6310 bearing dimensions
A 6310 bearing is 50 mm bore × 110 mm outside diameter × 27 mm wide (1.969 × 4.331 × 1.063 in). The sealed version is 6310-2RS; the shielded version is 6310-ZZ.
6310 at a glance
Boundary dimensions in millimetres and inches, and the common closure designations.
- Bore, d
- 50 mm 1.9685"
- Outside diameter, D
- 110 mm 4.3307"
- Width, B
- 27 mm 1.0630"
- Section height, (D − d)/2
- 30 mm 1.1811"
- Series
- 63 series medium
- Bore code
- 10 10 × 5 = 50 mm
- Sealed, both sides
- 6310-2RS
- Shielded, both sides
- 6310-ZZ
- Open
- 6310 no closures; any version may add C3 for extra internal clearance
Reading the number 6310
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 | 6310 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. | 6310 |
| Z | One metal shield, on one side only. | 6310-Z |
| ZZ, 2Z | Metal shields on both sides. Non-contact, so low friction; keeps out larger dirt. Usually greased for life. | 6310-ZZ |
| RS | One rubber contact seal, on one side only. | 6310-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. | 6310-2RS |
| 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. | 6310-2RS C3 |
6310 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 | 6310-2RSH | 6310-2Z |
| FAG (Schaeffler) | 6310-2RSR | 6310-2ZR |
| NSK | 6310DDU | 6310ZZ |
| NTN | 6310LLU | 6310ZZ |
| Koyo (JTEKT) | 6310-2RS | 6310ZZ |
| Timken | 6310-2RS | 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 50 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 6310 |
|---|---|---|---|---|---|
| 6810 | thin-section | 65 mm | 7 mm | 7.5 mm | −45 mm OD, −20 mm wide |
| 6910 | thin-section | 72 mm | 12 mm | 11 mm | −38 mm OD, −15 mm wide |
| 6010 | extra-light | 80 mm | 16 mm | 15 mm | −30 mm OD, −11 mm wide |
| 6210 | light | 90 mm | 20 mm | 20 mm | −20 mm OD, −7 mm wide |
| 6310 | medium | 110 mm | 27 mm | 30 mm | this bearing |
63 series
Common questions
What size is a 6310 bearing?
50 mm bore, 110 mm outside diameter and 27 mm wide, which is 1.969 × 4.331 × 1.063 in.
What does 2RS mean on a 6310 bearing?
6310-2RS has rubber contact seals on both sides. 6310-ZZ (also written 6310-2Z) has metal shields on both sides. Both have the same 50 × 110 × 27 mm dimensions.
Is 6310-2RS the same as 6310-ZZ?
They are the same size and interchangeable in a housing. The sealed 6310-2RS keeps out fine dirt and water better; the shielded 6310-ZZ runs with less friction.
What is the SKF equivalent of 6310-2RS?
SKF writes it 6310-2RSH; FAG 6310-2RSR, NSK 6310DDU, NTN 6310LLU and Koyo 6310-2RS. Check the maker's catalogue for the exact seal type.
What does the number 6310 mean?
6 is the deep groove ball bearing type, 3 is the medium dimension series, and 10 × 5 = 50 mm (from 04 up, multiply by 5).
Which bearings have the same bore as 6310?
6810, 6910, 6010, 6210 also have a 50 mm bore, with different outside diameters and widths.