Fafnir2MM9122WIDUHSuper-Precision Angular Contact Bearing Matched Pair 110x170x28 mm 15° Heavy Preload ABEC 7/9

Product Description

What this part is

A Fafnir 2MM9122WI-DUH matched duplex pair of super-precision single-row angular contact ball bearings. Each bearing is 110 mm bore, 170 mm outside diameter, 28 mm wide, giving 56 mm total stack width. Open on both faces, universally ground as a set.

Decoding the designation

2MM — 15° contact angle in the Fafnir scheme; the MM prefix carries the P4S build9122 — leading 9 marks the ISO 70 light series, 110 mm bore, so the ISO equivalent is 7022-CWI — super-precision spindle bearing seriesDU — duplex, ground as a matched setH — heavy preload

What these specs mean in practice

Heavy preload gives the highest radial and axial stiffness of the three grades and the least spindle deflection under load, at the cost of running temperature and top speed. The 15° angle favours speed and radial stiffness over thrust, so the combination suits stiff spindles running at moderate rpm.

Published specifications

Bore: 110 mmOutside diameter: 170 mmWidth: 28 mm per bearing, 56 mm stackedContact angle: 15°Precision: P4S — ABEC 7 / ABEC 9Preload: heavy, factory matchedRows: 1 per bearingClosure: open

Quantity and configuration

Matched duplex pair. 2 Pcs per sale unit.

Fitting notes

Each bearing carries thrust in one direction; the pair mounted back-to-back or face-to-face covers both. The etched marks on the outer rings align to hold the matched offset as ground.

Interchange guidance

Same-spec matched pairs at 15°, super precision, heavy preload: RHP 7022CTDUHP4, FAG B7022C.T.P4S.UH, SKF 7022 CD/P4ADGC, NSK 7022CTRDUHP4. The 25° 3MM9122WI shares the envelope and is a related size rather than an interchange.