How to repair the end cover of the motor?
The end caps of the motor are mostly made of cast iron, which serves to support the rotation of the rotor of the motor and protect the ends of the coil. Common faults of the motor end cover are the end cover rupture, the end cover stop loose, the end cover stop damage, the gap between the end cover bearing hole and the bearing is increased, and the repair method is briefly described as follows.
(1) End cap rupture
When there is a serious crack in the end cap, if there are casting and machining conditions, the new end cap should be cast. If it is not possible to cast a new end cap due to conditions, it can be repaired by means of electric welding, brazing and adhesive bonding depending on the degree of cracking.
In the case of electric welding or brazing, in order to prevent the end cap crack from extending during welding, if the crack is in the middle of the plane, a hole having a diameter of 2.5 to 3 mm may be drilled on both sides of the crack; if the crack is split from the edge of the end cap toward the axial hole A hole with a diameter of 2.5 to 3 mm can be drilled at the end of the crack. Then use a sharp chisel to remove the groove at the crack and heat the end cap to 180-250 ° C, which can be welded with cast iron welding rod. When welding with a copper electrode, the end cover does not need to be preheated, and it can be directly welded with a copper electrode. In order to prevent the occurrence of new cracks, the welding is completed, and the weld is insulated with charcoal powder or straw ash to allow it to cool slowly. After cooling, check the end cap for deformation and machine the mating surface of the end cap to the original size and roughness.
When there is no welding condition and the end cap is urgently needed for production, or if the crack is not suitable for welding, it can be repaired by riveting or bolt fastening depending on the crack or crack degree of the end cap. When repairing, cut the steel plate with appropriate size and thickness of 5~8mm according to the crack shape, and drill the corresponding holes on the steel plate and the end cover respectively, then rive the steel plate with the end cover with rivets, or fix the steel plate at the end with bolts. Covered to enhance the mechanical strength reduced by cracks.
Adhesive bonding can be used when neither welding conditions nor riveting or bolting conditions are available. Before sticking, in order to prevent crack propagation, first drill holes at the beginning and end of the crack. Then use a pair of tweezers to remove the 60° V-shaped groove along the crack to the stop hole at both ends. The V-groove depth is about 50% of the thickness of the end cap. Then wipe the bonding surface of the tank with a cotton swab dipped in acetone. The iron anchor 101 and B two-component polyurethane glue were evenly stirred in a glass vessel at a volume ratio of 2:1, filled with a V-shaped groove, and scraped with a spatula. The end caps were placed in an oven and baked at 100 ° C for 2 h to completely cure the adhesive. Once the adhesive is cured, the end caps can be assembled.
(2) The end cap is loose
The tightness of the end cover and the base is directly related to the normal operation of the motor, and the maximum clearance allowed between them.
When the end cap is loose, the mouth is usually fastened by electroplating.
(3) End cover bearing hole and bearing clearance increase
When the end cap bearing hole and the bearing clearance and the specified value exceed 0.05 mm, the rotor and the stator of the motor are rubbed. At this time, one is to remove a part of the end bearing hole on the lathe, then turn a suitable sleeve into the original bearing hole size; in addition, it can also be plated on the inner surface of the worn bearing hole. Nickel, returning the bearing bore to its original size.
(4) End cap damage
When the surface of the end cap is damaged and there is dirt, the scraper can be scraped off with a scraper, and then the flaw is smoothed with a trowel and a stone, and then the oil can be applied.
