Fafnir2MM219WISuper-Precision Angular Contact Ball Bearing, 95 mm Bore, 170 mm OD, 32 mm Width, Open, 15 Degree Contact Angle, ABEC 7 / P4S

Product Description

What this part is

A Fafnir super-precision single-row angular contact ball bearing, 95 mm bore, 170 mm outside diameter, 32 mm width. Open on both faces, phenolic cage, steel balls and rings. Fafnir is Timken’s super-precision line, so this part also appears under the Timken name.

Decoding the designation

In the Fafnir super-precision scheme the leading 2 of 2MM sets a 15° contact angle. The MM prefix carries P4S running accuracy, equivalent to ABEC 7 with ABEC 9 geometric tolerances on the critical features. The absence of a leading 9 places the bearing in the ISO 72 dimension series, which is why 219 corresponds to the 7219 envelope. WI identifies the super-precision angular contact family.

What these specs mean in practice

A 15° contact angle favours speed and radial stiffness over thrust capacity: it accepts a higher limiting speed than a 25° bearing of the same envelope and carries proportionally less axial load. P4S accuracy holds bore and outside diameter runout tight enough for machine-tool spindle work, where the bearing sets the shaft’s geometric position. The phenolic cage is light and self-lubricating, which suits high speed, and it sets a working temperature ceiling of about 100 °C.

Quantity and configuration

1 Pc. Single bearing, open both faces, supplied without snap ring.

Fitting notes

Angular contact bearings of this type take thrust in one direction only, so a mounting is arranged as a pair or set against a second bearing or a locating shoulder. The high side of the outer ring, marked on the ring face, faces the thrust load. Installation is by cold press or induction heat on the inner ring, avoiding any load path through the balls.

Interchange guidance

Same-spec equivalents at 15° and P4 class are the SKF 7219 CD/P4A and the NSK 7219CTYSULP4. A 3MM219WI is the same envelope at a 25° contact angle, and a 7219 in a lower precision class is the same envelope at a coarser accuracy grade; both are related sizes rather than substitutions. Bearings supplied as universally ground singles or matched duplex pairs carry SU or DU codes that this part number does not, so a set requirement is not met by this designation alone.