Fafnir2MM9117WIDUHSuper-Precision Angular Contact Bearing Matched Pair 85x130x22 mm 15° Heavy Preload ABEC 7/9

Product Description

What this part is

A Fafnir 2MM9117WI-DUH matched duplex pair of super-precision single-row angular contact ball bearings. Each bearing is 85 mm bore, 130 mm outside diameter, 22 mm wide, giving 44 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 build9117 — leading 9 marks the ISO 70 light series, 85 mm bore, so the ISO equivalent is 7017-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 preload grades and the least deflection under cutting load, at the cost of running temperature and top speed. Paired with the 15° angle it suits spindles that hold position under load rather than chase maximum rpm.

Published specifications

Bore: 85 mmOutside diameter: 130 mmWidth: 22 mm per bearing, 44 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 7017CTDUHP4, FAG B7017C.T.P4S.UH, SKF 7017 CD/P4ADGC, NSK 7017CTRDUHP4. The light and medium preload versions of the same designation share the envelope with different axial stiffness and are related builds rather than interchanges.