NA4838-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 NA4838-XL model number is decoded

envelope 190×240×50 mm: 190 mm bore accepts a normal-tolerance machined shaft via the integral inner ring, with a thin 25.0 mm radial section packed with small-diameter needle rollers C is 255 kN and C0 690 kN at the 190 mm seat; the C/C0 ratio of 0.37 is characteristic of a needle bearing — high static rating relative to dynamic in a compact 240 mm outside diameter the fatigue load limit Cur is 102 kN, the limiting speed 2,250 r/min and the thermal reference speed 1,330 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 1.34 kN/mm and per millimetre of width 5.10 kN/mm — the reason 50 mm-wide needle bearings routinely replace much larger ball or roller positions mass is 5.61 kg (5610 g), just 0.47 g per mm² of projected 240×50 mm envelope, which keeps unbalanced forces low in fast-actuating linkages the 190 mm bore puts this execution at the top of the HR1 range — the 240 mm outside diameter, 50 mm width and 5.61 kg mass are built for primary-industry load cases This is the choice for OEM production on soft shafts: machine the 190 mm seat to the recommended tolerance, fit the bearing, and let the inner ring provide the precision raceway X-life status (-XL) indicates the current Schaeffler premium execution at 190 mm bore; the 690 kN C0 rating reflects the improved rolling-contact geometry. Typical applications include planetary gear bearings, small electric motor accessory drives and gearbox selector and change linkages, where the 240 mm outside diameter and 255 kN dynamic rating match the duty. In planetary gear bearings the unit fits a compact 190 mm seat, and in small electric motor accessory drives the 5.61 kg mass is part of the rotor inertia calculation. Designers also specify it for gearbox selector and change linkages, relying on the 50 mm width and the published 690 kN static rating. 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. 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

• 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.
• Open ends draw contamination directly onto the needles; specify sealed or shielded positions in dusty environments rather than relying on grease alone.
• Needle bearings are pure-radial units — any thrust must be taken by separate washers or an adjacent bearing, especially on flangeless RNAO/NAO.