Damage Condition Possible Causes Countermeasures

When sudden overheating occurs during rotation, the bearing becomes discolored. Then, the raceway rings, rolling elements, and cage will soften, melt and deform as damage accumulates.

Poor lubrication
Excessive load (Excessive preload)
Excessive rotational speed
Excessively small internal clearance
Entry of water and debris
Poor precision of shaft and housing Excessive shaft bending
  • Study the lubricant and lubrication method
  • Reinvestigate the suitability of the bearing type selected
  • Study the preload, bearing clearance, and fitting
  • Improve the sealing mechanism
  • Check the precision of the shaft and housing
  • Improve the mounting method

Click a photo to enlarge it

Seizure 1

Seizure 1

Part : Inner ring of a spherical roller bearing
Symptom : Raceway is discolored and melted. Worn particles from the cage were rolled and attached to the raceway.
Cause : Insufficient lubrication

Seizure 2

Seizure 2

Part : Convex rollers of damage "SEIZURE 1"
Symptom : Discoloration and melting of roller rolling surface, adhesion of worn particles from cage
Cause : Insufficient lubrication


Seizure 3

Seizure 3

Part : Inner ring of an angular contact ball bearing
Symptom : Raceway Discoloration, melting at ball pitch intervals
Cause : Excessive preload

Seizure 4

Seizure 4

Part : Outer ring of damage "SEIZURE 3"
Symptom : Raceway Discoloration, melting at ball pitch intervals
Cause : Excessive preload


Seizure 5

Seizure 5

Part : Balls and cage of damage "SEIZURE 3"
Symptom : Cage is damaged by melting, balls discolored and melted
Cause : Excessive preload


Motion & Control