W608 bearing: complete specifications & equivalents
The W608 is a ISO 15 radial bearing sized 8 x 22 x 7 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 8 mm |
| Outer diameter D | 22 mm |
| Width B | 7 mm |
| Material | SS440C |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 1.99 kN |
| Basic static load rating C0 | 0.78 kN |
| Fatigue load limit Pu | 0.034 kN |
| Reference speed (thermal) | 75000 rpm |
| Limiting speed (mechanical) | 48000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 11 g |
| Manufacturer designation | W 608 |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018) |
| Last verified | 2026-09-27 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018)) · extracted 2026-09-27
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 & 6000-series range
| Bore d | 0.315 in |
|---|---|
| Outer diameter D | 0.866 in |
| Width B | 0.276 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 7 mm |
| Smallest bore in 6000-series | 4 mm |
| Largest outer diameter in 6000-series | 1150 mm |
| Width range across 6000-series | 4–155 mm |
| Bore position in 6000-series (smallest first) | 5 of 61 |
| Bore above smallest 6000-series size | 4 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 608 | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 8×22×7 mm envelope, but the stainless and chrome-steel executions carry different catalogue ratings (1.99/0.78 kN vs 3.45/1.37 kN) — envelope match, not a load-rating equivalent; choose by corrosion versus load duty. |
| 608-2RS | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 8×22×7 mm envelope, but the stainless and chrome-steel executions carry different catalogue ratings (1.99/0.78 kN vs 3.45/1.37 kN) — envelope match, not a load-rating equivalent; choose by corrosion versus load duty. |
| 608-RSR | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 8×22×7 mm envelope, but the stainless and chrome-steel executions carry different catalogue ratings (1.99/0.78 kN vs 3.45/1.37 kN) — envelope match, not a load-rating equivalent; choose by corrosion versus load duty. |
| 608-ZZ | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 8×22×7 mm envelope, but the stainless and chrome-steel executions carry different catalogue ratings (1.99/0.78 kN vs 3.45/1.37 kN) — envelope match, not a load-rating equivalent; choose by corrosion versus load duty. |
| W608-2RS | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 8×22×7 mm envelope and equivalent catalogue ratings; W 608-2RS1 is the two contact elastomer seals execution of this size — boundary dimensions interchangeable, only the seal/shield/cage execution differs. |
| W608-ZZ | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 8×22×7 mm envelope and equivalent catalogue ratings; W 608-2Z is the two non-contact shields execution of this size — boundary dimensions interchangeable, only the seal/shield/cage execution differs. |
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 W608 model number is decoded
The W prefix denotes SKF stainless steel deep-groove bearings (X108CrMo17 / AISI 440C class rings). In the 6000-series, the final digit is the bore in millimetres: 608 fits a 8 mm shaft (direct-number miniature spelling). Envelope 8×22×7 mm (0.315×0.866×0.276 in), C 1.99 kN, C0 0.78 kN, Pu 0.034 kN; limiting speed 48000 r/min and mass 11 g. The open W 608 carries no shields or seals and relies on application lubrication and external sealing. Stainless is chosen for corrosion and washdown duty, not for extra load — the same-envelope chrome-steel bearing rates higher.
Typical equipment & failure modes
Common applications
- appliances exposed to moisture
- food and beverage conveyors
- pharmaceutical and packaging machines
- washdown-duty equipment
Known failure patterns
- surface staining and pitting when even the stainless steel is left unlubricated in salty or acidic duty
- seal and grease failure before the rings corrode in sustained washdown service
- contamination wear when the open arrangement is used without external seals
- lubricant starvation where no regreasing interval is maintained
Selection pitfalls — read before you substitute
- Corrosion resistance depends on clean, undamaged surfaces: never weld near W608 or scratch the raceways during mounting, since the damaged spot starts corrosion.
- Temperatures above roughly 300 °C temper the stainless races; even standard greases fail far earlier — keep W608 inside the quoted grease temperature range.
- W-prefix stainless rings (X108CrMo17 / AISI 440C class) resist moisture and weak chemicals but will still rust in chloride-rich or salt-spray duty without protection — W608 is not marine-grade stainless.
- The stainless steel is martensitic and MAGNETIC; do not reject W608 over magnetism — only austenitic grades are non-magnetic, and those are too soft for bearing raceways.
- At 8 mm bore, C3 clearance is the safe choice when interference fits plus temperature rise consume the CN clearance; a hot tight bearing with no residual clearance fails fast.
- Fillet radii must clear the W608 chamfer so the 7 mm-wide ring seats square; an oversized shaft radius creates point contact on the ring face.
Frequently asked questions
What are the dimensions of the stainless W608?
SKF W 608 measures 8×22×7 mm (0.315×0.866×0.276 in), about 11 g, C 1.99 kN.
What does the W in W 608 mean?
W is the SKF prefix for stainless steel deep-groove bearings (rings in X108CrMo17 / AISI 440C class); the rest of the designation follows the normal series and bore rules.
Can I replace a chrome-steel bearing with stainless W608?
The envelope matches, but stainless rates lower (C 1.99 kN for W 608); for corrosive environments that trade-off is intended, for high loads it shortens life.
Is the stainless bearing magnetic?
Yes. Bearing stainless steels are martensitic (hardened) and magnetic; non-magnetic austenitic grades cannot be hardened enough for raceways and balls.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018) on 2026-09-27. Read our editorial & correction policy.