NKI15-16 bearing: complete specifications & equivalents

The NKI15-16 is a DIN 616 radial bearing sized 15 x 27 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 = 27 mm d = 15 B = 16 mm side section front view
Principal dimensions: bore d 15 mm, outer diameter D 27 mm, width B 16 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand SKF
Bore diameter d 15 mm
Outer diameter D 27 mm
Width B 16 mm
Material GCr15
Seal / shield open
Internal clearance CN
Tolerance class P0
Cage none
Basic dynamic load rating C 13.4 kN
Basic static load rating C0 19 kN
Fatigue load limit Pu 2.28 kN
Reference speed (thermal) 20000 rpm
Limiting speed (mechanical) 24000 rpm
Operating temperature -40 to +120 °C
Mass 39 g
Manufacturer designation NKI 15/16
Standard DIN 616
Catalog version SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 7.4 machined rings with flanges, with an inner ring
Last verified 2026-09-26

Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 7.4 machined rings with flanges, with 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. 7.4 machined rings with flanges, with 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 & NKI-series range

Bore d 0.591 in
Outer diameter D 1.063 in
Width B 0.63 in
ISO bore code —
Radial section height (D−d)/2 6 mm
Smallest bore in NKI-series 5 mm
Largest outer diameter in NKI-series 130 mm
Width range across NKI-series 12–40 mm
Bore position in NKI-series (smallest first) 7 of 30
Bore above smallest NKI-series size 10 mm

Cross references & equivalents

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

How the NKI15-16 model number is decoded

NKI 15/16 provides the full machined-ring needle roller construction: ground inner ring on a 15 mm seat, flanged outer ring at 27 mm, caged needles between them — the standard choice when a replaceable inner raceway is required. The NKI 15/16 code gives bore 15 mm and width 16 mm explicitly; unlike the RNA/NK families the shaft only needs a standard k5/j5 seat because the hardened inner ring is the raceway. The 2RS executions of the 49 series carry contact seals on both faces and a wider outer ring — their B and s dimensions differ from the open execution, so housings must be re-checked before substituting. The 39 g catalogue mass and 6.0 mm radial section ((27−15)/2) frame a rating of about 0.89 kN dynamic per millimetre of bore — the needle construction's density advantage over ball bearings of the same envelope. For NA 49 2RS executions the wider outer ring changes the housing depth: verify the 16 mm width and s offset dimensions against the open execution before reusing an existing bore.

Typical equipment & failure modes

Common applications

  • conveyor roller ends and return rollers
  • agricultural implement pivots and cutter heads
  • electric motor armature shafts with ground seats
  • printing and paper-handling rollers

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
  • inner-ring raceway spalling after the narrow ring section runs hot with excessive interference

Selection pitfalls — read before you substitute

  • On a 15 mm seat the housing bore quality dominates life: a bore 0.02 mm out of round pinches the 27 mm ring or cup into a lobed shape, and the rollers then trace the housing's geometry error, not the design load.
  • Do not interchange envelope-identical needle families blindly: NKI 15/16 shares its 15×27×16 mm outline with inner-ring and sealed siblings whose ratings differ — the family letters are part of the specification, not decoration.
  • Reference and limiting speeds are different limits: the 20,000 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.
  • The 13.4/19 kN ratings and 39 g mass are SKF catalogue values transcribed from ch. 7.4 of PUB BU/P1 17000 (PDF table page 638); combined-type axial ratings appear in the text above because the structured record carries radial values only.

Frequently asked questions

What are the dimensions and ratings of the NKI 15/16?

A NKI 15/16 measures 15 mm bore/Fw × 27 mm outside diameter × 16 mm width (0.591 × 1.063 × 0.63 in). From SKF catalogue PUB BU/P1 17000: radial dynamic rating C 13.4 kN, static C0 19 kN, fatigue limit Pu 2.28 kN, limiting speed 24,000 r/min, reference speed 20,000 r/min, mass about 39 g.

How is the NKI 15/16 designation read?

The letters mark a machined-ring needle roller bearing with inner ring: 15 mm bore, 16 mm width, 27 mm OD per the series plan. The hardened inner ring is the raceway, so an ordinary k5 shaft seat suffices.

Can the NKI 15/16 run on an unhardened shaft?

Yes — that is the point of this family. The NKI 15/16 carries its own hardened, ground inner ring on a 15 mm seat, so the shaft needs only a normal k5/j6 finish. The inner ring is separable and replaceable.

How should the NKI 15/16 be mounted?

Mount the inner ring on the 15 mm seat first (induction heat, max 120 °C, or press), then fit the flanged outer ring into the H7 housing bore. Verify free rotation and, for 2RS executions, check the wider outer ring against the housing depth.

Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 7.4 machined rings with flanges, with an inner ring on 2026-09-26. Read our editorial & correction policy.