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Fretting and Fretting Corrosion

Fretting and Fretting Corrosion

Condition
  • Fretting surfaces wear producing red rust colored particles that form hollows.
  • On the raceway surface, dents called false brinelling are formed at spacing equal to distances corresponding to the rolling elements.
Cause
  • If a vibrating load works on contacting elements resulting in small amplitude oscillation, lubricant is driven out form contact, and parts are worn remarkably.
  • Oscillation angle of the bearing is small.
  • Poor lubrication (no lubrication)
  • Fluctuating load
  • Vibration during transportation
Solution
  1. Inner ring and outer ring should be packaged separately for transportation. If not separable, bearings should be preloaded.
  2. Use oil or high consistency grease when bearings are used for oscillation motion.
  3. Change lubricant
Cause
  • Vibration, shaft deflection, installation error, loose fit.
Solution
  1. Fix shaft and housing
  2. Improve fit

Photo: Inner ring of cylindrical roller bearing.

  • Inner ring of cylindrical roller bearing.
  • Corrugated fretting along full circumference of raceway.
  • The cause is vibration.

Photo: Inner ring of deep groove ball bearing.

  • Inner ring of deep groove ball bearing.
  • Fretting along full circumference of raceway.
  • The cause is vibration.

Photo: Outer ring of cylindrical roller bearing

  • Outer ring of cylindrical roller bearing
  • Fretting rust on outside diameter surface

Photo: Outer ring of tapered roller bearing

  • Outer ring of tapered roller bearing
  • Fretting rust on the outside diameter surface