NK20-16-D-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 NK20-16-D-XL model number is decoded

envelope 20×28×16 mm: 20 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 18.5 kN and C0 23.9 kN at the 20 mm seat; the C/C0 ratio of 0.77 is characteristic of a needle bearing — high static rating relative to dynamic in a compact 28 mm outside diameter the fatigue load limit Cur is 4.1 kN, the limiting speed 21,100 r/min and the thermal reference speed 12,100 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 0.93 kN/mm and per millimetre of width 1.16 kN/mm — the reason 16 mm-wide needle bearings routinely replace much larger ball or roller positions mass is 28.4 g, just 0.06 g per mm² of projected 28×16 mm envelope, which keeps unbalanced forces low in fast-actuating linkages the 20 mm bore falls in the small band, the workhorse size for gearbox planetary positions, hydraulic pumps and general cam and linkage duty Omitting the inner ring frees radial space — at a 20 mm shaft the outer diameter is only 28 mm and the width 16 mm, yet C is 18.5 kN With Cur 4.1 kN and a 21,100 r/min limiting speed the unit suits pivots, rocker arms, pumps and compact gear trains running on hardened pins 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 21,100 r/min limit. The split -D cage targets positions where the shaft cannot be threaded through an intact bearing; seating and axial retention must follow the mounting instructions. Typical applications include textile machine heald and cam shafts, agricultural machine pivots and linkages and connecting-rod small ends, where the 28 mm outside diameter and 18.5 kN dynamic rating match the duty. In textile machine heald and cam shafts the unit fits a compact 20 mm seat, and in agricultural machine pivots and linkages the 28.4 g mass keeps unbalanced forces low in fast linkages. Designers also specify it for connecting-rod small ends, relying on the 16 mm width and the published 23.9 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. Open ends draw contamination directly onto the needles; specify sealed or shielded positions in dusty environments rather than relying on grease alone.

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.
• Open ends draw contamination directly onto the needles; specify sealed or shielded positions in dusty environments rather than relying on grease alone.
• 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.