Who are ROLLVIS? medical electrical cylinders m easuring machines and laser machines robotics, chemicals, a nd all other fi elds of high technology

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2 Who are ROLLVIS? After its founding in 1970, ROLLVIS SA soon began to focus on the manufacture and marketing of satellite roller screws under the trademark «Rollvis swiss». Now a benchmark in this highly specialised fi eld, ROLLVIS SA has invested in the most powerful machines for the production of screws with low tolerance margins designed to individual specifi cations. A fast-growing company with a young and highly qualifi ed workforce, ROLLVIS SA recently moved into new ultra-modern premises near to Geneva. It is structured to preserve its human scale and its capacity to listen and adapt perfectly to its customers requirements. Four decades and more of skills and experience combined with the latest high-end techniques ensure its products comply with the most stringent and demanding standards, notably in the following applications: aeronautics, space defence, car industry moulding, injection (plastics and metal) optics, graphics special machine tools medical electrical cylinders m easuring machines and laser machines robotics, chemicals, a nd all other fi elds of high technology To ensure its satellite roller screws always gain by the latest progress in technology to make them ever more reliable, ROLLVIS SA has set up its own «Research and Development» department where its highly qualifi ed engineers and technicians use the most recent and most powerful design software available in their unceasing quest for the control of avant-garde technologies. New processes are constantly reviewed to optimise the product, production system, quality control, tests and trials for individual requirements. Even the most exacting customers swear by the outstanding reliability and quality of ROLLVIS products. Present on all the continents, over time ROLLVIS SA has built up an excellent sales network, so that wherever you are in the world, there are experts to give you answers and advice.

3 contents Introduction Satellite roller screws compared to ball screws Types of roller screws 3 and 4 Identifi cation system 5 Accuracy / Effi ciency 6 Geometry 7 Preloading 8 Preloading examples 9 2 Mean speed and axial load 10 Nominal lifespan 11 Rigidity 12 Rotation speed 13 Driving torque 14 and 15 Calculation example 16 and 17 Lubrication 18 and 19 Handling advice 20 Preference program Type RV diameters of 3.5 to Type RV diameters of 15 to Type RV diameters of 25 to Type RV diameters of 39 to Type RV diameters of 51 to Type RV diameters of 80 to Type BRV diameters of 8 to Type RVR diameters of 8 to Applications 30 à 32 No liability can be accepted for any errors or omissions. i We reserve the right to make changes in the interest of technical progress

4 Introduction ROLLVIS satellite roller screws are used to transform rotary movements into linear movements and vice versa. The bearing elements are threaded rollers between the screw and the nut. The high number of points of contact enables satellite roller screws to support very heavy loads. The ROLLVIS manufacturing programme comprises satellite roller screws without roller recycling (types RV and BRV) and with roller recycling (type RVR), in a range of accuracy classes. The ROLLVIS range also includes other types such as the reverse roller screw (type RVI) and the differential screw (type RVD). Satellite roller screws compared to ball screws The satellite roller screw is similar to the ball screw with the difference that the load transfer elements are threaded rollers. The main advantage of satellite roller screws is that they have a high number of points of contact to support the load. Load capacity and lifespan The main advantage of roller screws compared to ball screws is that their admissible static and dynamic load capacities are higher. The bearing function is ensured by threaded rollers instead of balls and the load is spread over a higher number of points of contact. Satellite roller screws like ball screws use Hertz s law. The admissible Hertz pressure is the same for satellite roller screws and ball screws. Satellite roller screws thus have a static load 3 times greater than that of ball screws and their lifespan is 15 times longer. Speed & acceleration Satellite roller screws can rotate much faster and support much greater acceleration. RV and BRV satellite roller screws are designed so that the rollers are not recycled. This means the mechanism can support twice the rotation speed of a ball screw. Acceleration can reach up to 3g. Lead & pitch Planetary roller screw can be achieved with smaller leads compared to ball screws. As the lead is a function of the pitch of the planetary roller screw, the lead can be very small (0.5mm and even less). Planetary roller screws can be achieved with entire or real numbers (i.e. lead of 3.32mm per revolution), which avoid reduction gears. This is an advantage compared to ball screws. The lead can be chosen and realised without any geometrical changes of both the screw shaft and the nut body, which allows updates with minor changes. In a ball screw the lead is limited by the dimension (OD) of the bearing ball, which is a standard feature. Rigidity & strength The many points of contact give a satellite roller screw greater rigidity and shock tolerance than a ball screw

