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Flaking

Flaking

Condition Cause Solution
  • Raceway surface is flaked.
  • Surface after flaking is very rough.
  • Rolling fatigue.
  • Flaking may be caused early by over-load, excessive load due to improper handling, poor shaft or housing accuracy, installation error, ingress of foreign objects, rusting, etc.
  1. Find the cause of the heavy load.
  2. Examine operating conditions and adopt bearings with larger capacity as necessary.
  3. Increase viscosity of oil and improve lubrication system to form an adequate lubricating oil film.
  4. Eliminate installation errors.

Photo: Deep groove ball bearing

  • Deep groove ball bearing
  • Inner ring, outer ring, and balls are flaked.
  • The cause is excessive load.

Photo: Outer ring of angular contact ball bearing

  • Outer ring of angular contact ball bearing
  • Making of raceway surface spacing equal to distances between balls.
  • The cause is improper handling.

Photo: Inner ring raceway of a deep groove ball bearing

  • Inner ring raceway of a deep groove ball bearing

Photo: Outer ring raceway of an angular contact ball bearing

  • Outer ring raceway of an angular contact ball bearing

Photo: Inner ring of deep groove ball bearing

  • Inner ring of deep groove ball bearing
  • Flaking on one side of the raceway surface
  • The cause is an excessive axial load.

Photo: Inner ring of spherical roller bearing.

  • Inner ring of spherical roller bearing.
  • Flaking only on one side of the raceway surface.
  • The cause is an excessive axial load.

Photo: Tapered roller bearing

  • Tapered roller bearing
  • Flaking on 1/4 circumference of inner ring raceway with outer ring and rollers discolored light brown.
  • The cause is excessive pre-load.

Photo: Outer ring of double row angular contact ball bearing.

  • Outer ring of double row angular contact ball bearing.
  • Flaking on 1/4 circumference of outer ring raceway.
  • The cause is poor installation.

Photo: Thrust ball bearing

  • Thrust ball bearing
  • Flaking on inner ring raceway (bearing ring fastened to shaft) and balls.
  • The cause is poor lubrication

Photo: Outer ring raceway of double row tapered roller bearing (RCT bearing)

  • Outer ring raceway of double row tapered roller bearing (RCT bearing)
  • Flaking originated from electric pitting on the raceway surface (refer to Section "Electrical Pitting").