# 6312 bearing dimensions

A 6312 bearing is 60 mm bore × 130 mm outside diameter × 31 mm wide (2.362 × 5.118 × 1.220 in). The sealed version is 6312-2RS; the shielded version is 6312-ZZ.

## 6312 data

- Type: deep groove ball bearing, 63 series (medium)
- Bore d: 60 mm (2.3622 in)
- Outside diameter D: 130 mm (5.1181 in)
- Width B: 31 mm (1.2205 in)
- Bore code: 12 × 5 = 60 mm (from 04 up, multiply by 5)
- Sealed: 6312-2RS; shielded: 6312-ZZ; open: 6312

## Designations by maker

| Maker | Sealed | Shielded |
|---|---|---|
| SKF | 6312-2RSH | 6312-2Z |
| FAG (Schaeffler) | 6312-2RSR | 6312-2ZR |
| NSK | 6312DDU | 6312ZZ |
| NTN | 6312LLU | 6312ZZ |
| Koyo (JTEKT) | 6312-2RS | 6312ZZ |
| Timken | 6312-2RS | see catalogue |

## Same 60 mm bore, other series

| Bearing | Series | OD mm | Width mm |
|---|---|---|---|
| 6012 | extra-light | 95 | 18 |
| 6212 | light | 110 | 22 |
| 6312 | medium | 130 | 31 |


Load ratings and speed limits vary by maker: take them from the manufacturer's catalogue.

## FAQ

**What size is a 6312 bearing?**
60 mm bore, 130 mm outside diameter and 31 mm wide, which is 2.362 × 5.118 × 1.220 in.

**What does 2RS mean on a 6312 bearing?**
6312-2RS has rubber contact seals on both sides. 6312-ZZ (also written 6312-2Z) has metal shields on both sides. Both have the same 60 × 130 × 31 mm dimensions.

**Is 6312-2RS the same as 6312-ZZ?**
They are the same size and interchangeable in a housing. The sealed 6312-2RS keeps out fine dirt and water better; the shielded 6312-ZZ runs with less friction.

**What is the SKF equivalent of 6312-2RS?**
SKF writes it 6312-2RSH; FAG 6312-2RSR, NSK 6312DDU, NTN 6312LLU and Koyo 6312-2RS. Check the maker's catalogue for the exact seal type.

**What does the number 6312 mean?**
6 is the deep groove ball bearing type, 3 is the medium dimension series, and 12 × 5 = 60 mm (from 04 up, multiply by 5).

**Which bearings have the same bore as 6312?**
6012, 6212 also have a 60 mm bore, with different outside diameters and widths.

Source page: https://machinistcharts.com/bearing/6312/
Updated: 2026-10-06
Publisher: MachinistCharts (https://machinistcharts.com)