Ball screws
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SNR LiNEAR MOTION; BALL SCREWS www.ntn-snr.com

For almost a century, SNR has designed, developed and manufactured bearings to meet the most demanding of applications. In April 2008, SNR and the Japanese Group NTN joined forces. As one the 3 largest companies in the manufacture of bearings, our group offers its customers added value in terms of service, quality and products. The NTN-SNR Group is distinguished by its global presence and by its company-wide quality assurance system. We have been active in linear ball rail systems since 1985 and our complete range, based on innovative, high-quality products, has developed...

Ball screws overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Standard programme. Rolled. Tolerance class 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Special programme whirled or ground. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Standard programme Ball screws . . . . . . . . . . . . . . . . . . . . . . . 4 . . Rolled models (tolerance class 7) for the compact DIN Nut (Type SC/DC). . . . . . . . . . . . . . . . . . . . . 4 Rolled models (tolerance class 7) for nut...

Standard programme . Rolled . Tolerance class 7 . Materials: Spindles Ok55 Sealing system for ball screws: Smooth running sealing Rolled, right-hand thread Rolled, left-hand thread Available from stock Available from ex stock Not a standard programme, request through project

Special programme whirled or polished Wiper: PTFE wipers, brush wipers, felt wipers etc. ATC coating e.g. for use in corrosive media, food industry. The ATC coating consists of more than 98% pure chromium. It is an extremely hard, crack-free, dome-shaped, precise, very thin and highly pure chromium coating.

d Reference diameter [mm] do Nominal diameter [mm] di Outside diameter [mm] d2 Diameter at the thread root [mm] P Pitch [mm] Lmax. Maximum length of screw [mm] Rolled models (tolerance class 7) for the compact DIN Nut (Type Sc/DC)

Rolled models (tolerance class 7) for nut (type SK, Cl, SU/DU, SE)

Ball nut sizes shown In bold are available ex stock. * Number of circuits P-Pitch

Type CI single cylindrical nut for rolled screws Ball nut sizes shown In bold are available ex stock. * Number of circuits P-Pitch

Standard programme Ball nut Type SC single compact flange nut to DIN 69051, for rolled screws Ball nut sizes shown In bold are available ex stock. * Number of circuits P-Pitch NTN. with You

Type DC double compact flange nut to DIN 69051, for rolled screws Ball nut sizes shown In bold are available ex stock. * Number of circuits P-Pitch

Type SU single flange nut to DIN 69051, for rolled screws from size 04005 Form B Ball nut sizes shown in bold are available ex stock. * Number of circuits P-Pitch

Type DU double flange nut to DIN 69051, for rolled screws Ball nut sizes shown in bold are available ex stock. * Number of circuits P-Pitch

Type SE single wide pitch nut for rolled screws Ball nut sizes shown in bold are available ex stock. * Number of circuits Ground on request

Type SH single threaded nose nuts for rolled screws Ball nut sizes shown in bold are available ex stock. * Number of circuits Ground on request

Fixed bearing unit PBUF with angular contact ball bearing The fixed bearing units consist of: • Pillow block housing made of steel with stop edges on both sides, direct drive adaption and lubrication option • Double row angular contact ball bearing with a contact angle of 58° • Slotted nut with radial clamping • Thread ring Suitable for standard spindle ends type F3, F4 (see page 21) Ma - Tightening torque slotted nut MG - Tightening torque threaded pin

Floating bearing unit PBUL with deep grooved ball bearing DIN 625 The floating bearing unit consists of: • Pillow block housing made of steel • Deep grooved ball bearing DIN 62...-2RS • Retaining ring DIN 471 • Cover Suitable for standard spindle ends type S2 (see page 22)

Fixed bearing unit BK The fixed bearing unit consists of: • Pillow block housing made of black oxided steel • Two angular contact ball bearings • Two seals with contact rings • Slotted nut Suitable for standard spindle ends type F1, F2 (see page 21)

Fixed bearing unit EK The fixed bearing unit consists of: • Pillow block housing made of black oxided steel • Two angular contact ball bearings • Two seals with contact rings • Slotted nut Suitable for standard spindle ends type F1, F2 (see page 21)

Floating bearing unit BF The floating bearing unit consists of: • Bearing housing made of black oxided steel • Deep grooved ball bearing • Retaining ring Suitable for standard spindle ends type S1 (see page 22)

Machining for fixed bearings

Machining for floating bearings

Travel variation and travel deviation The tolerance classes of the SNR ball screws are defined in accordance with ISO 3408. The tolerance classes T0-T5 are determined according to the mean travel variation and the tolerance of the travel deviations over the entire usable travel lu. For tolerances T7-T10 the mean deviation over the length 300 mm is defined at anywhere over the length of thread. l0 Travel deviation Actual travel variation The usable travel is the stroke plus length of the ball nut. le The overrun is the axial travel beyond the usable travel serving the safety purpose. The...

Permissible variances of the intermediate travel variation and the travel fluctuation Tolerance of the travel variation within an interval of 300 mm and a turn (international standards). Tolerance class

Measurement of the concentricity, ^5 of the outer diameter of the ball screw spindle over the length for determining the straightness relative to AA£

Nominal diameter do in mm Measurement of the axial runout variation ^ of the contact surface for bearing relative to AA‘

Measurement of the axial runout variation t9 of the contact surface of the ball nut relative to AA‘ (only for preloading ball nuts) Flange diameter t9p In pm per tolerance class D2 In mm