ML
To estimate the rolling-element bearing core tempera-
ture, add 15-20 degrees F to the bearing housing or
casing temperature from heat gun inspections. However,
this internal bearing temperature may be 30-50 degrees
F hotter, as infl uenced by ambient cooling conditions,
lubricant circulation, metallurgy, bearing confi guration
and heat generation factors (such as grease churning and/
or high mechanical friction).
For rolling-element bearings running at temperatures
higher than 70 degrees C, cut the bearing life by 1.5 (i.e.,
divide by 1.5) for each increment of 10 degrees C above
70 degrees C.
For circulating oil, there should not be a diff erence
of more than 50 degrees F between the oil going in and
coming out of the bearing.
Core Temperature
Surface
Temperature
Bearing Temperature Inspections
Core Temperature
Surface
Temper
