628-7-ZZ bearing: complete specifications & equivalents
The 628-7-ZZ is a ISO 15 radial bearing sized 7 x 14 x 5 mm (bore x OD x width) with ZZ sealing. Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 7 mm |
| Outer diameter D | 14 mm |
| Width B | 5 mm |
| Material | GCr15 |
| Seal / shield | ZZ |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 0.956 kN |
| Basic static load rating C0 | 0.4 kN |
| Fatigue load limit Pu | 0.017 kN |
| Reference speed (thermal) | 100000 rpm |
| Limiting speed (mechanical) | 50000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 3.1 g |
| Manufacturer designation | 628/7-2Z |
| 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 | 0.276 in |
|---|---|
| Outer diameter D | 0.551 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) | 3 of 5 |
| Bore above smallest 62800-series size | 2 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| W628-7-ZZ | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 7×14×5 mm envelope, but the stainless and chrome-steel executions carry different catalogue ratings (0.956/0.4 kN vs 0.663/0.26 kN) — envelope match, not a load-rating equivalent; choose by corrosion versus load duty. |
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 628-7-ZZ model number is decoded
In the miniature 62800-series, the bore is written directly after the slash as 7 mm (bores below 10 mm use the slash spelling). The envelope is 7×14×5 mm (0.276×0.551×0.197 in) with a 3.5 mm radial section height, C 0.956 kN, C0 0.4 kN and Pu 0.017 kN. SKF spells the double shield 628/7-2Z (suffix 2Z); the shields are non-contact, retain grease and block coarse debris but are not liquid-tight. Limiting speed 50000 r/min, catalogue mass 3.1 g. A thin section saves space but leaves little margin for misalignment or shaft deflection.
Typical equipment & failure modes
Common applications
- small fans and blowers
- hand-held power tools
- domestic appliances
- instrument and encoder drives
Known failure patterns
- fine-particle abrasion when non-contact shields let dust through in a dirty environment
- grease aging inside the shielded cavity with no relubrication path
- fretting corrosion on a creeping shaft or housing seat
- cage damage from running beyond the limiting speed
Selection pitfalls — read before you substitute
- Fillet radii must clear the 628-7-ZZ chamfer so the 5 mm-wide ring seats square; an oversized shaft radius creates point contact on the ring face.
- The fatigue load limit is 0.017 kN; it feeds the equivalent-mean-load check, not the basic life calculation — do not substitute one for the other.
- Shields on 628-7-ZZ are non-contact: chips and coarse dust stay out, but water passes straight through — specify the sealed 628/7-2RS for washdown duty.
- Do not pry the caps off 628-7-ZZ to repack it; shield/seal damage leaves a gap that throws grease and admits dirt.
- Mount by heating the inner ring (max 120 °C) — driving 628-7-ZZ home through the outer ring or balls brinells the raceways.
- The fatigue load limit is 0.017 kN; it feeds the equivalent-mean-load check, not the basic life calculation — do not substitute one for the other.
Frequently asked questions
What are the dimensions of 628-7-ZZ?
The SKF 628/7-2Z measures 7 mm bore × 14 mm OD × 5 mm width (0.276 × 0.551 × 0.197 in), mass about 3.1 g. It has two non-contact sheet-metal shields.
Why is there a slash in the designation 628/7-2Z?
The slash writes a bore that falls outside the two-digit code table: 628/7 means 7 mm bore. The site slug 628-7-ZZ replaces the slash with a hyphen.
What load can 628-7-ZZ take?
Catalogue values for 628/7-2Z: dynamic C 0.956 kN, static C0 0.4 kN, fatigue limit Pu 0.017 kN. Use C in life calculation and C0 for static checks at 7 mm bore.
What is the speed rating of 628-7-ZZ?
SKF lists a 100000 r/min thermal reference speed and a 50000 r/min mechanical limiting speed for 628/7-2Z; real limits also depend on lubrication and fits.
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.