What is a typical bearing failure mode in high-speed spindle applications?

• A. Lubrication failure, overheating, and fatigue leading to spalling
• B. Corrosion only
• C. Excess bending
• D. Seal leakage only

Answer: (A)

In high-speed spindle bearings, a common and characteristic failure path starts with lubrication failure. When the lubricant film breaks down, there isn’t enough separation between bearing surfaces, which raises friction and causes a rapid rise in temperature. That overheating accelerates wear and stresses the material, pushing the bearing into fatigue as the cyclic loads fight against the degraded surface. Over time, this fatigue manifests as spalling—flaking or chipping of material from the raceways or rolling elements.

Other options don’t capture this typical sequence. Corrosion alone isn’t the primary failure mode in well-lubricated, controlled spindle environments. Excess bending points to external loading or misalignment rather than a automatic high-speed wear progression inside the bearing. Seal leakage can contribute to lubrication loss, but on its own it doesn’t describe the common progressive path that leads to spalling through lubrication failure and fatigue.