NKS30-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 NKS30-XL model number is decoded

envelope 30×45×22 mm: 30 mm seat is the hardened and ground shaft journal itself — there is no inner ring, with a thin 7.5 mm radial section packed with small-diameter needle rollers C is 36.5 kN and C0 40 kN at the 30 mm seat; the C/C0 ratio of 0.91 is characteristic of a needle bearing — high static rating relative to dynamic in a compact 45 mm outside diameter the fatigue load limit Cur is 7 kN, the limiting speed 14,000 r/min and the thermal reference speed 8,500 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 1.22 kN/mm and per millimetre of width 1.66 kN/mm — the reason 22 mm-wide needle bearings routinely replace much larger ball or roller positions mass is 104 g, just 0.11 g per mm² of projected 45×22 mm envelope, which keeps unbalanced forces low in fast-actuating linkages with a 30 mm bore the 22 mm width and 36.5 kN C rating suit high-cycle industrial machinery rather than instrument duty The hardness requirement is unforgiving: below about 58 HRC the 30 mm journal brinels under the 40 kN static rating, and roughness above raceway finish accelerates roller wear This bearing accepts axial displacement between shaft and housing because the rollers rotate on the free journal; it locates nothing axially and must be flanked by guide faces X-life status (-XL) indicates the current Schaeffler premium execution at 30 mm bore; the 40 kN C0 rating reflects the improved rolling-contact geometry. Typical applications include hydraulic and pneumatic pump eccentrics, copying and printing machine mechanisms and agricultural machine pivots and linkages, where the 45 mm outside diameter and 36.5 kN dynamic rating match the duty. In hydraulic and pneumatic pump eccentrics the unit fits a compact 30 mm seat, and in copying and printing machine mechanisms the 104 g mass keeps unbalanced forces low in fast linkages. Designers also specify it for agricultural machine pivots and linkages, relying on the 22 mm width and the published 40 kN static rating. Open ends draw contamination directly onto the needles; specify sealed or shielded positions in dusty environments rather than relying on grease alone. 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

• Open ends draw contamination directly onto the needles; specify sealed or shielded positions in dusty environments rather than relying on grease alone.
• On reciprocating duty ensure the stroke rotates the full needle set, or brinelling occurs at the same roller positions.
• 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.