NKS24 bearing: complete specifications & equivalents
The NKS24 is a DIN 616 radial bearing sized 24 x 37 x 20 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 24 mm |
| Outer diameter D | 37 mm |
| Width B | 20 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | none |
| Basic dynamic load rating C | 26 kN |
| Basic static load rating C0 | 33.5 kN |
| Fatigue load limit Pu | 4 kN |
| Reference speed (thermal) | 15000 rpm |
| Limiting speed (mechanical) | 17000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 66 g |
| Manufacturer designation | NKS 24 |
| 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 & NKS-series range
| Bore d | 0.945 in |
|---|---|
| Outer diameter D | 1.457 in |
| Width B | 0.787 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 6.5 mm |
| Smallest bore in NKS-series | 20 mm |
| Largest outer diameter in NKS-series | 95 mm |
| Width range across NKS-series | 20–28 mm |
| Bore position in NKS-series (smallest first) | 2 of 17 |
| Bore above smallest NKS-series size | 4 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the NKS24 model number is decoded
SKF's wide-section machined-ring needle roller bearings without inner ring include NKS 24: 24 mm Fw, 37 mm outside diameter, 20 mm width — a machined and ground outer ring whose rolled flanges retain the needle rollers, running on the shaft as the inner raceway. The NKS 24 code states Fw 24 and width 20 mm directly; because the family has no inner ring, the 24 mm journal must be ground, hardened to 58–64 HRC and finished to the raceway tolerance the catalogue specifies. The machined ring is through-hardened and ground on OD, bore-side raceway and faces; the flanged lip design means the housing shoulder can be omitted — the ring clamps axially between housing wall and cover washer. Minimum load matters: below roughly 0.02·C the rollers skid and smear; preloading the pivot or specifying a heavier execution avoids the glazing that pure oscillation produces on these raceways. Fit the outer ring with a press and a fitting sleeve, not by hammering the flanges — rolled flanges chip; the 37 mm ground OD takes the press fit that prevents outer-ring creep in oscillating duty.
Typical equipment & failure modes
Common applications
- 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
- gearbox planetary and idler gears on hardened pins
Known failure patterns
- raceway spalling once the catalogue L10 life is exceeded or after overload events
- 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
- false brinelling of standby equipment under external vibration
- smearing of rollers and journal during idle periods because the radial section holds too little lubricant
Selection pitfalls — read before you substitute
- On a 24 mm seat the housing bore quality dominates life: a bore 0.02 mm out of round pinches the 37 mm ring or cup into a lobed shape, and the rollers then trace the housing's geometry error, not the design load.
- Hardness is load capacity: in families without an inner ring the 24 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 quoted 26/33.5 kN ratings are SKF catalogue values for this exact execution (NKS 24); ratings can be revised without the order number changing, so keep the catalogue version (SKF catalogue PUB BU/P1 17000) with the drawing.
- The 26/33.5 kN ratings and 66 g mass are SKF catalogue values transcribed from ch. 7.3 of PUB BU/P1 17000 (PDF table page 628); combined-type axial ratings appear in the text above because the structured record carries radial values only.
Frequently asked questions
How should the NKS 24 be mounted?
Press on the ring faces only with a fitting sleeve, keep everything square to the 24 mm seat, and never transmit force through the rolling elements. Follow the catalogue's seat tolerances — the narrow needle contact forgives neither tilt nor burrs.
What limits the service life of a NKS 24?
Beyond the L10 rating, the practical limits are journal/raceway hardness for the 24 mm seat, lubricant condition at the roller ends, and contamination through open ends — the 6.5 mm radial section leaves no reserve once a raceway is dented or ribboned.
What are the dimensions and ratings of the NKS 24?
A NKS 24 measures 24 mm bore/Fw × 37 mm outside diameter × 20 mm width (0.945 × 1.457 × 0.787 in). From SKF catalogue PUB BU/P1 17000: radial dynamic rating C 26 kN, static C0 33.5 kN, fatigue limit Pu 4 kN, limiting speed 17,000 r/min, reference speed 15,000 r/min, mass about 66 g.
How is the NKS 24 designation read?
NKS names a machined-ring needle roller bearing without inner ring: the figures give Fw 24 mm and width 20 mm, OD 37 mm comes from the dimension series, and the flanged outer ring retains the caged rollers.
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.