5 Types of roller screws RV and BRV screws The main elements of RV and BRV satellite roller screws are the screw, the nut and satellite rollers. The screw has a multiple-start thread. The angle between the fl anks is 90 and the profi le is triangular. The nut has an internal thread identical to that of the screw. The rollers have a single-start thread with an angle the same as that of the nut. This ensures there is no axial movement between the nut and the rollers. The rollers do not therefore need to be recycled. The fl anks of the roller thread are convex. At each end of the rollers there is a cylindrical pivot and gear teeth. The pivots are mounted in the holes of the end rings, thus ensuring the rollers are equidistant. The end rings are fl oated in the nut body and axially secured with circlips. The gear teeth engage in gear wheels fi xed in the nut. This guides the rollers parallel to the axis to ensure perfect functioning. RV et BRV RVR screws RVR satellite roller screws have very fi ne threads and are used when very great positioning accuracy is required along with high rigidity and load-carrying capacity. The main elements of RVR satellite roller screws are the screw, the nut and the rollers which are guided and maintained at the correct distance in a cage. The screw has a single- or two-start thread with a triangular profi le. The angle between the fl anks is 90. The nut has the same internal thread as the screw. The rollers are not threaded but have grooves perpendicular to the screw axis. The distance between the grooves matches the exposed thread of the screw and nut. The fl anks are convex and the angle between them is 90. When the screw or nut rotates, the rollers are axially displaced in the nut. After a complete revolution, each roller is returned to its initial position by two cams at the end of each nut. They can be recycled this way because there is a groove the length of the nut. RVR The cage pockets are slightly longer than the rollers to enable them to move axially within the nut

6 Types of roller screws ( ctd.) RVI screws RVI satellite roller screws work on the same principle as RV and BRV screws except that their nut system is reversed. This means the rollers themselves rotate around the screw (instead of the nut in RV and BRV screws) and move axially within the nut. Apart from the screw threading where the rollers orbit, the journal is smooth and can have a special shape (e.g.: antirotation). The nut is threaded along its entire length and is much longer than on RV and BRV screws. It governs the overall travel of the complete screw and therefore limits it if needed. RVI RVD screws The RVD differential screw is actually a variant of the RV and BRV screws. Its components, expertly calculated and adjusted, are used to produce extremely fi ne threads (less than 0.02 mm). The movement of the rollers in this somewhat complex mechanism does however prevent a wide range of travel. The nuts are larger than on the RV and BRV types

7 Identifi cation system ExampleRV2 1 0 /30.5.R Design RV = ground thread, non-recycling rollers BRV = rolled thread, non-recycling rollers RVR = ground thread, recycling rollers RVI = ground thread reverse system RVD = ground thread differential screw Nut types 1 = single nut 2 = split nut 3 = double nut Nut design 1 = cylindrical nut 6 = nut with fl ange at one end 7 = nut with central fl ange 8 = special nut design Seal 0 = without wipers 1 = with wipers Screw diameter d 0 in mm Nominal lead P in mm Thread direction R = right B = right/left L = left Thread accuracyg1 = 6 µm/300 mm G3 = 12 µm/300 mm G5 = 23 µm/300 mm G9 = 200 µm/1000 mm (BRV only) 6-digit number to identify customer s specification - 5 -

8 Accuracy Satellite roller screws are divided into tolerance classes based on DIN 69051, part 3 (ball screws). The determining factor is the lead error V 300p referred to a thread length of 300 mm. The table opposite shows the tolerance classes: Tolerance Cl V 300p G1 6 µm/300 mm G3 12 µm/300 mm G5 23 µm/300 mm G9 200 µm/1000 mm Positioning satellite roller screws are supplied in tolerance classes G1, G3 and G5 and transport satellite roller screws (type BRV) in tolerance class G9. Lead accuracy symbols according to DIN 69051/3 P e 0 V 300p e p V up V 2πp L u nominal lead difference between required lead and nominal lead difference between actual and nominal lead over 300 mm difference between actual and nominal lead over a length L u travel variation over a length L u travel variation over one revolution effective travel Lead error The lead error e p relative to effective travel L u is calculated for the transport satellite roller screw by the following formula: Lead errors e p for positioning satellite roller screws are shown in the table opposite. For tolerance classes G1 and G3, the lead and torque diagrams are supplied with the screws. Lead is checked by a 3D measuring machine or on a measuring bench equipped with a laser interferometer. L E p in microns u for tolerance class up to morethan G1 G3 G5 315 mm mm 400 mm mm 500 mm mm 630 mm mm 800 mm mm 1000 mm mm 1250 mm mm 1600 mm mm 2000 mm mm 2500 mm mm 3150 mm 93 Effi ciency η 1 η2 Satellite roller screw Rollvis satellite roller screws achieve high rates of mechanical effi ciency. The figure opposite shows effi ciency rates η 1 for the ascent and η 2 for the descent, according to the helix angle. The effi ciency of a trapezoidal thread screw is shown for comparison. Satellite roller screws, unlike friction screws, are not self-locking. 60 Efficiency in % Trapezoidal thread screw Advantages High axial load capacity Long lifespan High effi ciency No backlash Extremely high rigidity Accuracy greater than 6 µm/300 mm High rotation speed (RV and BRV systems) Small leads (from 0.25 mm) with wide diameters (system RVR) Fast acceleration and deceleration Helix angle ϕ in deg. Applications Rollvis satellite roller screws have proved their superior worth in many fi elds of applications such as: Machine tools Measuring machines Specifi c machines (benders) Robotics Aeronautics (aeroplanes and helicopters) Space (rockets and satellites) Defence (tanks, cannons, missiles, etc.) Oil industry Nuclear industry Medical Chemical industry Optical Telescopes Graphics Laser machines Injection moulding machines Car industry - 6 -

