When a rolling bearing is damaged during machine operation, the entire machine or equipment can seize or malfunction. Since bearings that fail prematurely or unexpectedly cause trouble, it is important to be able to identify and predict failure beforehand, so that preventive measures can be adopted.

Damage Condition

Among the different types of Fretting, false brinelling is the occurrence of hollow spots that resemble brinell dents and are due to Wear caused by vibration and swaying at the contact points between the rolling elements and raceway.

Possible Causes Oscillation and vibration of a stationary bearing during such times as transporting Oscillating motion with a small amplitude Poor lubrication Countermeasures Secure the shaft and housing during transporting Transport with the inner and outer rings packed separately Reduce the vibration by preloading Use a proper lubricant

False Brinelling 1

Part: Inner ring of a deep groove ball bearing
Symptom: False brinelling on the raceway
Cause: Vibration from an external source while stationary

False Brinelling 2

Part: Outer ring of damage “False Brinelling 1”
Symptom: False brinelling on the raceway
Cause: Vibration from an external source while stationary

False Brinelling 3

Part: Outer ring of a thrust ball bearing
Symptom: False brinelling of raceway surface at ball pitch
Cause: Repeated vibration with a small oscillating angle

False Brinelling 4

Part: Rollers of a cylindrical roller bearing
Symptom: False brinelling on rolling surface
Cause: Vibration from an external source while stationary

Source: NSK