a. Rotor and crankcase cleaning: when the coil of the cooling tower motor burns out, it will release a lot of small acidic substances. The main attachments of these substances are the inner surfaces of the stator, rotor and machine parts, some of which dissolve in the crankshaft of the freezer fuel tank. Therefore, at the beginning of maintenance, these parts must be thoroughly cleaned and all refrigerating oil must be replaced.
b. Clean stator core: After removing the windings, the manufacturer of the cooling tower motor says that the stator core should be carefully cleaned using carbon tetrachloride or gasoline. After washing, you need to wipe and blow dry. Otherwise, the stator iron will remain. Acid freezing oil on the core can also cause some corrosion to the coils newly installed on the core. In addition, once the coil comes into contact with an oily substance, the step of impregnating the insulating varnish will be unsatisfactory, resulting in maintenance failure.
Remove the motor outer oil seal and motor end cover with puller. Pay attention not to damage the stator coil of the motor, and remove the bearing with puller. Clean the inner and outer oil seals. Install the inner oil seal, install the bearing, oil the bearing and the inner oil seal, and install the motor end cover. At this time, pay attention to use a thin copper wire to pierce the screw hole of the inner oil seal out of the motor end cover hole, so as to prevent the screws of the outer oil seal and the inner oil seal from mismatching. Tighten the motor end cover and install the outer oil seal. When tightening, evenly apply force and install the opposite wheel. Turn the motor, there should be no resistance.