627 bearing dimensions
A 627 bearing is 7 mm bore × 22 mm outside diameter × 7 mm wide (0.276 × 0.866 × 0.276 in). The sealed version is 627-2RS; the shielded version is 627-ZZ.
627 at a glance
Boundary dimensions in millimetres and inches, and the common closure designations.
- Bore, d
- 7 mm 0.2756"
- Outside diameter, D
- 22 mm 0.8661"
- Width, B
- 7 mm 0.2756"
- Section height, (D − d)/2
- 7.5 mm 0.2953"
- Series
- 62 series light
- Bore code
- 7 Under 10 mm bore the last digit is the bore itself: 7 = 7 mm
- Sealed, both sides
- 627-2RS
- Shielded, both sides
- 627-ZZ
- Open
- 627 no closures; any version may add C3 for extra internal clearance
Reading the number 627
Every deep groove ball bearing number follows the same pattern: type, dimension series and bore code, then suffixes.
Seals, shields and suffixes
Suffixes add closures and internal clearance. They do not change the boundary dimensions: a sealed and an open bearing of the same number are interchangeable in size.
| Suffix | Meaning | 627 example |
|---|---|---|
| Open (no suffix) | No seals or shields. Can be relubricated, or run in an oil bath; the housing needs its own seal against dirt. | 627 |
| Z | One metal shield, on one side only. | 627-Z |
| ZZ, 2Z | Metal shields on both sides. Non-contact, so low friction; keeps out larger dirt. Usually greased for life. | 627-ZZ |
| RS | One rubber contact seal, on one side only. | 627-RS |
| 2RS, 2RS1, 2RSH, 2RSR, DDU, LLU | Rubber contact seals on both sides. Better than shields against fine dirt and splashing water, with a little more friction. Usually greased for life. | 627-2RS |
| C3 | Radial internal clearance greater than normal (CN). Used with tight shaft or housing fits, or where the inner ring runs hotter than the outer ring. | 627-2RS C3 |
627 in other brands
The sealed and shielded versions as each maker writes them. All share the same boundary dimensions.
| Maker | Sealed both sides | Shielded both sides |
|---|---|---|
| SKF | 627-2RSH | 627-2Z |
| FAG (Schaeffler) | 627-2RSR | 627-2ZR |
| NSK | 627DDU | 627ZZ |
| NTN | 627LLU | 627ZZ |
| Koyo (JTEKT) | 627-2RS | 627ZZ |
| Timken | 627-2RS | see catalogue |
Seal designs and suffixes vary by maker, size range and product generation, for example contact versus low-friction seals. Confirm the exact designation in the maker's catalogue before ordering.
Same 7 mm bore, other series
Bearings that fit the same shaft. A heavier series carries more load in a bigger housing bore; a thin-section series saves space and weight.
| Bearing | Series | OD | Width | Section | vs 627 |
|---|---|---|---|---|---|
| 607 | extra-light | 19 mm | 6 mm | 6 mm | −3 mm OD, −1 mm wide |
| 627 | light | 22 mm | 7 mm | 7.5 mm | this bearing |
Miniature bearings
Common questions
What size is a 627 bearing?
7 mm bore, 22 mm outside diameter and 7 mm wide, which is 0.276 × 0.866 × 0.276 in.
What does 2RS mean on a 627 bearing?
627-2RS has rubber contact seals on both sides. 627-ZZ (also written 627-2Z) has metal shields on both sides. Both have the same 7 × 22 × 7 mm dimensions.
Is 627-2RS the same as 627-ZZ?
They are the same size and interchangeable in a housing. The sealed 627-2RS keeps out fine dirt and water better; the shielded 627-ZZ runs with less friction.
What is the SKF equivalent of 627-2RS?
SKF writes it 627-2RSH; FAG 627-2RSR, NSK 627DDU, NTN 627LLU and Koyo 627-2RS. Check the maker's catalogue for the exact seal type.
What does the number 627 mean?
6 is the deep groove ball bearing type, 2 is the light dimension series, and under 10 mm bore the last digit is the bore itself: 7 = 7 mm.
Which bearings have the same bore as 627?
607 also have a 7 mm bore, with different outside diameters and widths.