RNA4915-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 RNA4915-XL model number is decoded

envelope 85×105×30 mm: 85 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 97 kN and C0 162 kN at the 85 mm seat; the C/C0 ratio of 0.60 is characteristic of a needle bearing — high static rating relative to dynamic in a compact 105 mm outside diameter the fatigue load limit Cur is 29 kN, the limiting speed 5,400 r/min and the thermal reference speed 3,200 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 1.14 kN/mm and per millimetre of width 3.23 kN/mm — the reason 30 mm-wide needle bearings routinely replace much larger ball or roller positions mass is 489 g, just 0.16 g per mm² of projected 105×30 mm envelope, which keeps unbalanced forces low in fast-actuating linkages the 85 mm bore belongs to the large band, where HR1 full-complement and track-roller designs deliver their highest kilonewton ratings in slow, heavily loaded machinery Reading the RNA49 prefix: a machined (not drawn-cup) outer ring with the needle complement; an inner ring from the IR series can be added later if the shaft cannot be hardened The hardness requirement is unforgiving: below about 58 HRC the 85 mm journal brinels under the 162 kN static rating, and roughness above raceway finish accelerates roller wear The -XL suffix marks the X-life execution: refined raceway topography and upgraded materials lift the basic ratings versus the non-X-life bearing at the same 85×105×30 mm envelope. Typical applications include rocker arms and valve trains, two-stroke and compressor piston pins and small electric motor accessory drives, where the 105 mm outside diameter and 97 kN dynamic rating match the duty. In rocker arms and valve trains the unit fits a compact 85 mm seat, and in two-stroke and compressor piston pins the 489 g mass keeps unbalanced forces low in fast linkages. Designers also specify it for small electric motor accessory drives, relying on the 30 mm width and the published 162 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. 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

• Open ends draw contamination directly onto the needles; specify sealed or shielded positions in dusty environments rather than relying on grease alone.
• Keep the specified radial clearance; an oversized shaft or heavy interference removes it and the needles bind hot immediately.
• On reciprocating duty ensure the stroke rotates the full needle set, or brinelling occurs at the same roller positions.