Fatigue dimples in rolling bearings due to excessive static loads are similar to dimples caused by foreign particles, and their raised edges can lead to failure. Phenomenon: In the initial stage, the pits distributed with the rolling element spacing are often only distributed on part of the circumference, which eventually leads to the appearance of cracks. This sometimes happens with only one ferrule. Often asymmetrical to the center of the raceway. Causes: – Excessive static loads, shock loads – Mounting forces transmitted through the rolling elements Remedy: – Follow the installation instructions – Avoid overloads and excessive shock loads Fatigue phenomena due to incorrect mounting: For angular contact ball bearings In general, there is fatigue in the non-contact area near the small rib, see Figure 46. Causes: – Improper adjustment – ​​Insufficient axial contact or locking bolts not tightened – Too much radial interference Remedy: – Ensure rigidity of surrounding components – Correct installation Fatigue due to misalignment: – Track off-centre of bearing , see Fig. 40 – Fatigue on raceway/rolling element edges, see Fig. 47 – Circumferential grooves caused by plastic deformation on the whole or part of the surface, so the edges are smooth. In extreme cases, there will be cracks in the bottom of the groove, see Figure 48.

  Cause: Due to misalignment of the housing or deflection of the shaft, the inner ring is tilted relative to the outer ring and causes large moment loads. For ball bearings, this results in forces in the cage pockets (section 3.5.4), more sliding on the raceways and the balls running on the edges of the raceways. For roller bearings, the raceway is asymmetrically loaded. When the ring is seriously inclined, the edge of the raceway and the rolling elements will bear the load, and stress concentration will occur. Please refer to “Misalignment track” in chapter 3.3.1.2. Remedial measures: – Use self-aligning bearings – Reduce misalignment – ​​Improve shaft strength 31 Evaluate running characteristics and damage of removed bearings fatigue. 48: Fatigue occurs at the edge of the ball bearing raceway, such as with high moment loads (edge ​​running); the left picture shows the edge of the raceway, and the right picture shows the ball.