Damage Condition Possible Causes Countermeasures

Straight line scratches on surface of raceways or rolling elements caused during mounting or dismounting of bearing

Inclination of inner and outer rings during mounting or dismounting
Shock load during mounting or dismounting
  • Use appropriate jig and tools
  • Avoid shock loads by using a press machine
  • Center the relative mating parts during mounting

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Mounting Flaws 1

Mounting Flaws 1

Part : Inner ring of a cylindrical roller bearing
Symptom : Axial scratches on raceway surface
Cause : Inclination of inner and outer rings during mounting

Mounting Flaws 2

Mounting Flaws 2

Part : Outer ring of a double-row cylindrical roller bearing
Symptom : Axial scratches at roller pitch intervals on raceway surface
Cause : Inclination of inner and outer rings during mounting


Mounting Flaws 3

Mounting Flaws 3

Part : Rollers of a cylindrical roller bearing
Symptom : Axial scratches on rolling surface
Cause : Inclination of inner and outer rings during mounting


Motion & Control