NK15-16-XL bearing: complete specifications & equivalents

Specification table

Source: catalog reference (HR1 2026-09-25) · extracted 2026-09-30

Parameters extracted from the official FAG Rolling Bearings catalogue (HR1 2026-09-25); FAG® is a trademark of Schaeffler Technologies AG & Co. KG, used here for identification only — mpnbase is not an authorized FAG/Schaeffler distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at schaeffler.com.

Cross references & equivalents

Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.

How the NK15-16-XL model number is decoded

envelope 15×23×16 mm: 15 mm seat is the hardened and ground shaft journal itself — there is no inner ring, with a thin 4.0 mm radial section packed with small-diameter needle rollers C is 12.1 kN and C0 12.7 kN at the 15 mm seat; the C/C0 ratio of 0.95 is characteristic of a needle bearing — high static rating relative to dynamic in a compact 23 mm outside diameter the fatigue load limit Cur is 2.36 kN, the limiting speed 23,900 r/min and the thermal reference speed 17,300 r/min; for small needle bearings the reference speed can exceed the kinematic limit, so the lower of the two governs the application dynamic capacity per millimetre of bore is 0.81 kN/mm and per millimetre of width 0.76 kN/mm — the reason 16 mm-wide needle bearings routinely replace much larger ball or roller positions mass is 21.8 g, just 0.06 g per mm² of projected 23×16 mm envelope, which keeps unbalanced forces low in fast-actuating linkages at 15 mm bore this size balances the 23 mm outside diameter against machineability of the adjacent parts — the most frequently specified band in the HR1 range The hardness requirement is unforgiving: below about 58 HRC the 15 mm journal brinels under the 12.7 kN static rating, and roughness above raceway finish accelerates roller wear NK15/16-XL has no inner ring: the needle rollers run directly on the shaft journal, so the seat must be hardened (58–64 HRC) and ground to bearing raceway quality The -XL suffix marks the X-life execution: refined raceway topography and upgraded materials lift the basic ratings versus the non-X-life bearing at the same 15×23×16 mm envelope. Typical applications include gearbox selector and change linkages, planetary gear bearings and copying and printing machine mechanisms, where the 23 mm outside diameter and 12.1 kN dynamic rating match the duty. In gearbox selector and change linkages the unit fits a compact 15 mm seat, and in planetary gear bearings the 21.8 g mass keeps unbalanced forces low in fast linkages. Designers also specify it for copying and printing machine mechanisms, relying on the 16 mm width and the published 12.7 kN static rating. Needle bearings are pure-radial units — any thrust must be taken by separate washers or an adjacent bearing, especially on flangeless RNAO/NAO. On reciprocating duty ensure the stroke rotates the full needle set, or brinelling occurs at the same roller positions.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• Needle bearings are pure-radial units — any thrust must be taken by separate washers or an adjacent bearing, especially on flangeless RNAO/NAO.
• On reciprocating duty ensure the stroke rotates the full needle set, or brinelling occurs at the same roller positions.
• Without an inner ring the shaft is the raceway: 58–64 HRC and a ground, polished journal are mandatory, not recommendations.