. Noise, tempeatue incease, and vibation ae pincipal judging factos in poweed un and inspection. If a faulty condition such as shown in Tables 1. 1 and 1. 2 (page 200 and 201) occus, conduct a futhe inspection immediately. In some cases, it is necessay to emove the beaing fo inspection. Excessive toque...possible causes ae fiction in (heavy) the sealing device, insufficient cleaance, etc. Uneven otational...possible causes ae difective toque mounting, and / o eos in mounting dimensions. Table 1. 1 Beaing noises, causes, and countemeasues Noise types Causes Countemeasues Cyclic Not cyclic Othes Flaw noise simila to noise when punching a ivet 1) Binelling noise (unclea sien-line noise 1) ) simila to a lage Flaking noise hammeing noise Dit noise (an iegula sandy noise 1) ) Flaw noise, flaking noise often head in cylindical olle beaing with gease lubication, espe- cially in winte ot low tempeatue Squeak noise Abnomally lage metallic sound Flaw on aceway Binelling on aceway 1) Flaking on aceway Replace beaing. Insetion of foeign matte Flaws and flaking on olling elements Impove mounting pocedue, cleaning method and ust peventive method. Replace beaing. Replace beaing. If noise is caused by impope lubication, a pope lubicant should be selected. In geneal, howeve, seious damage will not be caused by an impope lubicant if used continuously. Abnomal load Incoect mounting Insufficient amount of o impope lubicant Impove cleaning method, sealing device. Use clean lubicant. Replace beaing. Review fitting, cleaance. Adjust peload. Impove accuacy in pocessing and mounting shafts and housings. Impove sealing device. Refill lubicant. Select pope lubicant. [ Note ] 1) In case of slow o medium otation. 200

160 Table 1. 2 Causes and countemeasues fo abnomal tempeatue ise Causes Too much lubicant Insufficient lubicant Impope lubicant Abnomal load Impope mounting excessive fiction Countemeasues Reduce lubicant amount Refill lubicant Select pope lubicant Review fitting and cleaance conditions and adjust peload Impove accuacy in pocessing and mounting shaft and housing. Review fitting. Impove sealing device Dismounting of beaings Dismounting a beaing fo euse o identification of causes of failue should be caied out in a caeful manne simila to that of when mounted. Cae should be taken to avoid damage to the beaing and othe pats. Specifically, when dismounting a beaing involving an intefeence, the dismounting pocess of the beaing should be taken into consideation at the designing stage of the shaft and housing. It is ecommended to make a jig fo dismounting whee appopiate. Nomally, listening ods ae employed fo beaing noise inspections. The device, which detects abnomalities though sound vibation, and the system, which utilizes acoustic emission fobnomality detection, ae useful fo moe pecise inspection. In geneal, beaing tempeatue can be estimated fom housing tempeatue, but the most accuate method is to measue the tempeatue of oute ings diectly via lubication holes. Nomally, beaing tempeatue begins to ise gadually when opeation is just stating; and, unless the beaing has some abnomality, the tempeatue stabilizes within one o two hous. Theefoe, a apid ise in tempeatue o unusually high tempeatue indicates some abnomality. 201

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162 IV. Examples of Beaing Failues Contents Page 1. Beaing failues, causes and countemeasues

