Many gears are often driven in one direction, thus causing unilateral wear. When the structure is completely symmetrical, directly turn to 180. It can be used after installation. If it is asymmetric, the gear can be annealed first, then the asymmetric part is cut and welded to the other side of the gear, and then the gear is heat treated.
For gears with small load and low speed, when individual teeth are seriously damaged, the root of bad teeth can be processed into trapezoidal grooves on milling machine or planer, and the gear blank can be pressed into the grooves with certain tightness, then welded or fastened with pins, and finally the correct tooth profile can be repaired on milling machine with forming milling cutter.
To replace the gear ring, first anneal the gear, close all the gear teeth, then press a gear ring, then fasten it with welding or pins, and finally carry out heat treatment.
Plastic deformation method: after the gear is heated to 800-900℃, it is put into a tooth mould to produce plastic deformation, and the metal in other parts is extruded to the worn surface of the gear, and then heat treatment is carried out after shaping.
Grind the cracked part of gear teeth with a fine grinding wheel to remove the incomplete fatigue layer, and then repair it by surfacing. When welding and repairing, the gear should be immersed in water and then annealed first. For carburized steel gears, 20 or 45 steel wire can be used for gas welding, or low hydrogen covered electrode can be used for repair. After welding, the tooth profile should be trimmed by machining or manual template, and finally it should be reheated and polished with oilstone or abrasive.
Cracks in rims, spokes and hubs can be repaired by welding, riveting and bonding.