INA imported bearing inspection mainly has the following points

1) The quality of the INA bearing imports. During the collapse of the bearing box, first of all, check whether lubricating grease are deteriorating, agglomerate, impurities such as adverse situation, it is the important basis of judging INA bearing damage reason. Second, check the bearing have chewed and wear; Check the INA bearing inner and outer ring, rolling body, maintains its surface finish and presence of cracks, rust, discoloration defects such as peeling, pits, overheating, excessive measuring INA bearing clearance; Check whether there is any wear and tear on collar, pit point, peeling, if has the above situation should change new INA bearings. 2) INA import bearings. Bearing installation bearing inside diameter and shaft, with the outer diameter and the shell is very important, when cooperate with too loose, mating surface will produce relatively sliding known as creep. Once produced to wear matching surface, creep damage of shaft or housing, and wear into the INA bearing internal powder and fever, vibration and damage. Interference is too big, can lead to small outer diameter or inner circle diameter, reducing the INA bearing internal clearance. To choose the suitable for use with, want to consider the nature of bearing load, size, temperature condition, the rotation of the inner ring outer condition factors. 3) INA bearings imported parts fit clearance adjustment. INA bearing clearance after hours, due to the shear friction loss in oil in the gap is too big, can also cause bearing heating, at the same time, the clearance after hours, oil amount decreased, too late to take away the heat generated by the friction, will further improve the INA bearing temperature rise. But the gap is too large will change characteristics of INA bearings, rotor caused by unstable operation. So the need for different devices and conditions of use select verify INA bearing clearance. Guohua taicang unit # 8 B long bearing temperature on the high side problems existing in the induced draft fan, the c-class overhaul of unit in 2008, the examination of the key for this problem. Examination revealed INA bearing lubrication, impeller static balance, coupling are all normal, the screen to focus on INA bearings by clearance. Measured thrust bearing clearance is only 0. 7 mm, this paper analyzes the reasons of gap is too small for thrust bearing temperature on the high side. With the grinding machine of the thrust bearing ring grinding 0. 7 ~ 0. 8 mm, expand the thrust clearance, make the INA bearing thrust gap widened to 0. 14 ~ 0. INA bearing in the operation of the 15 mm, in normal temperature, eliminate the defects of the long-term legacy to ensure the safe and stable operation of the equipment. Yunnan phosphorus electric INA bearing temperature is too high for a long time, induced draft fan for # 1 unit of 80 ~ 90 ℃, cause the bearing service life shortens greatly, replacement of INA bearings failed to solve the problem for many times. In 2008 C level maintenance, inspection found that the gap between shaft and the shaft seal end cover is too small, bearing temperature is normal, when cold running in hot runtime axial thermal expansion, and the friction of the end cover seal. Analyses the reason of this is INA bearing high temperature for a long time, turning the end cover port 0. 5 mm, shaft and the end cover of the shaft sealing gap expanded 0. 25 mm, avoid running after the axial thermal expansion and the end cover friction. After processing, the problem of INA bearings temperature is too high to get the basic improvement, cold and hot state in the operation of the bearing temperature is normal, and the bearing box does not appear oil leakage phenomenon, ensure the INA bearing good running conditions, reduced the INA bearing replacement frequency, save the maintenance cost.