NKI85-26 bearing: complete specifications & equivalents
The NKI85-26 is a DIN 616 radial bearing sized 85 x 115 x 26 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 85 mm |
| Outer diameter D | 115 mm |
| Width B | 26 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | none |
| Basic dynamic load rating C | 73.7 kN |
| Basic static load rating C0 | 146 kN |
| Fatigue load limit Pu | 18.6 kN |
| Reference speed (thermal) | 4300 rpm |
| Limiting speed (mechanical) | 4800 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 740 g |
| Manufacturer designation | NKI 85/26 |
| 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 | 3.346 in |
|---|---|
| Outer diameter D | 4.528 in |
| Width B | 1.024 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 15 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) | 27 of 30 |
| Bore above smallest NKI-series size | 80 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the NKI85-26 model number is decoded
SKF lists NKI 85/26 in the machined-ring needle roller bearings with inner ring with boundary dimensions 85×115×26 mm: an inner ring turns on the shaft while the flanged outer ring carries the needle roller complement in the housing. In SKF nomenclature the leading letters mark a machined-ring needle bearing with inner ring: figures state 85 mm d and 26 mm B, the 115 mm outside diameter from the machined-ring needle roller bearings with inner ring, and the 2RS suffix would add contact seals. TN polymer cage executions run quieter and tolerate grease-lubricated pivot duty; steel cage executions remain the choice for higher temperature or oil-bath lubrication. The 740 g catalogue mass and 15.0 mm radial section ((115−85)/2) frame a rating of about 0.87 kN dynamic per millimetre of bore — the needle construction's density advantage over ball bearings of the same envelope. Because the inner ring is separable, mount it first against its shoulder, then slide the outer ring and roller set over it — the order avoids forcing rollers across the shaft threads or burrs.
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
- brinelling of raceways from impact or pressing force transmitted through the rolling elements
- inner-ring bore fretting on a loose shaft seat, migrating hard particles into the rolling contact
Selection pitfalls — read before you substitute
- Above 50 mm bore, thermal growth matters: the 85 mm inner ring or journal grows with temperature faster than the housing, and the small clearance of a needle roller contact leaves little reserve — check running clearance hot, not just at assembly.
- The quoted 73.7/146 kN ratings are SKF catalogue values for this exact execution (NKI 85/26); 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 73.7/146 kN ratings and 740 g mass are SKF catalogue values transcribed from ch. 7.4 of PUB BU/P1 17000 (PDF table page 644); combined-type axial ratings appear in the text above because the structured record carries radial values only.
Frequently asked questions
What mounting mistakes ruin a NKI 85/26?
Mount the inner ring on the 85 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.
Is the NKI 85/26 sealed?
No — the open execution relies on housing seals; 2RS executions of the 49 series add contact seals with a wider outer ring as a separate order number.
Which dimensions does the NKI 85/26 have?
A NKI 85/26 measures 85 mm bore/Fw × 115 mm outside diameter × 26 mm width (3.346 × 4.528 × 1.024 in). From SKF catalogue PUB BU/P1 17000: radial dynamic rating C 73.7 kN, static C0 146 kN, fatigue limit Pu 18.6 kN, limiting speed 4,800 r/min, reference speed 4,300 r/min, mass about 740 g.
What does NKI 85/26 mean in SKF part numbering?
The letters mark a machined-ring needle roller bearing with inner ring: 85 mm bore, 26 mm width, 115 mm OD per the series plan. The hardened inner ring is the raceway, so an ordinary k5 shaft seat suffices.
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.