9 Geometry Nut geometry and shape Standard satellite roller screws are available with 3 nut designs: single nut (ES) split nut (EF) double nut (ED) Single nuts have low axial backlash of 0.01 to 0.03 mm. The split cylindrical nut is preloaded by clamping the two halves of the nut in a housing. A precision spacer ring is mounted between the two halves to maintain the required level of preloading. Split nuts with a fl ange at one end have a spacer ring designed to hold the halves apart. The halves are aligned by a parallel key. Double nuts are preloaded in the same way as split nuts. SINGLE NUTS: Nuts in one piece with axial backlash Wipers (if requested by the customer) SPLIT NUTS: Nuts in two pieces, preloaded, without backlash Same dimensions as single nuts Reduced load capacities Wipers (if requested by the customer) DOUBLE NUTS: Two single nuts, preloaded, without backlash Same load capacities as single nuts About twice as long as single nuts Wipers (if requested by the customer) FLANGE SHAPES Shape A Shape B

10 Preloading F V F 1 F 2 Preloaded nuts are used to eliminate backlash and increase rigidity. Preloading should be carefully calculated to achieve the highest rate of effi ciency and the longest possible lifespan (see figure above). For preloaded nuts, in addition to the individual loads F 1 F n, preload F v must also be taken into account to determine the mean load F m. This yields new individual loads F 1v F nv. If for example an absence of backlash is required for all operational loads, preload F v must be selected according to the maximum load F max. Resulting load depending on preload F v An axial load on a preloaded nut system increases the load of one of the halves and relieves the other from the preloading force. The resulting load can be estimated by the following equations: Loaded half of nut: F nv(1) = F v + 0,65. F n [N] if F n < 2,83. F v [N] F nv(1) = F n [N] if F n 2,83. F v [N] Relieved half of nut: F nv(2) = F v - 0,35. F n [N] if F n < 2,83. F v [N] F nv(2) = 0 [N] if F n 2,83. F v [N] If a satellite roller screw only needs to be backlash-free for a specifi c load, preload F v should be selected according to the corresponding load F n. Unless the customer otherwise requests, split and double nuts are preloaded in the standard version to a maximum of 5% of the dynamic load capacity. F 1 F n [N] : individual loads F v [N] : preloading force F nv [N] : load resulting from the individual load and preloading F ma [N] : mean load taking into account preloading - 8 -

11 Preloading examples Preloading with rigid spacer (thickness calibrated by Rollvis SA) Flange nut Cylindrical nut Preloading with elastic washers Elastic washers Flange nut Cylindrical nut - 9 -

12 Mean speed and axial load For variable speed and load, lifespan should be calculated with mean values n m et F m. For a variable load at constant speed, the mean load F m is used (figure below). For variable speed and constant load with speed n, the mean speed n m is used (figure below). For a variable load at variable speed, the mean load F m is used. For a variable linear load at constant speed, the mean load F m is used (figure below). n m [min -1 ] : mean speed n 1 n n [min -1 ] : individual speeds q 1 q n [%] : time percentage F m [N] : mean load F ; F 1 F n ; F min ; F max [N] : actual forces

13 Nominal lifespan The nominal lifespan L 10 or L h of a satellite roller screw is attained with a probability of 90%. If greater reliability is required, the nominal lifespan L 10 or L h must be multiplied by the reliability factor f r (table opposite). Durée modifi ée L n = L 10. f r [ revolutions] respectivement L hn = L h. f r [h] Reliability % f r Nominal lifespan of single nuts (with backlash) The nominal lifespan of single nuts is calculated by the following formula: or If the lifespan is predetermined, the dynamic load capacity is calculated as follows: The lifespan in actual hours L hn is calculated by the following formula: The utilisation factor f N is calculated as follows: Nominal lifespan of preloaded nuts For preloaded nuts, it is fi rst necessary to calculate the lifespan of each half of the nut with the corresponding dynamic load capacity C and the mean axial load F ma (including preload). The total lifespan L 10 of the preloaded nut is obtained with the two lifespan values L 10(1) and L 10(2) (in revolutions). L n [revolutions] : modifi ed lifespan (revolutions) L hn [h] : modifi ed lifespan (hours) L 10 [revolutions] : nominal lifespan (revolutions) L h [h] : nominal lifespan (hours) L hn [h] : lifetime in actual hours f r [-] : reliability factor C [N] : dynamic load capacity F m [N] : mean load (single nut with backlash) F ma [N] : mean load (preloaded nut) n m [min-1] : mean speed f N [-] : utilisation factor

