61917 bearing: complete specifications & equivalents
The 61917 is a ISO 15 radial bearing sized 85 x 120 x 18 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 | 120 mm |
| Width B | 18 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN / C3 available |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 31.9 kN |
| Basic static load rating C0 | 30 kN |
| Fatigue load limit Pu | 1.25 kN |
| Reference speed (thermal) | 11000 rpm |
| Limiting speed (mechanical) | 7000 rpm |
| Operating temperature | -40 to +150 °C |
| Mass | 550 g |
| Manufacturer designation | SKF 61917 |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018) |
| Last verified | 2026-09-24 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018)) · extracted 2026-09-24
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018)); 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 & 61900-series range
| Bore d | 3.346 in |
|---|---|
| Outer diameter D | 4.724 in |
| Width B | 0.709 in |
| ISO bore code | 17 |
| Radial section height (D−d)/2 | 17.5 mm |
| Smallest bore in 61900-series | 3 mm |
| Largest outer diameter in 61900-series | 1120 mm |
| Width range across 61900-series | 3–118 mm |
| Bore position in 61900-series (smallest first) | 25 of 63 |
| Bore above smallest 61900-series size | 82 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 61917-2RS | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 85×120×18 mm envelope per ISO 15; seal variant differs (OPEN vs 2RS) — confirm sealing suits the duty. |
| 61917-NSK | NSK | full Dimensions and internal design equivalent — standard interchange. | Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier. |
| 61917-RSR | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 85×120×18 mm envelope per ISO 15; seal variant differs (OPEN vs RSR) — confirm sealing suits the duty. |
| 61917-ZZ | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 85×120×18 mm envelope per ISO 15; seal variant differs (OPEN vs ZZ) — confirm sealing suits the duty. |
| 61917-2RS-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 85×120×18 mm envelope per ISO 15; seal variant (OPEN vs 2RS) and load ratings differ — confirm sealing and rating before substituting. |
| 61917-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 85×120×18 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
| 61917-RSR-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 85×120×18 mm envelope per ISO 15; seal variant (OPEN vs RSR) and load ratings differ — confirm sealing and rating before substituting. |
| 61917-ZZ-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 85×120×18 mm envelope per ISO 15; seal variant (OPEN vs ZZ) and load ratings differ — confirm sealing and rating before substituting. |
Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.
How the 61917 model number is decoded
61917 is supplied open, without shields or seals, so the arrangement around it must supply and retain the lubricant. Within the thin 619xx section (diameter series 9 of ISO 15), multiplying bore code 17 by five gives the 85 mm bore; the 120 mm outside diameter and 18 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 85 mm shaft under normal load, catalogue practice seats it on a k5 shaft fit with an H7 housing bore — confirm against the actual load direction and magnitude before committing. In the SKF catalogue this open execution carries the bare designation; protected variants are ordered separately as -2Z and -2RSH.
Typical equipment & failure modes
Common applications
- lay shafts and idler shafts
- textile machinery
- packaging machinery
- space-constrained gearboxes
Known failure patterns
- contamination wear from dust and dirt ingress through the open arrangement
- lubricant starvation when no regreasing interval is maintained
- brinelling from static overload or hammering during mounting
- false brinelling from vibration while the shaft is stationary
Selection pitfalls — read before you substitute
- Mount this 85 mm bore bearing by heating the inner ring (induction heater, max 120 °C) — never drive it home through the outer ring or balls, that brinells the raceways.
- The 619xx thin section (17.5 mm section height at 85 mm bore) trades load capacity for compactness; stiff, accurately aligned seats are essential or edge loading will spall the raceway early.
- The open 61917 has no lubricant retention: grease escapes and contaminants migrate straight into the 85×120×18 mm raceway, so specify a sealed arrangement for dusty or washdown duty.
- Open bearings tolerate the highest speeds in the 61900-series but need a defined regreasing interval; run-to-failure lubrication is the dominant cause of early failure in open 61917 units.
- Axial location must clamp the ring face, not the seal area: a shoulder or circlip bearing on the seal side of the 18 mm-wide ring of 61917 drags the lip and overheats it.
- Do not quieten a noisy bearing by preloading it: the 61900-series is a deep-groove design, not angular-contact; axial preload raises temperature and shortens grease life.
- The open 61917 needs external sealing and application-supplied lubrication; in the SKF catalogue the protected variants are separate order numbers 61917-2Z (shields) and 61917-2RSH (contact seals), not suffix-free 61917.
- The 31.9/30 kN ratings here are SKF Explorer-class figures from catalogue PUB BU/P1 17000/1 EN (Oct 2018); SKF can revise internal geometry and ratings without changing the designation, so treat the catalogue version and date as part of the specification and re-verify for critical drives.
Frequently asked questions
What are the dimensions of a 61917 bearing?
A 61917 deep-groove ball bearing has a 85 mm bore, 120 mm outer diameter and 18 mm width (3.346 × 4.724 × 0.709 in), per ISO 15 boundary dimensions. It is an open bearing with no seals or shields.
What internal clearance does 61917 have?
Unless a clearance suffix says otherwise, 61917 is manufactured to normal (CN) radial internal clearance. Tight fits and hot shafts consume clearance in service — for those conditions order the C3 execution of 61917 and verify the residual clearance after mounting.
How should 61917 be mounted?
Apply the mounting force to the ring being fitted: on a 85 mm shaft seat the press load must pass through the inner-ring face only. Induction heating of the inner ring (max 120 °C) is the clean method at this size. Never strike the outer ring, the cage or the seals.
What lubrication does 61917 need?
The open 61917 is lubricated by the application; a NLGI 2 lithium-soap grease filled to roughly 25–35% of the free volume is the common choice, with a defined relubrication interval.
What is the SKF designation and catalogue data for 61917?
In the SKF Rolling Bearings catalogue this size is listed as 61917 — the open (unsealed) execution, 85×120×18 mm per ISO 15. Quoted values: C 31.9 kN, C0 30 kN, Pu 1.25 kN, limiting speed 7000 r/min, mass 550 g. Brand suffixes (2Z, 2RSH, 2RSL) differ from the industry-neutral spelling 61917.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018) on 2026-09-24. Read our editorial & correction policy.