163 IV. Examples of Beaing Failues 1. Beaing failues, causes and countemeasues It is necessay to cay out the maintenance and inspection to use the machine equipment always in stable conditions. The beaing is an impotant pat of the machine installation. If the beaing is damaged, the machine may become nonopeating and othe inadvetent effects may occu. Rotation noise, vibations, tempeatue and toque ae impotant phenomena to detemine the status of the beaing. If any abnomality is peceived in such phenomena, it is necessay to immediately find the cause of the poblem and take appopiate measues. In Table 1. 1, beaing failues, possible causes and countemeasues ae shown. Table 1. 1 Beaing failues, causes and countemeasues Tempeatue ise Noise Phenomena Excessive Instable Metallic noise Continuous noise Intemittent noise Vibations Causes Countemeasues Notes Excessively small quantity of Check the quantity of the enclosed Usually this phenomenon is accompanied by metallic lubicant gease and the oil / ai blow. noise. Gease may be deteioated o leaking if this Check that thee is no leakage in phenomenon occus duing nomal opeation in case of the oil / ai pipe. gease lubication. Excessively lage quantity of Check the quantity of the enclosed In case of gease lubication, the beaking-in may be lubicant gease and the oil / ai blow. insufficient. Angula contact ball beaing: Check the beaing axial Refe to case q (page 205). excessive peload cleaance and mounting Cylindical olle beaing: conditions. excessive negative cleaance Inadequate mounting pecision Check that thee is no If einstalling the beaing, it is necessay to check the misalignment. pecision of the pats afte dismounting it. Insufficient cooling Check the availability of the cooling capacity equied. Extenal factos Check that the belt tension is not excessive, the built-in moto is not heated excessively, and the coupling coe is pecisely placed. Deteioation of beaing Replace the beaing. Usually this phenomenon is accompanied by toque ise. Oil / ai lubication: bad exhaust Check the oil / ai exhaust oute. In case of oil / ai lubication, if the oil blows Gease lubication: insufficient intemittently (iegulaly) fom the exhaust pot, the beaking-in exhaust (oil dainage) is not caied out coectly. Excessively small quantity of lubicant Contact and intefeence between all otating pats and all non-otating pats Unbalanced shaft and impecise otation Rough suface and binelling of aceway Noise of cages, and slippage because of peload leakage Unbalanced shaft Check the quantity of the enclosed gease and the oil / ai blow. Check that thee is no leakage in the oil / ai pipe. Check the conditions of the mounted pats, including the labyinth. Adjust the shaft balance. Readjust the otational accuacy. Replace the beaing in the case of enty of foeign paticle, flaking and excessive load. If the peload is excessively small, check the axial cleaance and mounting conditions of the beaing. Adjust the shaft balance. Readjust the otational accuacy. This phenomenon is accompanied by excessive tempeatue ise. Gease may be deteioated o leaking if this phenomenon occus duing nomal opeation in case of gease lubication. If this phenomenon occus duing nomal opeation, it may be the seconday phenomenon of a tempoal failue. This phenomenon is accompanied by buzzing noise. If this phenomenon occus duing nomal opeation, it may be the seconday phenomenon of a tempoal failue. Refe to cases w and e (page 205 and 206). If thee is no measue taken, this phenomenon may occu epeatedly. 204 Excessive adial cleaance of cylindical olle beaing Rough suface and binelling of aceway Check the adial cleaance of the beaing. Check the mounting conditions. Replace the beaing in the case of enty of foeign paticle, flaking and excessive load. In case of the beaing with tapeed boe, the shaft nut may be loose. Also, the wea may have wosened. Refe to cases w and e (page 205 and 206).

164 Case q Excessive beaing peload Case w Enty of foeign paticle Causes 1) Inadequate fitting Excessively lage intefeence fitting of the inne ing Due to the incease of intefeence of the inne ing and the shaft, the diamete of the aceway expands and the peload inceases. Excessively small cleaance fitting of the oute ing If a tempeatue diffeence is geneated between the oute ing and the housing, the oute ing is compessed and the diamete of the aceway shinks, esulting in an incease in peload. 2) Inadequate tightening foce of the beaing If the tightening foce of the inne ing (nut shaft foce etc.) is excessively lage, the inne ing is defomed in axial diection and the peload inceases. 3) Excessive cooling of the housing If the oute suface of the housing is excessively cooled, the phenomenon descibed in item 1) is geneated and the peload inceases. 4) Failue in constant-pessue peloading and vaiable peloading system If the oute ing cannot be moved smoothly by the constant-pessue peloading and the peload vaiable spindle, the same phenomenon as in the case of the position peloading is geneated, and an excessive peload is applied to the beaing. Majo foeign paticles ae as follows. Coolant Chippings Ion chips (housing mateial) Causes 1) Poo sealing pefomance If the labyinth is not adequately configued fo use conditions, the sufficient sealing effect is not obtained, and the foeign paticles, including coolant, may be tapped in the beaing. 2) Pat not cleaned sufficiently If the pats ae not cleaned sufficiently, small bus and babs exist, they may fall into the inside of the beaing duing the opeation. 3) Dity lubicant If the oil lubicant is not completely washed out of the pipe, o if the envionment fo the enclosing gease is not adequate, foeign paticles may be tapped in the lubicant and the beaing may be damaged. Position peloading Intefeence (cleaance) of the oute ing Cooling of the housing Incease in the tempeatue diffeence Decease in the intefeence (cleaance) d0 Opeating d The oute ing is compessed if changed fom the cleaance fit to the intefeence fit. d0<d Heat expansion, and centifugal expansion Inadequate fitting, and excessive cooling d is futhe inceased. Fig Cause of incease in peload Fig Example of biting flaws fomed in aceway because of enty of foeign paticle 205

165 IV. Examples of Beaing Failues Case e Damage on the aceway suface (nick and flaking) Causes 1) Nick Nick may be poduced on the aceway suface if the main shaft is hit, any excessive load is applied to the beaing because of the clamping and unclamping of the tool, o the beaing is not popely handled. Nicks nea the shoulde (ball pitch) Fig Example of nicks 2) Flaking As the beaing becomes old, the flaking occus if the load is applied epeatedly to the aceway suface. Howeve, even in case of a new beaing, the flaking may occu if an excessive load is applied to the beaing o the oil film is fomed insufficiently. Also, the flaking may be geneated by the binelling (nicks). Fig Example of flaking 206