14 Rigidity Case 1 : f kn = 0.25 Case 3 : f kn = 2.0 Case 2 : f kn = 1.0 Case 4 : f kn = 4.0 Satellite roller screw rigidity The overall rigidity C ges of a satellite roller screw is made up of the following individual rigidity values: Screw rigidity C S Screw rigidity C S can be determined by the following simplifi ed formula: C me nut rigidity C Sp screw rigidity C L C u bearing rigidity r igidity of the surrounding construction Nut rigidity C me The rigidity C me of a complete satellite roller screw nut can be approximated with the following formula: C me = f m. f K. F 1/3 n [N/µm] f m for single nut ES = 0.75 f m for split nut EF = 1 f m for double nut ED = 1.5 Permissible buckling force F knzul at rotation speed n = 0 Permissible buckling force can be calculated by the following formula: The following condition is set for F n for the C me values shown in the table for standard preloading: F n = F V [N] Fv [N] : preloading force F n [N] : axial load C me [N/µm] : nut rigidity C s [N/µm] : screw rigidity f k [N 2/3 /µm] : rigidity factor f m [-] : correction factor L : free screw length d 0 : nominal diameter of screw F knzul [N] : permissible buckling force f kn [-] : correction factor for bearing type

15 Rotation speed L L Case 1 : f kr = 0.32 Case 3 : f kr = 1.55 L L Case 2 : f kr = 1.0 Case 4 : f kr = 2.24 Permissible rotation speed and axial load Satellite roller screws are restricted by the internal confi guration of the nut, the bearings at the end of the screw and the critical number of revolutions n kr due to fl exural vibration. The value of the permissible speed applied can be: RV : d 0. n RVR : d 0. n Critical speed n kr with axial load Fn = 0 Critical speed is infl uenced by the axial load. It can be calculated on request for every satellite roller screw confi guration. When the correct screw end bearings are chosen, their maximum speed will have no effect on the desired speed. All that needs to be determined is the critical speed n kr for fl exural vibration. The critical speed n kr for fl exural vibration can be calculated by the formula below. The correction factor f kr depends on the type of bearing and the clamping conditions (figure above). The calculation is based on the assumption that satellite roller screw nuts provide no guidance and the bearings at the screw end are considered rigid in the radial direction. The permissible critical speed can be calculated by taking the bearing type into account: n [min -1 ] : rotation speed n kr [min -1 ] : critical rotation speed n krzul [min -1 ] : permissible critical rotation speed L : free screw length d 0 : nominal diameter of screw f kr [-] : correction factor for bearing type 0,8 [-] : safety factor

16 Driving torque F Screw lead P J 2 v i = D 1 D 2 M M J 1 J M n M Driving torque All the values for motor rating can be calculated by the formulas below. Note that the load-free torque M v must be taken into account for preloaded nuts (based on preloading F v ). For single nuts with backlash, the formula is: M v = 0 [Nm] Motor driving torque M M at constant speed Load-free torque «Ascent» load torque «Descent» load torque The frictional forces of the guide slideway must be taken into account in feed force F. Motor driving torque If, as is possible in «Descent» mode, the motor driving torque is negative, the motor must have a brake. Motor driving power d : external diameter of screw d 2 : core diameter of screw P : screw lead L : length of satellite roller screw m T [kg] : mass to move D 1 : diameter of driving wheel D 2 : diameter of driven wheel i [-] : reduction ratio F [N] : feed force F v [N] : preloading force F a [N] : acceleration force M v [Nm] : load-free torque M L1 [Nm] : «ascent» load torque at constant speed M L2 [Nm] : «descent» load torque at constant speed M M [Nm] : motor driving torque M La [Nm] : load torque on acceleration M B [Nm] : acceleration torque M Ma [Nm] : motor driving torque on acceleration M R [Nm] : frictional torque of screw bearings J M [kgm 2 ] : moment of inertia of motor

