Repair of common faults of grain flour machine
(1) When the bearings are worn, some can be repaired by welding. For example, when the bearing runs the inner and outer rings, use electric welding to stop the surfacing of the shaft journal and the inner hole of the end cover, and then use a lathe to process it to the required size. Preheat the shaft and the inner hole of the end cover (150-250℃) before welding. The shaft generally uses J507Fe welding rod, and the inner hole of the end cover always uses common cast iron welding rod. When the welding is completed, immediately bury it deeply in dry lime powder and cool slowly to control the phenomenon of rapid cold brittleness. When turning and repairing permanent welding, pay attention to: ①The concentricity correction value is not greater than 0.015mm to avoid high-speed running noise and vibration heating during eccentricity, which will shorten the service life of the motor; ②When the motor journal is less than 40mm, 6-8 should be adopted. For the method of equal-part line surfacing, the full surfacing method should be adopted for the journal >40mm. This is determined by the amount of force transmitted by the shaft when outputting power. Regardless of the surfacing method, pay attention to the use of intermittent strips and symmetrical welding to prevent part of the welding stress from being too high and the first question being too high, resulting in greater changes in the concentricity of the shaft. ③In lathe processing, the turning roughness of the motor shaft below 11KW is controlled to about 3.2. After the 11KW motor shaft and the end cover hole are turned, the grinding machine is used for finishing to ensure the quality.
(2) When the rotor is separated from the shaft, first use high-temperature resistant 502 adhesive to stop filling the gap between the restored rotor and the shaft. The part to be filled should be placed vertically and the movement should be rapid. After the two ends are injected and irrigated, they are re-irrigated with 40% salt water. After a few days, they can be assembled and used.