(1) Water pump shaft bending or different center, will make the pump vibration, cause bearing heating or wear.

(2) Due to the increase of axial thrust (such as when the balance plate and balance ring in the water pump are seriously damaged), the axial load borne by the bearing is increased, leading to the bearing heating or even damage.

(3) the amount of lubricating oil (fat) in the bearing is insufficient or excessive, the quality is poor, and there are impurities such as sediment and iron filings; Sliding bearing sometimes because the oil ring does not rotate, with no oil to cause bearing heat.

(4) bearing fit clearance does not meet the requirements. Such as the bearing inner ring and the pump shaft, the bearing outer ring and the bearing body, with too loose or too tight, can cause bearing heating. (Too tight will make the bearing rotation inflexible; If the match is too loose, the inner ring of the bearing will rotate or the whole bearing will rotate in the bearing body).

(5) the static balance of the pump rotor is not good. Pump rotor radial force increases, bearing load increases, resulting in bearing heat.

(6) The vibration of the pump when the pump is operating in the non-design point condition will also make the pump bearing hot.

(7) The bearing has been damaged (including the quality problem of the purchased bearing itself), which is often the common reason for bearing heating, such as rolling bearing cage damage, steel ball crushing inner ring or outer ring fracture; Sliding bearing alloy layer peeling, block, etc. In this case, the sound of the bearing is abnormal and the noise is large. The bearing should be disassembled in time to check and replace it