6307 bearing dimensions
A 6307 bearing is 35 mm bore × 80 mm outside diameter × 21 mm wide (1.378 × 3.150 × 0.827 in). The sealed version is 6307-2RS; the shielded version is 6307-ZZ.
6307 at a glance
Boundary dimensions in millimetres and inches, and the common closure designations.
- Bore, d
- 35 mm 1.3780"
- Outside diameter, D
- 80 mm 3.1496"
- Width, B
- 21 mm 0.8268"
- Section height, (D − d)/2
- 22.5 mm 0.8858"
- Series
- 63 series medium
- Bore code
- 07 07 × 5 = 35 mm
- Sealed, both sides
- 6307-2RS
- Shielded, both sides
- 6307-ZZ
- Open
- 6307 no closures; any version may add C3 for extra internal clearance
Reading the number 6307
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 | 6307 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. | 6307 |
| Z | One metal shield, on one side only. | 6307-Z |
| ZZ, 2Z | Metal shields on both sides. Non-contact, so low friction; keeps out larger dirt. Usually greased for life. | 6307-ZZ |
| RS | One rubber contact seal, on one side only. | 6307-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. | 6307-2RS |
| 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. | 6307-2RS C3 |
6307 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 | 6307-2RSH | 6307-2Z |
| FAG (Schaeffler) | 6307-2RSR | 6307-2ZR |
| NSK | 6307DDU | 6307ZZ |
| NTN | 6307LLU | 6307ZZ |
| Koyo (JTEKT) | 6307-2RS | 6307ZZ |
| Timken | 6307-2RS | 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 35 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 6307 |
|---|---|---|---|---|---|
| 6807 | thin-section | 47 mm | 7 mm | 6 mm | −33 mm OD, −14 mm wide |
| 6907 | thin-section | 55 mm | 10 mm | 10 mm | −25 mm OD, −11 mm wide |
| 6007 | extra-light | 62 mm | 14 mm | 13.5 mm | −18 mm OD, −7 mm wide |
| 6207 | light | 72 mm | 17 mm | 18.5 mm | −8 mm OD, −4 mm wide |
| 6307 | medium | 80 mm | 21 mm | 22.5 mm | this bearing |
63 series
Common questions
What size is a 6307 bearing?
35 mm bore, 80 mm outside diameter and 21 mm wide, which is 1.378 × 3.150 × 0.827 in.
What does 2RS mean on a 6307 bearing?
6307-2RS has rubber contact seals on both sides. 6307-ZZ (also written 6307-2Z) has metal shields on both sides. Both have the same 35 × 80 × 21 mm dimensions.
Is 6307-2RS the same as 6307-ZZ?
They are the same size and interchangeable in a housing. The sealed 6307-2RS keeps out fine dirt and water better; the shielded 6307-ZZ runs with less friction.
What is the SKF equivalent of 6307-2RS?
SKF writes it 6307-2RSH; FAG 6307-2RSR, NSK 6307DDU, NTN 6307LLU and Koyo 6307-2RS. Check the maker's catalogue for the exact seal type.
What does the number 6307 mean?
6 is the deep groove ball bearing type, 3 is the medium dimension series, and 07 × 5 = 35 mm (from 04 up, multiply by 5).
Which bearings have the same bore as 6307?
6807, 6907, 6007, 6207 also have a 35 mm bore, with different outside diameters and widths.