6304 Bearing Dimensions and SKF Specifications
20 × 52 × 15 mm — single-row deep groove ball bearing
SKF Open 6304 Specifications
| Property | SKF catalog value |
|---|---|
| Bore diameter (d) | 20 mm |
| Outside diameter (D) | 52 mm |
| Width (B) | 15 mm |
| Basic dynamic load rating (C) | 16.8 kN |
| Basic static load rating (C0) | 7.8 kN |
| Reference speed | 30,000 r/min |
| Limiting speed | 19,000 r/min |
These values apply to the SKF open 6304 designation in the cited catalog. Reference speed and limiting speed are separate measures. Neither is a universal application speed recommendation. Sealed, shielded and special internal designs require their own specifications.
Source: SKF single-row deep groove ball bearing catalog table. The official indexed catalog row was checked on 11 October 2026. Catalog edition and current product-sheet confirmation remain pending.
Replacement Candidates and Evidence
SKF 6304 boundary dimensions are sourced above. Other brand designations below are inherited candidates awaiting source review. A shared base number does not establish interchangeability or supplier stock availability.
| Manufacturer | Candidate designation | Evidence |
|---|---|---|
| FAG (Schaeffler) | 6304 | Unverified candidate |
| NSK | 6304 | Unverified candidate |
| Timken | 6304 | Unverified candidate |
| NTN | 6304 | Unverified candidate |
| Koyo (JTEKT) | 6304 | Unverified candidate |
| NACHI | 6304 | Unverified candidate |
Before Selecting a Replacement
Record the complete marking on the original bearing. Verify bore, outside diameter and width, then compare seals or shields, internal clearance, cage, tolerances, lubrication and load and speed requirements against the exact manufacturer variant and equipment specification.
C3 describes internal clearance; it is not a quality grade. Closure suffixes differ between manufacturers. Do not infer the complete configuration from the base number alone.
Preserve prefixes, suffixes, slashes and hyphens when searching. Missing information remains unknown until sourced.