AXLE-REAR
MOTOR TRUCK SERVICE MANUAL
Fig. 22 - Ball Bearing Inner Race Marked From False Brinelling.
False brinelling resulting from vibration without relative
inner and outer races. Exposure of the bearing surface
rotation of the inner and outer races, Fig. 22. With the
to air will oxidize the microscopic metal particles freed by
inner and outer races stationary and the entire bearing
the vibrating movement. These oxides in turn form an
subject to vibration, the balls will rotate and indent the
abrasive which deepens the indentation further.
Fig. 23 - Ball Depressions Produced By an Off-Center Blow in Mounting.
True brinelling is caused by an off-center blow during the
ion frequently go unnoticed in operation because the load
mounting process. In the example shown, only three
does not cause the ball path to reach the brinell marks on
balls produced depressions, Fig. 23. Shallower marks
the edges of the races. The balls, however, acquire
frequently go unnoticed because the edges of the
similar depressions and will make the bearing sound
brinelled depression are not clearly marked and no
noisy or "catchy" as if it had several small pieces of
change appears in the surface of the raceway. Brinell
foreign material lodged in it. Failure of the bearing may
marks of this nature are difficult to see under a
result because of the flat spots on the balls or on the
microscope.
Bearings marked in this fash
races.
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