NTN bearing overheat reasons of common failures

NTN bearing fault phenomenon generally show the two kinds, one is bearing installation site temperature is too high, the second is the bearing running noise. Installed in institutions, there is the part of the rolling bearing a certain temperature, when the hand touch body shell, should not feel hot as normal, conversely indicates that bearing temperature is too high. The cause of the high bearing temperature are: lubricating oil quality does not conform to the requirements or metamorphism, lubricating oil viscosity is too high; The assemble tight ( Inadequate clearance) ; Rolling bearing assembly too tight; Bearing race in internal rotation shaft or housing; Too much load; Bearing cage or NTN body fracture, etc. NTN bearing allows running noise slightly in the work, if you have any abnormal noise or excessive noise or sound, suggests that the bearing failure. NTN bearing causes of noise is more complex, one is the bearing inner and outer surface wear. Due to the wear and tear, damage and shell, rolling bearing and the bearing axis of cooperate relationship, lead to axis deviation from the correct position, when axis at high speed movement produces sound. When the bearing fatigue, its surface metal flake, also can produce sound make bearing radial clearance increases. In addition, the bearing lubrication, forms the dry friction, and bearing broken etc all make abnormal noise. Bearing wear loose after kuang, maintains a looseness damage, also can produce sound. ( 1) NTN bearing damaged, should be replaced immediately. ( 2) NTN bearing grease too little, too much, or has the impurity such as iron filings. Grease bearing capacity should not be more than 70% of the total volume, have impurities should be replaced. ( 3) Shaft and bearing fit too tight or too loose. Should be tight to grinding, must be set to a shaft with too loose. ( 4) NTN bearing and end cover fit too tight or too loose. Too tight when processing the bearing chamber, too loose inside the end cover set steel bushing. ( 5) Two motor end cover or bad bearing cover assembly. Will end cover or bearing cover check into mouth, flat, tighten the screws. ( 6) The belt too tight or bad coupling assembly. Adjust the belt tension, coupling correction. ( 7) Rolling bearing lubricants too little, have impurities or oil ring stuck. Should such as refueling, change new oil, repair or replace the oil ring.