When removing and installing the rotor of aluminum motor shell, attention should be paid not to damage the iron core and stator winding. Before pulling out the rotor, the air gap under the rotor and winding end should be padded with thick cardboard to avoid damaging the iron core and winding when the rotor is pulled out. Disassembly of the rotor of variable speed motor for small aluminum case. For the rotor less than 30kg, it can be directly pulled out by hand. Hold one end of the rotor with both hands, pull out the rotor with one hand, and support the rotor core with the other hand, and gradually move out. Disassembly of large aluminum shell variable speed motor rotor. For large aluminum shell variable-speed motor, if both ends of the rotor are extended out of the frame part long enough, lift it out with lifting equipment. However, attention should be paid to the protection of journal, stator winding and rotor core air duct during lifting. For the motor whose rotor shaft extends out of the frame for a short time, a steel pipe can be set at one end or both ends of the rotor shaft, and a steel pipe is set on the left side of the rotor of the aluminum shell variable speed motor, and then the rotor is lifted out in two steps. The mechanical equipment for lifting can be crane, such as manual hoist. The method of rotor installation is opposite to that of steps and rotor removal, but attention should be paid to the protection of all parts of aluminum housing variable speed motor.