Autopsy of a "good" IMS bearing

[Walter White]

Originally Posted by Jamesp

Cutting apart the bearing to inspect the inner races revealed a series of equally spaced scuffed lines running across the bearing race. These appeared to be discrete areas of fine pitting on the races. There were 8 lines on the inner race, and 7 lines on the outer race. This is the inner race:

I am speculating that it may be a shock that is sent through the cage when the balls change from being loaded to unloaded. A ball that is under load pushes the cage, and the balls that are not under load are pushed by the cage. Perhaps a shock is sent through the cage each time a ball transitions from loaded to unloaded. This causes the ball to slam from one side of its cell to the other side of the cell. Maybe this creates a shock that travels through the whole cage and affects all the balls at once. Maybe this shock causes the balls to skid for an instant as the cell wall crashes into its ball.

[Jake Raby]

Looking at new, good used and failing bearing surfaces (races and balls) under an electron microscope really tells the story.

These photos are published in my book :-)

[Walter White]

Here is some information I found. Information on this site seems easier to find than most.

Knowledge of Bearings