Fafnir2MM9118WISUM-KGSuper-Precision Angular Contact Ball Bearing 90x140x24 mm 15° Medium Preload Snap Ring ABEC 7/9

Product Description

What this part is

A Fafnir 2MM9118WI-SUM-KG super-precision single-row angular contact ball bearing. Bore 90 mm, outside diameter 140 mm, width 24 mm. Open on both faces, universally ground, supplied with the snap ring fitted in the outer-ring groove.

Decoding the designation

2MM — 15° contact angle in the Fafnir scheme; the MM prefix carries the P4S build9118 — leading 9 marks the ISO 70 light series, 90 mm bore, so the ISO equivalent is 7018-CWI — super-precision spindle bearing seriesSU — single universally groundM — medium preload

What these specs mean in practice

P4S is the Fafnir super-precision grade covering ABEC 7 dimensional tolerance with ABEC 9 running accuracy. The 15° contact angle favours speed and radial stiffness; medium preload raises stiffness over the light grade and runs warmer. The 70 light series gives a thinner cross-section than a 72-series 7218 at a lower load rating and higher speed capability.

Published specifications

Bore: 90 mmOutside diameter: 140 mmWidth: 24 mmContact angle: 15°Precision: P4S — ABEC 7 / ABEC 9Preload: mediumRows: 1Closure: openSnap ring: fitted

Quantity and configuration

Single universally ground bearing with snap ring. 1 Pc per sale unit.

Fitting notes

Thrust is carried in one direction only, so the bearing runs against an opposing bearing or a housing shoulder. The snap ring locates the outer ring axially against a plain housing bore, which removes the need for a machined shoulder on that side.

Interchange guidance

Same-spec equivalents at 15°, super precision, medium preload: RHP 7018CTSUMP4, FAG B7018C.T.P4S.UM, SKF 7018 CD/P4A, NSK 7018CTRSUMP4. Versions without the snap ring share the raceway geometry but not the outer-ring groove, and are related builds rather than a drop-in for a plain-bore housing.