NK14-20 bearing: complete specifications & equivalents

The NK14-20 is a DIN 616 radial bearing sized 14 x 22 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 = 22 mm d = 14 B = 20 mm side section front view
Principal dimensions: bore d 14 mm, outer diameter D 22 mm, width B 20 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand SKF
Bore diameter d 14 mm
Outer diameter D 22 mm
Width B 20 mm
Material GCr15
Seal / shield open
Internal clearance CN
Tolerance class P0
Cage none
Basic dynamic load rating C 12.8 kN
Basic static load rating C0 16.6 kN
Fatigue load limit Pu 2 kN
Reference speed (thermal) 24000 rpm
Limiting speed (mechanical) 28000 rpm
Operating temperature -40 to +120 °C
Mass 26 g
Manufacturer designation NK 14/20
Standard DIN 616
Catalog version SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 7.3 machined rings with flanges, without an inner ring
Last verified 2026-09-26

Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 7.3 machined rings with flanges, without an inner ring) · extracted 2026-09-26

Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 7.3 machined rings with flanges, without an inner ring); SKF® and SKF Explorer® are trademarks of AB SKF, used here for identification only — mpnbase is not an authorized SKF distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at skf.com.

Dimensions in inches & NK-series range

Bore d 0.551 in
Outer diameter D 0.866 in
Width B 0.787 in
ISO bore code —
Radial section height (D−d)/2 4 mm
Smallest bore in NK-series 5 mm
Largest outer diameter in NK-series 130 mm
Width range across NK-series 10–40 mm
Bore position in NK-series (smallest first) 8 of 46
Bore above smallest NK-series size 9 mm

Cross references & equivalents

No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.

How the NK14-20 model number is decoded

NK 14/20 is a ribbed machined-ring needle roller bearing (no inner ring) sized 14×22×20 mm: the ground outside diameter seats in the housing, the integral flanges hold the rollers, and the 14 mm shaft journal completes the bearing. Reading the designation: NK gives the series and the numbers the boundary plan — 14 mm Fw for the shaft seat, 20 mm width; the 22 mm OD comes from the dimension series, and the absence of an inner ring is built into the family name. The wide NKS/NKIS siblings share the Fw and OD but add width for higher ratings — check both when the radial space allows a wider seat. For life calculation, the 12.8/16.6 kN ratings assume raceway geometry supplied by the shaft and housing in families without an inner ring — journal hardness, roundness and finish are part of the bearing, not of the application. Mounting: the flanged outer ring presses into the H7 housing bore against its flange face; the shaft (hardened to 58–64 HRC, ground) enters afterwards, and axial retention is by the housing wall plus a cover washer.

Typical equipment & failure modes

Common applications

  • guide rollers running on hardened tracks
  • swing arms and lever pivots with oscillating duty
  • cam followers built up from separate components
  • crank pins and eccentrics where the hardened journal is the raceway

Known failure patterns

  • needle edge loading and raceway denting when the shaft deflects beyond the compensation range
  • cage pocket wear and roller skew after sustained operation with too little radial preload
  • abrasive paste formation from dust ingressing past open ends without effective housing seals
  • rolling-contact fatigue spalling after the rated L10 life
  • smearing of rollers and journal during idle periods because the radial section holds too little lubricant

Selection pitfalls — read before you substitute

  • On a 14 mm seat the housing bore quality dominates life: a bore 0.02 mm out of round pinches the 22 mm ring or cup into a lobed shape, and the rollers then trace the housing's geometry error, not the design load.
  • Reference and limiting speeds are different limits: the 24,000 r/min reference is the thermal criterion under load, The limiting value is mechanical; the reference value is thermal under load, and grease choice moves it substantially.
  • Hardness is load capacity: in families without an inner ring the 14 mm journal must hold 58–64 HRC with a ground finish; a surface that looks fine but sits at 45 HRC will rib the raceway within weeks.
  • The 12.8/16.6 kN ratings and 26 g mass are SKF catalogue values transcribed from ch. 7.3 of PUB BU/P1 17000 (PDF table page 626); combined-type axial ratings appear in the text above because the structured record carries radial values only.

Frequently asked questions

Is the NK 14/20 sealed?

No — this execution is open and depends on the housing sealing arrangement; grease it at assembly and keep the relubrication interval short in dirty duty.

Which dimensions does the NK 14/20 have?

A NK 14/20 measures 14 mm bore/Fw × 22 mm outside diameter × 20 mm width (0.551 × 0.866 × 0.787 in). From SKF catalogue PUB BU/P1 17000: radial dynamic rating C 12.8 kN, static C0 16.6 kN, fatigue limit Pu 2 kN, limiting speed 28,000 r/min, reference speed 24,000 r/min, mass about 26 g.

What does NK 14/20 mean in SKF part numbering?

NK names a machined-ring needle roller bearing without inner ring: the figures give Fw 14 mm and width 20 mm, OD 22 mm comes from the dimension series, and the flanged outer ring retains the caged rollers.

Does the NK 14/20 need a hardened and ground shaft?

No. In this execution the 14 mm shaft journal is the inner raceway: it must be ground and hardened to 58–64 HRC (with matching housing bore quality on the outside). If the shaft cannot meet that, order the inner-ring sibling (NKI/NA execution) plus its ground inner ring instead.

Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 7.3 machined rings with flanges, without an inner ring on 2026-09-26. Read our editorial & correction policy.