NK26-16 bearing: complete specifications & equivalents

The NK26-16 is a DIN 616 radial bearing sized 26 x 34 x 16 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 = 34 mm d = 26 B = 16 mm side section front view
Principal dimensions: bore d 26 mm, outer diameter D 34 mm, width B 16 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand SKF
Bore diameter d 26 mm
Outer diameter D 34 mm
Width B 16 mm
Material GCr15
Seal / shield open
Internal clearance CN
Tolerance class P0
Cage none
Basic dynamic load rating C 15.7 kN
Basic static load rating C0 26 kN
Fatigue load limit Pu 3.1 kN
Reference speed (thermal) 15000 rpm
Limiting speed (mechanical) 17000 rpm
Operating temperature -40 to +120 °C
Mass 34 g
Manufacturer designation NK 26/16
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 1.024 in
Outer diameter D 1.339 in
Width B 0.63 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) 19 of 46
Bore above smallest NK-series size 21 mm

Cross references & equivalents

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

How the NK26-16 model number is decoded

NK 26/16 is a ribbed machined-ring needle roller bearing (no inner ring) sized 26×34×16 mm: the ground outside diameter seats in the housing, the integral flanges hold the rollers, and the 26 mm shaft journal completes the bearing. The NK 26/16 code states Fw 26 and width 16 mm directly; because the family has no inner ring, the 26 mm journal must be ground, hardened to 58–64 HRC and finished to the raceway tolerance the catalogue specifies. 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. Selection arithmetic: C 15.7 kN against C0 26 kN gives a C0/C ratio of 1.66, and the 3.1 kN fatigue load limit Pu sets the floor for the adjusted-life calculation at contaminated lubrication. Grease through the housing groove before fitting the shaft; the integral flanges hold the grease film at the roller ends, which is where these bearings first starve.

Typical equipment & failure modes

Common applications

  • crank pins and eccentrics where the hardened journal is the raceway
  • gearbox planetary and idler gears on hardened pins
  • piston-pin style pivots in hydraulic pumps
  • guide rollers running on hardened tracks

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
  • electrical erosion on VFD-driven shafts without brush or insulated mounting
  • smearing of rollers and journal during idle periods because the radial section holds too little lubricant

Selection pitfalls — read before you substitute

  • At 26 mm bore, verify shaft deflection against the needle length: these rollers tolerate little edge loading, and a simply supported span between 26 mm seats can bend past the compensation range long before the load rating is exhausted.
  • Hardness is load capacity: in families without an inner ring the 26 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 15.7/26 kN ratings are SKF catalogue values for this exact execution (NK 26/16); ratings can be revised without the order number changing, so keep the catalogue version (SKF catalogue PUB BU/P1 17000) with the drawing.
  • The 15.7/26 kN ratings and 34 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

Can the NK 26/16 run on an unhardened shaft?

No. In this execution the 26 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.

How should the NK 26/16 be mounted?

Press on the ring faces only with a fitting sleeve, keep everything square to the 26 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 NK 26/16?

Beyond the L10 rating, the practical limits are journal/raceway hardness for the 26 mm seat, lubricant condition at the roller ends, and contamination through open ends — the 4.0 mm radial section leaves no reserve once a raceway is dented or ribboned.

What are the dimensions and ratings of the NK 26/16?

A NK 26/16 measures 26 mm bore/Fw × 34 mm outside diameter × 16 mm width (1.024 × 1.339 × 0.63 in). From SKF catalogue PUB BU/P1 17000: radial dynamic rating C 15.7 kN, static C0 26 kN, fatigue limit Pu 3.1 kN, limiting speed 17,000 r/min, reference speed 15,000 r/min, mass about 34 g.

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.