|Damage Condition||Possible Causes||Countermeasures|
When electric current passes through a bearing, arcing and burning occur through the thin oil film at points of contact between the raceway and rolling elements. The points of contact are melted locally to form "fluting" or groove-like corrugations which can be seen by the naked eye.
Electric current passing through a bearing
Part : Inner ring of a tapered roller bearing
Symptom : Striped pattern of corrosion occurs on the raceway surface
Part : Tapered rollers of damage "ELECTRICAL CORROSION 1"
Symptom : Striped pattern of corrosion occurs on the rolling surface
Part : Inner ring of a cylindrical roller bearing
Symptom : Belt pattern of electrical corrosion accompanied by pits on the raceway surface
Part : Balls of a deep groove ball bearing
Symptom : Dark color covering the entire ball surfaces