Rolling bearings may fail during operation due to various reasons, such as improper assembly, poor lubrication, stress corrosion, and overload, all of which can lead to premature bearing failure. Rolling bearing failures have multiple failure modes, which can generally be summarized into four types: wear failure, fatigue failure, fracture failure, and seizure failure.

1. Fatigue Failure.

The main cause of rolling bearing fatigue failure is the alternating stress caused by the load. When the shaft rotates at high speed, due to the repeated impact of huge alternating contact stress on the bearing, fatigue pitting occurs on the metal surface of the bearing components, resulting in spalling and the formation of small pits.

2. Wear Failure.

Poor lubrication conditions or dust or deterioration of the lubricant can cause direct contact between the rotating parts of the bearing, leading to mechanical friction or wear by small particles. Continuous bearing wear increases the bearing clearance and increases equipment vibration.

3. Fracture Failure.

When the bearing is overloaded or subjected to impact, stress concentration occurs in a certain part of the bearing, causing pitting and cracks, which then lead to the fracture of the bearing components.