| Bearing number | 638-RZ |
| Size (mm) | 8x28x6 |
| Bore Diameter (mm) | 8 |
| Outer Diameter (mm) | 28 |
| Width (mm) | 6 |
| d | 8 mm |
| D | 28 mm |
| B | 6 mm |
| C | 6 mm |
| d1 | 14,8 mm |
| d2 | – mm |
| r1 min. | 10,4 mm |
| r2 min. | 10,4 mm |
| D1 | 22,6 mm |
| D2 | 0,3 mm |
| da min. | 10.4 mm |
| Da max. | 25.6 mm |
| ra max. | 0.3 mm |
| Weight | 0,03 Kg |
| Basic dynamic load rating (C) | 1,33 kN |
| Basic static load rating (C0) | 0,57 kN |
| Fatigue load limit (Pu) | 0,024 |
| Reference speed | 60000 r/min |
| Limiting speed | 30000 r/min |
| Calculation factor (f0) | 12 |
| d1 ≈ | 14.8 mm |
| D2 ≈ | 22.6 mm |
| r1,2 min. | 0.3 mm |
| da max. | 14.7 mm |
| Basic dynamic load rating C | 1.33 kN |
| Basic static load rating C0 | 0.57 kN |
| Fatigue load limit Pu | 0.024 kN |
| Calculation factor kr | 0.03 |
| Calculation factor f0 | 12 |
| Mass bearing | 0.03 kg |
