W628-6-2RS bearing: complete specifications & equivalents
The W628-6-2RS is a ISO 15 radial bearing sized 6 x 13 x 5 mm (bore x OD x width) with 2RS sealing. Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 6 mm |
| Outer diameter D | 13 mm |
| Width B | 5 mm |
| Material | SS440C |
| Seal / shield | 2RS |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 0.618 kN |
| Basic static load rating C0 | 0.224 kN |
| Fatigue load limit Pu | 0.01 kN |
| Limiting speed (mechanical) | 30000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2.55 g |
| Manufacturer designation | W 628/6-2RS1 |
| 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 & 62800-series range
| Bore d | 0.236 in |
|---|---|
| Outer diameter D | 0.512 in |
| Width B | 0.197 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 3.5 mm |
| Smallest bore in 62800-series | 5 mm |
| Largest outer diameter in 62800-series | 24 mm |
| Width range across 62800-series | 4–8 mm |
| Bore position in 62800-series (smallest first) | 2 of 5 |
| Bore above smallest 62800-series size | 1 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| W628-6-ZZ | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 6×13×5 mm envelope and equivalent catalogue ratings; W 628/6-2Z 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 W628-6-2RS model number is decoded
The W prefix denotes SKF stainless steel deep-groove bearings (X108CrMo17 / AISI 440C class rings). In the 62800-series, the bore is written directly after the slash as 6 mm (bores below 10 mm use the slash spelling). Envelope 6×13×5 mm (0.236×0.512×0.197 in), C 0.618 kN, C0 0.224 kN, Pu 0.01 kN; limiting speed 30000 r/min and mass 2.55 g. SKF catalogues the sealed execution as W 628/6-2RS1: two contact elastomer lips (2RS1/2RSH spelling) over a lifetime grease fill; the lips add drag, and no reference (thermal) speed is published. 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
- washdown-duty equipment
- chemical and marine atmospheres
- medical and laboratory devices
- small pumps handling corrosive media
Known failure patterns
- seal and grease failure before the rings corrode in sustained washdown service
- surface staining and pitting when even the stainless steel is left unlubricated in salty or acidic duty
- contact-seal lip hardening and pre-grease loss after long high-temperature service
- grease-life expiry inside the sealed-for-life cavity, which has no relubrication path
Selection pitfalls — read before you substitute
- Food, pharmaceutical and washdown positions need food-grade grease (e.g. NSF H1 registered) inside W628-6-2RS; standard fill is industrial grease unless specified otherwise.
- Corrosion resistance depends on clean, undamaged surfaces: never weld near W628-6-2RS 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 W628-6-2RS 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 — W628-6-2RS is not marine-grade stainless.
- Deep-groove geometry tolerates only minutes of misalignment; if the 13 mm housing bore cannot be aligned, move to a self-aligning bearing rather than shimming W628-6-2RS.
- Catalogue ratings for W628-6-2RS (C 0.618 kN, C0 0.224 kN) are SKF figures from PUB BU/P1 17000; geometry revisions can change ratings without changing the designation, so keep the catalogue edition with the specification.
Frequently asked questions
What are the dimensions of the stainless W628-6-2RS?
SKF W 628/6-2RS1 measures 6×13×5 mm (0.236×0.512×0.197 in), about 2.55 g, C 0.618 kN.
What does the W in W 628/6-2RS1 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 W628-6-2RS?
The envelope matches, but stainless rates lower (C 0.618 kN for W 628/6-2RS1); 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.