The most common causes of _________ _______ include improper seating, bearing misalignment, poor installation, vibration due to imbalance, and passage of electric current through the bearing.

• A. bearing wear
• B. bearing failure
• C. bearing damage
• D. seal leakage

Answer: (B)

Bearing failure is typically the result of abnormal or excessive loading and electrical damage. When a bearing is not seated properly or is misaligned, the loads on the races and rollers become uneven or off-axis, causing edge loading, accelerated wear, and fatigue that can lead to failure. Poor installation can compromise preload and lubrication, increasing friction and stress on the bearing surfaces. Imbalance-induced vibration subjects the bearing to cyclic forces beyond its design limits, driving fatigue cracks and spalling. The passage of electric current through the bearing creates electrical erosion, pitting, and surface damage that rapidly undermines bearing integrity. These interconnected mechanisms explain why this set of causes is most closely associated with bearing failure, rather than merely wear, general damage, or seal leakage.