Timken2MM9115WIDULSuper Precision Angular Contact Ball Bearing 75x115x20 mm, 15° Contact Angle, Duplex Light Preload, Phenolic Cage, 2 Pcs

Product Description

What this part is

A matched pair of Fafnir super-precision angular contact ball bearings, part number 2MM9115WI-CR-DUL. Bore is 75 mm, outside diameter 115 mm and each ring width 20 mm, giving an ISO 7015 envelope in the light dimension series. Fafnir is the super-precision line of the Timken Company.

Decoding the designation

The leading 2 of 2MM sets a 15° contact angle, where 3MM sets 25°. The MM prefix carries super-precision class P4S, ABEC 7 dimensionally with ABEC 9 running accuracy, which is why the same part reads as 7015 C CR DUL P4S in ISO form. The leading 9 in 9115 places the bearing in the ISO 70 light series, so the outside diameter is 115 mm rather than the 130 mm of a 7215. WI is the super-precision angular contact family, CR a phenolic cage riding on the outer ring land, DU a universally ground duplex pair and L light preload.

What these specs mean in practice

A 15° contact angle carries less thrust and permits higher speed than a 25° angle, and light preload removes internal clearance while keeping running torque and heat generation low. The 70 light series gives a thinner cross-section for the same bore, lowering mass and raising limiting speed at the cost of load capacity. A phenolic land-riding cage has low mass and retains oil in the resin, at a lower temperature ceiling than bronze or steel.

Quantity and configuration

2 Pcs, supplied as one duplex pair ground for light preload. No spacer rings, lock nut or housing are included.

Fitting notes

Universally ground rings reach the designed preload when the pair is clamped solid against the flush ground faces, without shimming, and the arrangement is set by which faces are brought together. Handling is by the outer ring on a clean surface, and a phenolic cage is kept clear of solvents that attack the resin.

Interchange guidance

Same-spec equivalents are the 7015 C P4 DUL forms: SKF 7015 CD/P4A in a light-preload duplex arrangement, FAG B7015-C-T-P4S-UL, NSK 7015 CTR DUL P4 and RHP 7015CTDULP4. A 7015 AC or A5 variant is a related size at 25° or 30° and changes the thrust and speed balance, so it is not a substitution. 2MM9115WI-CR-DUM and -CR-DUH share the envelope and angle at higher preload.