RNAO50X62X20-XL bearing: complete specifications & equivalents

The RNAO50X62X20-XL is a ISO 15 radial bearing sized 50 x 62 x 20 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.

Bearing dimension schematic Front view shows outer diameter D and bore d; side section shows width B. D = 62 mm d = 50 B = 20 mm side section front view
Principal dimensions: bore d 50 mm, outer diameter D 62 mm, width B 20 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand FAG
Bore diameter d 50 mm
Outer diameter D 62 mm
Width B 20 mm
Material GCr15
Seal / shield open
Internal clearance CN
Tolerance class P0
Cage steel
Basic dynamic load rating C 30 kN
Basic static load rating C0 60 kN
Fatigue load limit Pu 9.7 kN
Reference speed (thermal) 5800 rpm
Limiting speed (mechanical) 9300 rpm
Operating temperature -40 to +120 °C
Mass 140 g
Manufacturer designation RNAO50×62×20-XL
Standard ISO 15
Catalog version HR1 2026-09-25
Last verified 2026-09-30

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.

Dimensions in inches & rnao-series range

Bore d 1.969 in
Outer diameter D 2.441 in
Width B 0.787 in
ISO bore code —
Radial section height (D−d)/2 6 mm
Smallest bore in rnao-series 5 mm
Largest outer diameter in rnao-series 120 mm
Width range across rnao-series 8–40 mm
Bore position in rnao-series (smallest first) 18 of 25
Bore above smallest rnao-series size 45 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
RNAO50X62X20 ISO 15 full
Dimensions and internal design equivalent — standard interchange.
ISO 15 boundary-dimension envelope; brand-specific OEM equivalents (NSK/FAG/NTN) pending multi-source data.

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 RNAO50X62X20-XL model number is decoded

envelope 50×62×20 mm: 50 mm seat is the hardened and ground shaft journal itself — there is no inner ring, with a thin 6.0 mm radial section packed with small-diameter needle rollers C is 30 kN and C0 60 kN at the 50 mm seat; the C/C0 ratio of 0.50 is characteristic of a needle bearing — high static rating relative to dynamic in a compact 62 mm outside diameter the fatigue load limit Cur is 9.7 kN, the limiting speed 9,300 r/min and the thermal reference speed 5,800 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 0.60 kN/mm and per millimetre of width 1.50 kN/mm — the reason 20 mm-wide needle bearings routinely replace much larger ball or roller positions mass is 140 g, just 0.11 g per mm² of projected 62×20 mm envelope, which keeps unbalanced forces low in fast-actuating linkages 50 mm bore marks the medium range: mounting forces and fits become critical, and the 140 g mass calls for proper induction or press tooling rather than hand fitting Reading RNAO: O denotes the ribless (open-sided) race design; the single roller row runs directly between ground shaft and housing bore RNAO marks the flangeless needle bearing without inner ring: neither race carries ribs, so the 50 mm hardened shaft journal and the housing faces provide all axial guidance -XL means this is an X-life bearing — Schaeffler's upgraded performance level with smoother raceways, so the 30 kN C rating and longer nominal life come without an envelope change. Typical applications include rocker arms and valve trains, two-stroke and compressor piston pins and small electric motor accessory drives, where the 62 mm outside diameter and 30 kN dynamic rating match the duty. In rocker arms and valve trains the unit fits a compact 50 mm seat, and in two-stroke and compressor piston pins the 140 g mass keeps unbalanced forces low in fast linkages. Designers also specify it for small electric motor accessory drives, relying on the 20 mm width and the published 60 kN static rating. Without an inner ring the shaft is the raceway: 58–64 HRC and a ground, polished journal are mandatory, not recommendations. 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.

Typical equipment & failure modes

Common applications

  • connecting-rod small ends
  • copying and printing machine mechanisms
  • motorcycle and light-vehicle transmissions
  • two-stroke and compressor piston pins

Known failure patterns

  • journal brinelling when a no-inner-ring bearing runs on a shaft hardened below 58 HRC or finished too rough
  • needle skewing and jamming after momentary unloading of a flangeless (RNAO/NAO) pack
  • raceway pitting from contamination drawn through the open ends of an unsealed bearing
  • edge loading at the roller ends from a tapered or lobed shaft seat
  • cage damage from shock loading or from pressing the bearing through the wrong ring
  • lubricant starvation on fast reciprocating strokes that never fully rotate the needles
  • false brinelling during stationary transport vibration
  • spalling from excessive interference that removes the radial clearance
  • roller wear from misaligned connecting-rod eyes and rocker bores

Selection pitfalls — read before you substitute

  • Without an inner ring the shaft is the raceway: 58–64 HRC and a ground, polished journal are mandatory, not recommendations.
  • 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.
  • On reciprocating duty ensure the stroke rotates the full needle set, or brinelling occurs at the same roller positions.

Frequently asked questions

What are the dimensions of the RNAO50×62×20-XL?

The RNAO50×62×20-XL is a RNAO flangeless needle roller bearing without inner ring with 62 mm outside diameter, 50 mm bore and 20 mm width, envelope 50×62×20 mm. Mass is 140 g.

What does the RNAO50×62×20-XL designation mean in the FAG/INA HR1 catalogue?

RNAO50×62×20-XL identifies this RNAO flangeless needle roller bearing without inner ring in the Schaeffler HR1 rolling bearings catalogue; the -XL suffix marks the X-life execution. The envelope is 50×62×20 mm and the catalogue ratings are C 30 kN, C0 60 kN, Cur 9.7 kN.

What is the load capacity of the RNAO50×62×20-XL?

The basic dynamic load rating C is 30 kN and the basic static load rating C0 is 60 kN; the fatigue load limit Cur is 9.7 kN.

What is the maximum speed of the RNAO50×62×20-XL?

The limiting speed is 9,300 r/min and the thermal reference speed is 5,800 r/min. In the Schaeffler catalogue the reference speed is the thermally permissible running speed under defined load; the lower of the two values governs each application.

Can the RNAO50×62×20-XL run directly on an ordinary shaft?

Not on a soft shaft. The RNAO50×62×20-XL has no inner ring, so the 50 mm journal itself is the raceway: harden it to 58–64 HRC and finish-grind to the catalogue journal tolerance. Where the shaft cannot be hardened, use the corresponding with-inner-ring execution instead.

Reviewed & verified by the MPN Base engineering desk against source catalog HR1 2026-09-25 on 2026-09-30. Read our editorial & correction policy.