Damage Condition Possible Causes Countermeasures

Bearing rust and corrosion are pits on the surface of rings and rolling elements and may occur at the rolling element pitch on the rings or over the entire bearing surfaces

Entry of corrosive gas or water
Improper lubricant
Formation of water droplets due to condensation of moisture
High temperature and high humidity while stationary
Poor rust-preventive treatment during transporting
Improper storage conditions
Improper handling
  • Improve the sealing mechanis
  • Study the lubrication method
  • Anti-rust treatment during periods of non-running
  • Improve the storage methods
  • Improve the handling method

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Rust and Corrosion 1

Rust and Corrosion 1

Part : Outer ring of a cylindrical roller bearing
Symptom : Rust on the rib face and raceway surface
Cause : Water entry

Rust and Corrosion 2

Rust and Corrosion 2

Part : Outer ring of a slewing ring
Symptom : Rust on raceway surface at ball pitch intervals
Cause : Moisture condensation during stationary periods


Rust and Corrosion 3

Rust and Corrosion 3

Part : Inner ring of a spherical roller bearing
Symptom : Rust on raceway surface at roller pitch intervals
Cause : Entry of water into lubricant

Rust and Corrosion 4

Rust and Corrosion 4

Part : Rollers of a spherical roller bearing
Symptom : Pit-shaped rust on rolling contact surface. Corroded portions.
Cause : Moisture condensation during storage



Motion & Control