NKI6-16-TN bearing: complete specifications & equivalents

The NKI6-16-TN is a DIN 616 radial bearing sized 6 x 16 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 = 16 mm d = 6 B = 16 mm side section front view
Principal dimensions: bore d 6 mm, outer diameter D 16 mm, width B 16 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand SKF
Bore diameter d 6 mm
Outer diameter D 16 mm
Width B 16 mm
Material GCr15
Seal / shield open
Internal clearance CN
Tolerance class P0
Cage polymer (PA66 glass-fibre reinforced)
Basic dynamic load rating C 5.72 kN
Basic static load rating C0 7.2 kN
Fatigue load limit Pu 0.815 kN
Reference speed (thermal) 30000 rpm
Limiting speed (mechanical) 34000 rpm
Operating temperature -40 to +120 °C
Mass 17 g
Manufacturer designation NKI 6/16 TN
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 0.236 in
Outer diameter D 0.63 in
Width B 0.63 in
ISO bore code —
Radial section height (D−d)/2 5 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) 2 of 30
Bore above smallest NKI-series size 1 mm

Cross references & equivalents

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

How the NKI6-16-TN model number is decoded

NKI 6/16 TN is a machined-ring needle roller bearing with an inner ring: flanged outer ring plus a separate 6 mm bore inner ring, so the shaft seat needs only ordinary tolerance, as tabulated by SKF in SKF catalogue PUB BU/P1 17000. In SKF nomenclature the leading letters mark a machined-ring needle bearing with inner ring: figures state 6 mm d and 16 mm B, the 16 mm outside diameter from the machined-ring needle roller bearings with inner ring, and the 2RS suffix would add contact seals. 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 17 g catalogue mass and 5.0 mm radial section ((16−6)/2) frame a rating of about 0.95 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

  • needle edge loading and raceway denting when the shaft deflects beyond the compensation range
  • polymer cage deformation when the local temperature exceeds the 120 °C sustained limit
  • abrasive paste formation from dust ingressing past open ends without effective housing seals
  • hard-particle indentation in unfiltered lubricant
  • inner-ring bore fretting on a loose shaft seat, migrating hard particles into the rolling contact

Selection pitfalls — read before you substitute

  • At Fw 6 mm the rolling elements are under two millimetres long — handle the NKI 6/16 TN like a watch part: one dropped assembly, one over-pressed cup or one coarse journal finish outweighs any catalogue rating difference.
  • The quoted 5.72/7.2 kN ratings are SKF catalogue values for this exact execution (NKI 6/16 TN); ratings can be revised without the order number changing, so keep the catalogue version (SKF catalogue PUB BU/P1 17000) with the drawing.
  • Oscillating pivots fail differently: rocking through a small angle concentrates wear in the same roller positions — inspect those zones, and consider rotating the assembly's clock position at service intervals.
  • The 5.72/7.2 kN ratings and 17 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

Which dimensions does the NKI 6/16 TN have?

A NKI 6/16 TN measures 6 mm bore/Fw × 16 mm outside diameter × 16 mm width (0.236 × 0.63 × 0.63 in). From SKF catalogue PUB BU/P1 17000: radial dynamic rating C 5.72 kN, static C0 7.2 kN, fatigue limit Pu 0.815 kN, limiting speed 34,000 r/min, reference speed 30,000 r/min, mass about 17 g.

What does NKI 6/16 TN mean in SKF part numbering?

The letters mark a machined-ring needle roller bearing with inner ring: 6 mm bore, 16 mm width, 16 mm OD per the series plan. The hardened inner ring is the raceway, so an ordinary k5 shaft seat suffices.

Does the NKI 6/16 TN need a hardened and ground shaft?

Yes — that is the point of this family. The NKI 6/16 TN carries its own hardened, ground inner ring on a 6 mm seat, so the shaft needs only a normal k5/j6 finish. The inner ring is separable and replaceable.

What mounting mistakes ruin a NKI 6/16 TN?

Mount the inner ring on the 6 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.