NKIS17-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 NKIS17-XL model number is decoded

envelope 17×37×20 mm: 17 mm bore accepts a normal-tolerance machined shaft via the integral inner ring, with a thin 10.0 mm radial section packed with small-diameter needle rollers C is 29.5 kN and C0 31 kN at the 17 mm seat; the C/C0 ratio of 0.95 is characteristic of a needle bearing — high static rating relative to dynamic in a compact 37 mm outside diameter the fatigue load limit Cur is 5.5 kN, the limiting speed 17,200 r/min and the thermal reference speed 8,800 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 1.74 kN/mm and per millimetre of width 1.48 kN/mm — the reason 20 mm-wide needle bearings routinely replace much larger ball or roller positions mass is 98 g, just 0.13 g per mm² of projected 37×20 mm envelope, which keeps unbalanced forces low in fast-actuating linkages with a 17 mm bore the 20 mm width and 29.5 kN C rating suit high-cycle industrial machinery rather than instrument duty Reading the NKIS prefix: machined-ring needle bearing with inner ring, one roller row, capable of pure radial load at 29.5 kN C Cur 5.5 kN, limiting speed 17,200 r/min, reference speed 8,800 r/min — the inner ring adds a few grams (total 98 g) but removes the hardening requirement The -XL suffix is the Schaeffler X-life mark: interchangeable envelope with the basic bearing, but higher load capacity and lower running temperature at the 17,200 r/min limit. Typical applications include agricultural machine pivots and linkages, hydraulic and pneumatic pump eccentrics and textile machine heald and cam shafts, where the 37 mm outside diameter and 29.5 kN dynamic rating match the duty. In agricultural machine pivots and linkages the unit fits a compact 17 mm seat, and in hydraulic and pneumatic pump eccentrics the 98 g mass keeps unbalanced forces low in fast linkages. Designers also specify it for textile machine heald and cam shafts, relying on the 20 mm width and the published 31 kN static rating. Adding an IR inner ring changes the envelope logic: the same outer assembly then fits a smaller shaft — recheck bore, clearance and ratings when substituting. Keep the specified radial clearance; an oversized shaft or heavy interference removes it and the needles bind hot immediately.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• Adding an IR inner ring changes the envelope logic: the same outer assembly then fits a smaller shaft — recheck bore, clearance and ratings when substituting.
• Keep the specified radial clearance; an oversized shaft or heavy interference removes it and the needles bind hot immediately.
• Do not press an RNA/NK assembly in through the outer ring when mounting it on a shaft, and vice versa — rolling forces through the wrong ring bruises the raceways.