17 Motor driving torque M Ma with acceleration The rotary moment of inertia of screw J R is a rough estimate. We shall be happy to calculate the exact value on request. Load torque Translatory moment of inertia Rotary moment of inertia (screw) Sum of reduced moments of inertia Motor speed Acceleration torque M B = f (n M ) Acceleration torque M B = f (s B ) Acceleration time t B = f (n M ) Acceleration time t B = f (s B ) Rotation speed reached after acceleration Path travelled during acceleration Motor driving torque Motor driving power J R [kgm 2 ] : rotary moment of inertia of screw J T [kgm 2 ] : translatory moment of inertia of screw J [kgm 2 ] : moment of inertia J 1 [kgm 2 ] : moment of inertia of driving wheel J 2 [kgm 2 ] : moment of inertia of driven wheel P M [W] : driving power of motor at constant speed P Ma [W] : driving power of motor on acceleration s B : acceleration path t B [s] : acceleration time v [m/s] : speed rate n M [min -1 ] : rotation speed of motor η [-] : mechanical effi ciency of gearing η 1 [-] : mechanical effi ciency of satellite roller screw for «ascent» η 1 = 0,71 0,89 η 2 [-] : mechanical effi ciency of satellite roller screw for «descent» η 2 = 0,61 0,85 c [-] : coeffi cient of friction referred to preloading c = 0,1 0,5 ( for effi ciencies η 1 + η 2 see page 6)

18 Calculation example Satellite roller screws RV 20 x 5 Nominal diameter : d 0 = 20 mm Lead : P = 5 mm Nut : split nut (EF), preloaded Mounting position : horizontal Load direction : both sides Rapid mode : one side, opposite to working load N Operating mode Time percentage q [%] Rotation speed n [min -1 ] Axial load F n [N] 1 Peak load q 1 = 5 n 1 = 15 F 1 = Roughing feed q 2 = 40 n 2 = 110 F 2 = Finishing feed q 3 = 50 n 3 = 70 F 3 = Rapid q 4 = 5 n 4 = 1700 F 4 = 1150 Mean speed Preloading Preloading is defi ned for the «fi nishing feed» operating mode (F 3 = 4200 N). Load on nut half 1 Nut half 1 is loaded in operating modes 1, 2 and 3. As F1, F2 eand F F v : Load on nut half 2 Nut half 1 is only partly loaded in operating mode 4. As F4 = 1150 N < 2.83 F v : Half nut 2 is loaded in operating mode 4. Half nut 2 is not loaded in operating modes 1, 2 and 3. As F 4 < F v, on a : Charge Mean load Nut 1 Nut 2 Lifespan Dynamic load capacity of a nut C = N Half nut 1 Half nut

19 Total lifespan Lifespan in hours (with utilisation factor f N = 0.6) Nut rigidity Satellite roller screw rigidity Free length between fi xed bearing and nut Nominal diameter of screw 1 = 1000 mm d 1 = 20 mm Bearing rigidity Total rigidity of satellite roller screw system Driving torque Driving torque MM is calculated for the peak load of F 1 = 8300 N. The screw is directly driven by the motor (i = 1) : Load-free torque: Load torque: Frictional torque of bearings: Peak driving torque of motor at constant speed: Motor driving power reaches its peak in rapid mode with F 4 = 1150 N. Moment en Load torque: : Peak driving power of motor at constant speed:

20 Lubrication As a general rule, the same lubricants are used for satellite roller screws as for roller bearings, i.e. either oil or grease. The type of lubricant used mostly depends on operating and maintenance conditions. Unless the customer explicitly instructs otherwise, standard Rollvis grease is applied at the factory. Oil lubrication Circulating mineral oils with EP additives to enhance resistance to aging and corrosion in compliance with CL based on DIN 51517, part 2, are especially suitable for the lubrication of satellite roller screws. Speed, ambient temperature and operating temperature are determining factors in the choice of viscosity. The amount of oil required depends on the screw diameter, the number of supporting rollers and the amount of heat to dissipate. 1 cm 3 /h (for small screw diameters) to 30 cm 3 /h (for large screw diameters) can be used as reference values. The shortest possible lubrication intervals ( 5 minutes) are recommended for high loads and longer intervals (5 minutes to 1 hr) for low loads. Automatic lubrication is recommended for high loads and speeds. For immersion lubrication, the oil level should be such that the bottommost roller is completely submerged in the oil. The amount of oil and the oil-change intervals depend on the loading and installation. The viscosity of the oil should be chosen to enable an adequate fi lm of lubricant to form on the contact surfaces. Figure a shows the operating viscosity ν κ to achieve for the mean speed of the satellite roller screw and screw diameter. Viscosity ν κ ensures a state of lubrication to fulfi l the nominal lifespan provided the lubrication system is free of foreign bodies. Nominal viscosity can be calculated on the basis of viscosity ν κ with the viscosity-temperature diagram (diagram ν-t, figure b) and the operating temperature. Nominal viscosity is the viscosity of oil at 40 C. Viscosity classes ISO VG (DIN 51519) are plotted in diagram ν-t. Figure a shows the nominal diameters of RV satellite roller screws. The diameters of RVR satellite roller screws are slightly different. The requisite operating viscosity values can be obtained by interpolation. Intermediate values can be obtained from the steps. These must be rounded up to the nearest viscosity value. The operating temperature must be known or estimated to calculate nominal viscosity. The operating temperature must be measured on the nut after stabilisation. A suitable oil can be found in oil suppliers lists with the nominal viscosity at 40 C. In general, an operating temperature of 30 C can be taken as a basis for selecting a lubricant. Example: Satellite roller screw RV 39 x 10 Mean operating speed: n m = 1400 min -1 Operating temperature (estimated): t = 25 C In figure a, for a number of revolutions nm = 1400 min -1 and a nominal diameter of 39mm, the nominal viscosity is ν κ = 33 mm 2 /s. In diagram ν-t (figure b), the 25 C temperature and 34 mm 2 /s viscosity lines intersect between ISO VG 15 and ISO VG 22. The oil to choose will be in viscosity class VG 22. A suitable CLP (DIN 51517) or HLP (DIN 51525) oil can be selected from this class. Grease lubrication The best grease lubricants to use are KP (DIN 51825, part 3) with a consistency factor of 2. Lubrication intervals depend on the screw arrangement, size and operating conditions. Rollvis can provide recommendations for any type of application

