Pitting

Damage Condition	Possible Causes	Countermeasures
The pitted surface has a dull luster which appears on the rolling element surface or raceway surface.	Debris becomes caught in the lubricant Exposure to moisture in the atmosphere Poor lubrication	Improve the sealing mechanism Filter the lubrication oil thoroughly Use a proper lubricant

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Part: Outer ring of a slewing bearing
Symptom: Pitting on the raceway surface
Cause: Rust

Part: Ball of damage “Pitting 1”
Symptom: Pitting on the rolling element surface