61940 bearing: complete specifications & equivalents
The 61940 is a ISO 15 radial bearing sized 200 x 280 x 38 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 200 mm |
| Outer diameter D | 280 mm |
| Width B | 38 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 | 148 kN |
| Basic static load rating C0 | 166 kN |
| Fatigue load limit Pu | 4.55 kN |
| Reference speed (thermal) | 4800 rpm |
| Limiting speed (mechanical) | 3000 rpm |
| Operating temperature | -40 to +150 °C |
| Mass | 6300 g |
| Manufacturer designation | SKF 61940 |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018) |
| Last verified | 2026-09-25 |
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 | 7.874 in |
|---|---|
| Outer diameter D | 11.024 in |
| Width B | 1.496 in |
| ISO bore code | 40 |
| Radial section height (D−d)/2 | 40 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) | 39 of 63 |
| Bore above smallest 61900-series size | 197 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 61940-FAG | FAG | 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. |
| 61940 | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier. |
| 61940-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. |
| 61940-ZZ | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 200×280×38 mm envelope per ISO 15; seal variant differs (OPEN vs ZZ) — confirm sealing suits the duty. |
| 61940-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 200×280×38 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
| 61940-MA | SKF | full Dimensions and internal design equivalent — standard interchange. | SKF 61940 MA (machined brass cage, open arrangement) is the same-size execution on the 200×280×38 mm envelope with ratings within 10 % — boundary dimensions interchangeable. |
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 61940 model number is decoded
61940 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 40 by five gives the 200 mm bore; the 280 mm outside diameter and 38 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 200 mm shaft under normal load, catalogue practice seats it on a m6 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
- edge loading from shaft deflection or housing misalignment
- rolling-contact fatigue spalling after the rated L10 life is exceeded
Selection pitfalls — read before you substitute
- Large bores like the 200 mm of 61940 demand clean, burr-free seats; one raised burr under a ring this size cocks the bearing and concentrates load at the raceway edge, cutting life drastically.
- The 619xx thin section at 200 mm bore (40.0 mm section height) cannot shrug off the misalignment a standard section tolerates; keep the housing bores round and aligned, or edge contact will spall the raceways early.
- The open 61940 has no lubricant retention: grease escapes and contaminants migrate straight into the 200×280×38 mm raceway, so specify a sealed arrangement for dusty or washdown duty.
- Storage matters for open bearings: 61940 leaves the factory with rust preventive only, so clean it and apply the service grease at assembly even if the rings look oily from the wrapper.
- Deep-groove ball bearings tolerate only minutes of misalignment; if the 280 mm housing cannot be aligned, switch to a self-aligning type rather than shimming 61940.
- Vibration during standstill brinells the raceways of a 200 mm bearing at ball spacing; if the machine sits idle next to running equipment, turn the shaft over periodically or isolate the arrangement.
- The open 61940 needs external sealing and application-supplied lubrication; in the SKF catalogue the protected variants are separate order numbers 61940-2Z (shields) and 61940-2RSH (contact seals), not suffix-free 61940.
- The 148/166 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 61940 bearing?
A 61940 deep-groove ball bearing has a 200 mm bore, 280 mm outer diameter and 38 mm width (7.874 × 11.024 × 1.496 in), per ISO 15 boundary dimensions. It is an open bearing with no seals or shields.
What internal clearance does 61940 have?
Unless a clearance suffix says otherwise, 61940 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 61940 and verify the residual clearance after mounting.
How should 61940 be mounted?
Apply the mounting force to the ring being fitted: on a 200 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 61940 need?
The open 61940 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 61940?
In the SKF Rolling Bearings catalogue this size is listed as 61940 — the open (unsealed) execution, 200×280×38 mm per ISO 15. Quoted values: C 148 kN, C0 166 kN, Pu 4.55 kN, limiting speed 3000 r/min, mass 6300 g. Brand suffixes (2Z, 2RSH, 2RSL) differ from the industry-neutral spelling 61940.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018) on 2026-09-25. Read our editorial & correction policy.