MENU AM/ENAM/EN Search NSK - Motion & Control
Damage Condition Possible Causes Countermeasures
Cracks in the raceway ring and rolling elements. Continued use under this condition leads to larger Cracks or Fractures.
  • Excessive interference
  • Excessive load, shock load
  • Progression of Flaking
  • Heat generation and Fretting caused by contact between mounting parts and raceway ring
  • Heat generation due to Creep
  • Poor taper angle of tapered shaft
  • Poor cylindricality of shaft
  • Interference with bearing chamfer due to a large shaft corner radius
  • Correct the interference
  • Check the load conditions
  • Improve the mounting method
  • Use an appropriate shaft shape

 

Click a photo to enlarge it

Cracks 1

Part: Outer ring of a double-row cylindrical roller bearing
Symptom: Thermal cracks occur on the outer ring side face
Cause: Abnormal heat generation due to contact sliding

Cracks 2

Part: Roller of a tapered roller thrust bearing
Symptom: Thermal cracks occur at large end face of roller
Cause: Heat generation due to sliding with the inner ring rib under poor lubrication

Cracks 3

Part: Outer ring of a double-row cylindrical roller bearing
Symptoms: Cracks propagated outward in the axial and circumferential directions from the Flaking origin on the raceway surface
Cause: Flaking from a flaw due to shock

Cracks 4

Part: Outer ring of a double-row cylindrical roller bearing used for outer ring rolling (Outer ring rotation)
Symptom: Cracks on outside surface
Cause: Flat Wear and heat generation due to non-rotation of the outer ring

Cracks 5

Part: Raceway surface of outer ring of damage “Cracks 4”
Symptom: Outside surface crack propagating to the raceway

Cracks 6

Part: Inner ring of a spherical roller bearing
Symptom: Axial Cracks on raceway surface
Cause: Large fitting stress due to temperature difference between shaft and inner ring

Cracks 7

Part: Cross section of cracked inner ring of damage “Cracks 6”
Symptom: Origin is directly beneath the raceway surface

Cracks 8

Part: Roller of a spherical roller bearing
Symptom: Axial Cracks on rolling surface

Downloads

Cookies on the NSK website

We use cookies to ensure that we give you the best experience on our websites and web applications. By continuing without changing your browser settings, we assume you give your consent to receive cookies. However, you can change your browser cookie setting at any time.