What is the primary cause of excessive wear on bearings in a system?

The primary cause of excessive wear on bearings in a system is misalignment. When bearings are misaligned, the load distribution is uneven, causing excessive stress on specific areas of the bearing surfaces. This misalignment can lead to increased friction and heat generation, which in turn accelerates wear and can result in premature failure. Proper alignment is crucial for ensuring that bearings operate smoothly and efficiently, minimizing wear and extending their lifespan.

The other options may contribute to bearing issues, but they are not as directly impactful on wear as misalignment. For example, while reduced oil due to low viscosity can lead to lubrication problems, it primarily affects performance rather than directly causing wear. A blown seal may result in lubricant leakage or contamination, but again, this is more a concern for the operation rather than direct wear from misalignment. Over tubercation generally refers to an advanced wear mode resulting from metal fatigue, which is also less prevalent than the immediate effects of misalignment.