Fafnir2MM3MM9122WITSuper-Precision Angular Contact Ball Bearing Set 110x170x28 mm, ISO 70 Light Series, P4S Precision, Triplex Light Preload, 3 Pcs

Product Description

What this part is

A set of three Fafnir 9122WI super-precision angular contact ball bearings, 110 mm bore by 170 mm outside diameter by 28 mm wide, ground as a triplex stack at light preload. Fafnir is Timken’s super-precision line.

Decoding the designation

The MM prefix carries P4S precision, equivalent to ABEC 7/9. The leading 9 in 9122 places the bearing in the ISO 70 light dimension series, giving an ISO base number of 7022, and the 22 size code gives a 110 mm bore. WI marks the super-precision angular contact family and TUL a triplex set at light preload.

What these specs mean in practice

A triplex stack puts three rows in one bearing position. Arranged with two rows facing one way and one the other, it carries heavy thrust in the primary direction and locates the shaft in the other, which is the usual arrangement at the front bearing of a loaded spindle. Light preload keeps the frictional heat of three rows manageable at speed.

Quantity and configuration

Three bearings, ground as a matched triplex set. The set is open, with no seals or snap rings.

Fitting notes

The three are installed together in the ground order and orientation, since the offsets are matched across the stack rather than within a pair. Mounting is onto a clean straight journal against a square shoulder, and the stack is clamped without shims.

Interchange guidance

The ISO base number is 7022, so the size envelope matches a 7022-series angular contact bearing from any maker. A triplex-ground set is only interchangeable with another triplex set of the same angle and preload; a duplex pair or a single universal bearing in the same envelope is a related size.