Bearing seizure is most directly caused by which of the following during operation?

Bearing seizure is most directly caused by which of the following during operation?

• A. Excessive heat during rotation causing elements to soften.
• B. Bearing weight.
• C. Inadequate lubrication without heat.
• D. Overcooling.

Answer: (A)

Excessive heat during rotation is what drives a bearing to seize. When heat gets too high, bearing elements can soften and lose hardness, causing the clearances to collapse and the surfaces to grip or weld together. That adhesion locks the bearing and stops rotation. Weight or load alone doesn’t directly cause a seizure, and lacking lubrication without heat isn’t the exact mechanism—the heat is what creates the conditions for the surfaces to seize. Overcooling isn’t a seizure cause either; it doesn’t promote the metal-to-metal bonding that leads to locking.

Excessive heat during rotation is what drives a bearing to seize. When heat gets too high, bearing elements can soften and lose hardness, causing the clearances to collapse and the surfaces to grip or weld together. That adhesion locks the bearing and stops rotation. Weight or load alone doesn’t directly cause a seizure, and lacking lubrication without heat isn’t the exact mechanism—the heat is what creates the conditions for the surfaces to seize. Overcooling isn’t a seizure cause either; it doesn’t promote the metal-to-metal bonding that leads to locking.