21 mm [ 2 s ] ν κ operating viscosity Mean screw rotation speed n m [min -1 ] Nominal diameter d Figure a Figure b Operating temperature t [ C] ν mm [ 2 κ operating viscosity s ]

22 Handling advice Assembly If possible, the nut and screw should not be dismantled. However, should this be necessary, an assembly sleeve must be used. External diameter d 3 of assembly sleeve: 0 d 3 = d 2-0,05 (d 2 = screw core diameter) Screw assembly Montage de la vis The following points must be followed when assembling the screw: 1 Align the screw and slide guideways axially parallel. 2 Fix the nut in housing. 3 Run the nut along the entire length of the thread and check the screw for ease of movement CAUTION RV screws always have a multiple-start thread. If the friction torque is different after the nut is reassembled, the nut must be taken off again and refitted on the next thread start until friction torque is correct! Handling Please read the following handling instructions carefully. To ensure optimal operation and a long lifespan for satellite roller screws, the following points must be scrupulously complied with. If in doubt, please contact Rollvis. Lubrication Satellite roller screws are greased prior to shipment (unless oil lubrication is requested). Do not remove this grease. Only use this type of grease for relubrication. Transport Handle screws with care: do not drop them or damage the thread. Installation Do not unscrew the nut (or only with an assembly sleeve). Carefully align satellite roller screws parallel to the guideways. Alignment errors will damage satellite roller screws. Storage Only remove satellite roller screws from their original packing just before installation. Bending Avoid applying radial forces to the nut

23 program Preference Type RV diameters of 3.5 to Type RV diameters of 15 to Type RV diameters of 25 to Type RV diameters of 39 to Type RV diameters of 51 to Type RV diameters of 80 to Type BRV diameters of 8 to Type RVR diameters of 8 to

24 Type RV - Ground screws Flange shapes and Drilling s drawings Shape A Shape B Drilling s drawing 1 Single nut, with backlash and double nut Split nut, preloaded, without backlash Split nuts, preloaded, preloading torque Without wipers With wipers Efficiency [N 2/3 /µm] Type D x P N d0 d1 d2 C Co F K C Co F K F V M V D1 D2 D5 D7 L1 L1 L2 L3 L4 L5 L6 RV 3.5 x RV 5 x RV 5 x RV 5 x RV 7 x RV 7 x RV 7 x RV 7 x RV 7 x RV 8 x RV 8 x RV 8 x RV 8 x RV 8 x RV 8 x RV 10 x RV 10 x RV 10 x RV 10 x RV 10 x RV 12 x RV 12 x RV 12 x RV 12 x RV 12 x RV 12 x Maximum backlash of single nuts: 0.03mm (can be less on request). If possible, provide a lubrication hole in the nut (contact Rollvis for feasibility and position). [N 2/3 /µm] [N] [Ncm] Terms used in tables P Lead d1 External diameter F k Rigidity factor D Reference diameter d2 Thread bottom diameter F v Preloading force N Number of starts C Dynamic load capacity M v Load-free torque due to preloading d0 Nominal diameter Co Static load capacity

