Where does anti-friction bearing fatigue failure usually begin?

Anti-friction bearing fatigue failure typically begins from micro cracking. This phenomenon occurs due to the repetitive stress cycles that the bearing materials endure during operation. Over time, fatigue initiates small cracks, known as micro cracks, in the raceways and rolling elements of the bearing. These micro cracks can develop due to factors such as improper alignment, excessive loads, or inadequate lubrication. As these cracks propagate, they can lead to larger surface failures, compromising the integrity of the bearing and ultimately leading to its premature failure.

The other potential origins of fatigue failure, such as from the outer race or the bearing housing, while relevant to overall bearing performance, are typically not where the fatigue process itself initiates. Similarly, the lubrication surface plays a critical role in reducing wear and friction, but it does not initiate the fatigue cracks. Understanding the micro crack formation and development is crucial for both predictive maintenance and proper troubleshooting in bearing applications.