What’s bearing temperature rise?

Almost all friction loss in a bearing is transformed into heat within the bearing itself and causes the temperature
of the bearing to rise.
Bearing operating temperature is determined by the equilibrium or balance between the amount of heat generated by the bearing and the amount of heat conducted away from the bearing. In most cases the temperature rises sharply during initial operation, then increases slowly until it reaches a stable condition and then remains constant. The time it takes to reach this stable state depends on the amount of heat produced, heat capacity/diffusion of the shaft and bearing housing, amount of lubricant and method of lubrication. If the temperature continues to rise and does not become constant, it must be assumed that there is some improper function.

Reference Standard

JB/T 8571 – 2008

Rolling bearings – Sealed deep groove ball bearings – Performance test rule of dustproofing, grease leakage and temperature rise
Note: JB/T means Chinese industrial standard