25 Type RV - Ground screws Drilling s drawing 2 Drilling s drawing 3 Drilling s drawing 4 Single nut, with backlash and double nut Split nut, preloaded, without backlash Split nuts, preloaded, preloading torque Without wipers With wipers Efficiency [N 2/3 /µm] Type D x P N d0 d1 d2 C Co F K C Co F K F V M V D1 D2 D5 D7 L1 L1 L2 L3 L4 L5 L6 RV 15 x RV 15 x RV 15 x RV 15 x RV 15 x RV 15 x RV 20 x RV 20 x RV 20 x RV 20 x RV 20 x RV 20 x RV 20 x RV 21 x RV 21 x RV 21 x RV 21 x RV 21 x RV 21 x RV 21 x RV 23 x RV 23 x RV 23 x RV 23 x RV 23 x RV 23 x RV 23 x Maximum backlash of single nuts: 0.03mm (can be less on request). If possible, provide a lubrication hole in the nut (contact Rollvis for feasibility and position). [N 2/3 /µm] [N] [Ncm] Terms used in tables P Lead d1 External diameter F k Rigidity factor D Reference diameter d2 Thread bottom diameter F v Preloading force N Number of starts C Dynamic load capacity M v Load-free torque due to preloading d0 Nominal diameter Co Static load capacity

26 Type RV - Ground screws Flange shapes and Drilling s drawings Shape A Shape B Drilling s drawing 1 Single nut, with backlash and double nut Split nut, preloaded, without backlash Split nuts, preloaded, preloading torque Without wipers With wipers Efficiency [N 2/3 /µm] Type D x P N d0 d1 d2 C Co F K C Co F K F V M V D1 D2 D5 D7 L1 L1 L2 L3 L4 L5 L6 RV 25 x RV 25 x RV 25 x RV 25 x RV 25 x RV 25 x RV 27 x RV 27 x RV 27 x RV 27 x RV 27 x RV 27 x RV 30 x RV 30 x RV 30 x RV 30 x RV 30 x RV 30 x RV 30 x RV 30 x RV 30 x RV 36 x RV 36 x RV 36 x RV 36 x RV 36 x RV 36 x RV 36 x RV 36 x Maximum backlash of single nuts: 0.03mm (can be less on request). If possible, provide a lubrication hole in the nut (contact Rollvis for feasibility and position). [N 2/3 /µm] [N] [Ncm] Terms used in tables P Lead d1 External diameter F k Rigidity factor D Reference diameter d2 Thread bottom diameter F v Preloading force N Number of starts C Dynamic load capacity M v Load-free torque due to preloading d0 Nominal diameter Co Static load capacity

27 Type RV - Ground screws Drilling s drawing 2 Drilling s drawing 3 Drilling s drawing 4 Single nut, with backlash and double nut Split nut, preloaded, without backlash Split nuts, preloaded, preloading torque Without wipers With wipers Efficiency [N 2/3 /µm] Type D x P N d0 d1 d2 C Co F K C Co F K F V M V D1 D2 D5 D7 L1 L1 L2 L3 L4 L5 L6 RV 39 x RV 39 x RV 39 x RV 39 x RV 39 x RV 39 x RV 39 x RV 39 x RV 39 x RV 44 x RV 44 x RV 44 x RV 44 x RV 44 x RV 48 x RV 48 x RV 48 x RV 48 x RV 48 x RV 48 x RV 48 x RV 48 x RV 48 x RV 48 x RV 48 x RV 48 x RV 48 x RV 48 x RV 48 x Maximum backlash of single nuts: 0.03mm (can be less on request). If possible, provide a lubrication hole in the nut (contact Rollvis for feasibility and position). [N 2/3 /µm] [N] [Ncm] Terms used in tables P Lead d1 External diameter F k Rigidity factor D Reference diameter d2 Thread bottom diameter F v Preloading force N Number of starts C Dynamic load capacity M v Load-free torque due to preloading d0 Nominal diameter Co Static load capacity

28 Type RV - Ground screws Flange shapes and Drilling s drawings Shape A Shape B Drilling s drawing 1 Efficiency Single nut, with backlash and double nut [N 2/3 /µm] Split nut, preloaded, without backlash Split nuts, preloaded, preloading torque Without wipers With wipers Type D x P N d0 d1 d2 C Co F K C Co F K F V M V D1 D2 D5 D7 L1 L1 L2 L3 L4 L5 L6 RV 51 x RV 51 x RV 51 x RV 51 x RV 51 x RV 60 x RV 60 x RV 60 x RV 60 x RV 60 x RV 60 x RV 60 x RV 60 x RV 60 x RV 60 x RV 60 x RV 64 x RV 64 x RV 64 x RV 64 x RV 64 x RV 64 x RV 70 x RV 70 x RV 70 x RV 70 x RV 75 x RV 75 x RV 75 x RV 75 x RV 75 x RV 75 x RV 75 x RV 75 x Maximum backlash of single nuts: 0.03mm (can be less on request). If possible, provide a lubrication hole in the nut (contact Rollvis for feasibility and position). [N 2/3 /µm] [N] [Ncm] Terms used in tables P Lead d1 External diameter F k Rigidity factor D Reference diameter d2 Thread bottom diameter F v Preloading force N Number of starts C Dynamic load capacity M v Load-free torque due to preloading d0 Nominal diameter Co Static load capacity High capacity defi nition

