BEARINGDEXDeep groove ball
6318 bearing
90 mm bore, 190 mm outside diameter, 43 mm width (3.5433 × 7.4803 × 1.6929 in).
Dimensions
| mm | inch | |
|---|---|---|
| Bore d | 90 | 3.5433 |
| Outside diameter D | 190 | 7.4803 |
| Width B | 43 | 1.6929 |
Quick numbers
| Pitch diameter dm | 140.0 mm |
| Section height (D − d)/2 | 50.0 mm |
| n·dm at 1,800 rpm | 252,000 |
| n·dm at 3,600 rpm | 504,000 |
Compare against the maker's limiting speed. Speed calculator · L10 life
What the number means
6Deep groove ball
3Diameter series 3: medium. Width series 0 is implied and left off.
18Bore code 18 × 5 = 90 mm
How each brand writes it
Same bearing, every maker's notation| Version | SKF | FAG | NSK | NTN | Koyo | NACHI |
|---|---|---|---|---|---|---|
| Open | 6318 | 6318 | 6318 | 6318 | 6318 | 6318 |
| Shields both sides | 6318-2Z | 6318-2ZR | 6318ZZ | 6318ZZ | 6318ZZ | 6318ZZE |
| Contact seals both sides | 6318-2RSH | 6318-2RSR | 6318DDU | 6318LLU | 6318-2RS | 6318-2NSE |
| Contact seals both sides, C3 | 6318-2RSH/C3 | 6318-2RSR-C3 | 6318DDUC3 | 6318LLUC3 | 6318-2RSC3 | 6318-2NSE C3 Verify |
| Non-contact seals both sides | 6318-2RSL | 6318-2BRS Verify | 6318VV | 6318LLB | 6318-2RU Verify | 6318-2NKE Verify |
| Shields both sides, C3 | 6318-2Z/C3 | 6318-2ZR-C3 | 6318ZZC3 | 6318ZZC3 | 6318ZZC3 | 6318ZZE C3 Verify |
Same size, different bearing
These share the 90 × 190 × 43 mm envelope but carry load differently. They aren't drop-in swaps.