A bearing supports a rotating shaft while minimizing friction. Selecting one starts with the direction of load it must carry.
| Bearing type | Best for |
|---|---|
| Ball bearing | Moderate radial + some axial load, high speed |
| Cylindrical roller | Heavy radial loads |
| Tapered roller | Combined radial + axial (e.g., wheel hubs) |
| Thrust bearing | Axial (push-along-shaft) loads |
Key selection factors
Beyond load direction, match the magnitude of the load (its dynamic and static load ratings must exceed your loads with margin), the speed (every bearing has a limiting speed), and the life required. Bearing life is usually given as L10 — the number of revolutions (or hours) that 90% of bearings will reach before fatigue. Also consider lubrication, sealing against contamination, and operating temperature.
Frequently asked questions
What bearing for axial loads? A thrust bearing (or tapered roller for combined loads).
What is L10 life? The life 90% of bearings will reach before fatigue failure.
What matters most in selection? Load direction first, then magnitude, speed, and required life.