BEARINGDEXDeep groove ball, miniature
634 bearing
4 mm bore, 16 mm outside diameter, 5 mm width (0.1575 × 0.6299 × 0.1969 in).
Dimensions
| mm | inch | |
|---|---|---|
| Bore d | 4 | 0.1575 |
| Outside diameter D | 16 | 0.6299 |
| Width B | 5 | 0.1969 |
Quick numbers
| Pitch diameter dm | 10.0 mm |
| Section height (D − d)/2 | 6.0 mm |
| n·dm at 1,800 rpm | 18,000 |
| n·dm at 3,600 rpm | 36,000 |
Compare against the maker's limiting speed. Speed calculator · L10 life
What the number means
6Deep groove ball
3Diameter series 3: medium
4Single digit: bore is 4 mm, written directly
How each brand writes it
Same bearing, every maker's notation| Version | SKF | FAG | NSK | NTN | Koyo | NACHI |
|---|---|---|---|---|---|---|
| Open | 634 | 634 | 634 | 634 | 634 | 634 |
| Shields both sides | 634-2Z | 634-2ZR | 634ZZ | 634ZZ | 634ZZ | 634ZZE |
| Contact seals both sides | 634-2RSH | 634-2RSR | 634DDU | 634LLU | 634-2RS | 634-2NSE |
| Contact seals both sides, C3 | 634-2RSH/C3 | 634-2RSR-C3 | 634DDUC3 | 634LLUC3 | 634-2RSC3 | 634-2NSE C3 Verify |
| Non-contact seals both sides | 634-2RSL | 634-2BRS Verify | 634VV | 634LLB | 634-2RU Verify | 634-2NKE Verify |
| Shields both sides, C3 | 634-2Z/C3 | 634-2ZR-C3 | 634ZZC3 | 634ZZC3 | 634ZZC3 | 634ZZE C3 Verify |