Bearing Selection
Answer four questions and we will point you to the right deep groove ball bearing from our database.
1 What is your shaft diameter?
The shaft diameter equals the bearing bore (d).
2 How heavy is the load?
Same bore, different series: a heavier series is larger outside and carries more load.
3 Do you need sealing?
Sealed bearings keep grease in and dust out; open bearings run with less friction in clean, lubricated housings.
4 Internal clearance?
CN (normal) fits most applications. C3 gives extra internal play for high speeds, high temperatures or tight interference fits.
Recommended bearing
How the series system works
For the same bore, deep groove ball bearings come in three common dimension series. Larger series means a larger outside diameter and width — and higher load ratings:
| Series | Example (20 mm bore) | Dimensions | Character |
|---|---|---|---|
| 6000 | 6004 | 20 × 42 × 12 mm | Light, compact |
| 6200 | 6204 | 20 × 47 × 14 mm | Medium, general purpose |
| 6300 | 6304 | 20 × 52 × 15 mm | Heavy duty |
This guide covers deep groove ball bearings — the most common bearing type. For combined axial loads, high-precision or special applications, other types (angular contact, tapered roller, etc.) may be more suitable.