The MMN/MMF double-row design supports bidirectional axial loads, as well as combination radial loads and overturning moments. A 60° contact angle and a maximum complement of balls boosts spindle stiffness and axial rigidity. Optional ceramic bearing balls and special greases further increase stiffness, speed, and acceleration ratings.

A pair of low-torque integral contact seals expels contaminants to extend bearing service life in harsh operating environments. The bearings are prepacked with high-performance grease and allow for in-service relubrication.

All Fafnir ball-screw support bearings are made to a precision-ground width tolerance five times tighter than ABEC 9/ISO P2 standards. This advancement, combined with a new marking of the individual set width, virtually eliminates the need to regrind end caps for proper fit. The bearings also maintain ABEC9/ISO P2 axial running tolerances to reduce runout and improve repeatability in precision machine tools. They are made from steel that is nearly free of impurities and inclusions, which also improves service life and durability.

Fafnir ball-screw support bearings come in flanged and nonflanged designs to accommodate standard and rotating-nut mountings. Housed cartridge and pillow block units facilitate bolting to machine-tool surfaces. Single-row bearings come in bore sizes from 12 to 100 mm, and double-row bearings, from 12 to 60 mm.

The Timken Co., 1835 Dueber Ave. SW, Canton, OH 44706, (800) 964-2626, timken.com