29 Type RV - Ground screws Drilling s drawing 2 Drilling s drawing 3 Drilling s drawing 4 Efficiency Single nut, with backlash and double nut [N 2/3 /µm] Split nut, preloaded, without backlash Split nuts, preloaded, preloading torque Without wipers With wipers Type D x P N d0 d1 d2 C Co F K C Co F K F V M V D1 D2 D5 D7 L1 L1 L2 L3 L4 L5 L6 RV 80 x RV 80 x RV 80 x RV 80 x RV 80 x RV 80 x RV 80 x RV 80 x RV 80 x RV 92 x RV 92 x RV 92 x RV 100 x RV 100 x RV 100 x RV 100 x RV 100 x RV 100 x RV 100 x RV 100 x RV 100 x RV 120 x RV 120 x RV 120 x RV 120 x RV 120 x RV 120 x RV 120 x RV 120 x RV 120 x RV 120 x RV 135 x RV 135 x RV 135 x RV 135 x RV 150 x RV 150 x RV 150 x RV 150 x Maximum backlash of single nuts: 0.03mm (can be less on request). If possible, provide a lubrication hole in the nut (contact Rollvis for feasibility and position). Terms used in tables P Lead d1 External diameter F k Rigidity factor D Reference diameter d2 Thread bottom diameter F v Preloading force N Number of starts C Dynamic load capacity M v Load-free torque due to preloading d0 Nominal diameter Co Static load capacity High capacity defi nition [N 2/3 /µm] [N] [Ncm]

30 Type BRV - Rolled screws Flange shapes and Drilling s drawings Shape A Shape B Drilling s drawing 1 Single nut, with backlash and double nut Split nut, preloaded, without backlash Split nuts, preloaded, preloading torque Without wipers With wipers Efficiency [N 2/3 /µm] Type D x P N d0 d1 d2 C Co F K C Co F K F V M V D1 D2 D5 D7 L1 L1 L2 L3 L4 L5 L6 BRV 8 x BRV 12 x BRV 12 x BRV 15 x BRV 15 x BRV 20 x BRV 20 x BRV 23 x BRV 23 x BRV 23 x BRV 27 x BRV 27 x BRV 30 x BRV 39 x BRV 39 x BRV 44 x Maximum backlash of single nuts: 0.03mm (can be less on request). If possible, provide a lubrication hole in the nut (contact Rollvis for feasibility and position). [N 2/3 /µm] [N] [Ncm] Terms used in tables P Lead d1 External diameter F k Rigidity factor D Reference diameter d2 Thread bottom diameter F v Preloading force N Number of starts C Dynamic load capacity M v Load-free torque due to preloading d0 Nominal diameter Co Static load capacity

31 Type RVR - Ground screws - System with rollers recycling Drilling s drawing 2 Drilling s drawing 3 Drilling s drawing 4 Efficiency Single nut, with backlash and double nut [N 2/3 /µm] Split nut, preloaded, without backlash [N 2/3 /µm] Split nuts, preloaded, preloading torque [N] [Ncm] Without wipers With wipers Type D x P N d0 d1 d2 C Co F K C Co F K F V M V D1 D2 D5 D7 L1 L1 L2 L3 L4 L5 L6 RVR 8 x RVR 8 X RVR 8 X RVR 10 x RVR 10 X RVR 10 X RVR 12 x RVR 12 X RVR 12 X RVR 16 x RVR 16 X RVR 16 X RVR 20 X RVR 20 X RVR 20 X RVR 25 X RVR 25 X RVR 32 X RVR 32 X RVR 40 X RVR 40 X RVR 50 X RVR 50 X RVR 50 X RVR 50 X RVR 63 X RVR 63 X RVR 63 X RVR 80 X RVR 80 X RVR 80 X RVR 100 X RVR 100 X RVR 100 X RVR 125 x Maximum backlash of single nuts: 0.03mm (can be less on request). If possible, provide a lubrication hole in the nut (contact Rollvis for feasibility and position). Terms used in tables P Lead d1 External diameter F k Rigidity factor D Reference diameter d2 Thread bottom diameter F v Preloading force N Number of starts C Dynamic load capacity M v Load-free torque due to preloading d0 Nominal diameter Co Static load capacity

32 Applications The great flexibility of Rollvis SA means it can make all types of screws and nuts as shown in the examples below: RV 4 x 1 RV 8 x 2 RV 12 x 8 RV 30 x 30 RV 48 x 10 RVR 100 x

33 RV 20 x 3 RV 36 x 3 RV 39 x 5 RVR 12 x 1 RV 8 x 5 RV 25 x

34 Applications ( ctd.) RV 12 x 8 RV 15 x 5 RV 39 x 10 RV 12 x 7 RV 100 x 10 RV 30 x