NKS70-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 NKS70-XL model number is decoded

envelope 70×90×28 mm: 70 mm seat is the hardened and ground shaft journal itself — there is no inner ring, with a thin 10.0 mm radial section packed with small-diameter needle rollers C is 77 kN and C0 113 kN at the 70 mm seat; the C/C0 ratio of 0.68 is characteristic of a needle bearing — high static rating relative to dynamic in a compact 90 mm outside diameter the fatigue load limit Cur is 20.4 kN, the limiting speed 6,400 r/min and the thermal reference speed 4,200 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 1.10 kN/mm and per millimetre of width 2.75 kN/mm — the reason 28 mm-wide needle bearings routinely replace much larger ball or roller positions mass is 380 g, just 0.15 g per mm² of projected 90×28 mm envelope, which keeps unbalanced forces low in fast-actuating linkages with a 70 mm bore this is a heavy-industrial bearing: 380 g of stiff ring and roller set, specified where rigidity matters more than speed Omitting the inner ring frees radial space — at a 70 mm shaft the outer diameter is only 90 mm and the width 28 mm, yet C is 77 kN NKS70-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 -XL means this is an X-life bearing — Schaeffler's upgraded performance level with smoother raceways, so the 77 kN C rating and longer nominal life come without an envelope change. Typical applications include agricultural machine pivots and linkages, hydraulic and pneumatic pump eccentrics and textile machine heald and cam shafts, where the 90 mm outside diameter and 77 kN dynamic rating match the duty. In agricultural machine pivots and linkages the unit fits a compact 70 mm seat, and in hydraulic and pneumatic pump eccentrics the 380 g mass keeps unbalanced forces low in fast linkages. Designers also specify it for textile machine heald and cam shafts, relying on the 28 mm width and the published 113 kN static rating. On reciprocating duty ensure the stroke rotates the full needle set, or brinelling occurs at the same roller positions. Needle bearings are pure-radial units — any thrust must be taken by separate washers or an adjacent bearing, especially on flangeless RNAO/NAO.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

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