The method of rotor repair is a technology that machinery industry personnel must master. Common rotor repairs include generator rotors, which are the rotating parts of generators. It is mainly composed of conductive rotor winding, magnetic core, rotor shaft extension, guard ring, center ring and fan. So what are the methods of repairing the generator rotor? In fact, it is mainly the repair of the insulating part and the metal part, please see the detailed introduction below!

1. Repair of insulation parts

(1) The burn length of the groove insulation is 50 mm from the axial direction of the groove. Lay down the copper slot wedge, shave the charred insulating part with a knife, and remove the carbon on it, then clean it with carbon tetrachloride, and then use the phenolic glass cloth to cut the material according to the corresponding standard requirements, and use phenolic insulation. paint to bond. It should be noted that: a total of 7 slots are repaired on the exciter side, and a total of 10 slots are repaired on the steam turbine side.

(2) Since all the insulating tiles under the retaining ring were damaged, it was decided to remake them. We can use 0.5~1.5 mm thick cyclophenolic glass cloth, and cut the material according to the requirements of its size. It should be noted that the lap joints of each layer must be separated and staggered, and the layers are bonded with epoxy resin. After the insulating tile is finished, we can use a mold that is 0.8 mm larger than the inner diameter of the retaining ring and has a similar taper to press the insulating tile until the adhesive is cured. At this time, we need to pay attention to the supporting force of the mold, so that the insulating tile does not deform due to its own weight sagging. According to the drawings, we can drill 8mm holes in the insulating shoe and the coil spacer, and then insert the insulating pin, so that the rotor end spacer and the insulating shoe are positioned. It is also necessary to avoid displacement of the insulating tiles during installation and operation, and there should be 8 pin holes for each end of the insulation. The ventilation holes on the insulating tile can be drilled according to the space orientation of the end coil and the drawing requirements.

2. Repair of metal parts

(1) The generator rotor teeth and copper wedges are damaged on the embedded surface. There is a large area of ​​unevenness in the embedded surface of the copper slot wedge. At this time, we should replace the damaged part, that is, remove all the original embedded surface, reduce the length of the steel wedge by 25 mm, move the copper orange wedge to both ends, and use a 25 mm long LC-4 type hard wedge in the middle. Aluminium pile wedges are added. Roughly shape the part of the embedded surface of the copper slot wedge, and leave a margin of 1 mm. After the copper slot wedge is installed in the rotor slot, it is installed on the surface together with the rotor teeth, and the damage marks of the rotor teeth are removed. Due to the lack of large lathes, we can hoist the motor stator, use the electric turning car to load the plate and move the rotor to change, and then install the tool holder for rough turning, and then use the high-speed fine grinding wheel to grind until the gloss of the embedded surface reaches 3-6 stagnation. . The taper of the embedded surface is required to be no more than 0.03 mm, and the ovality is no more than 0.06 mm.

(2) The embedded surfaces of the retaining rings on both sides have severe damage and multiple cracks. However, the two retaining ring blanks that have been found so far have been roughed on the inner and outer surfaces of the retaining ring, and have been found to have different levels of failure through ultrasonic flaw detection and metallographic inspection. They are not two completely qualified spare parts, and only one section of each can be used. Therefore, it was finally decided to use the method of splicing the old and new two-section retaining rings that have been used at home and abroad to repair the original retaining ring.

The above is the method of repairing the generator rotor, mainly to repair two parts: one is the insulating part, and the other is the metal part. Because once the generator rotor fails, the two parts are more likely to be damaged, so the repair personnel should master the repair method of the generator rotor, so that the generator rotor can work better and achieve higher work efficiency .