How to Repair Transformer Cooling Units?

How to Repair Transformer Cooling Units?

1. Repair of radiator
Radiator is one of the main components of transformer leakage, so the repair of radiator to deal with leakage defects as the main content. At the same time, the radiator should also be cleaned to prevent the impurities inside the radiator with the oil flow into the transformer internal fault. In addition, clean the outside of the radiator to improve its heat dissipation effect.

 

2. Maintenance of fan motor
Fan motor is in the operation of wind, rain, sun and dust conditions, so there are more chances of failure, the common failure is due to rain cover, lead end cover seal is not good and water, so that the insulation level is reduced, so that the winding burned; There are also single-phase operation caused by improper protection will burn the winding, long running time, lubricating oil deterioration in the bearing, so that the wear is serious, in addition to some other failures.
The fan motor should be disassembled and overhauled during maintenance. Before the fan motor is removed from the transformer, the power cord should be removed first, and then the fan blade should be removed to avoid damaging the fan blade and changing the Angle of the fan blade. Then, the fixing bolt should be unscrewed. The steps of disassembling the motor are as follows:

 

2.1 Remove the screws of the bearing end cover and the small sealing cover, remove the fixing screws of the two end covers and the frame, and then gently strike the two end covers with a hammer to remove the end covers. If the bearing is loose, the bearing can be removed; After disintegration, if the winding is damaged, the winding should be replaced according to the maintenance steps of general motors. If the bearing is damaged, a new bearing should be applied. Then use a flat shovel to clean up the paint film and dirt at the stop of the shell and two end covers. Brush the bearing seat of the two end covers and the shaft head of the rotor end with a brush and gasoline. Other parts have to be cleaned before they can be assembled. The assembled fan motor shaft should be flexible and frictionless by hand, and the fan motor should be installed in the original position after maintenance.

 

2.2 The fan motor after maintenance shall do electrical test, measure winding insulation resistance and motor no-load test, and put into operation after passing the test.

 

3. Maintenance of moisture absorbent
3.1 Remove the hygroscopic device from the transformer connecting pipe, then unscrew the bottom cover first, release the transformer oil, unscrew the nut on the middle fastening screw, and remove the base and glass tube. If the silicone has turned pink, it indicates that it has failed, and the silicone is poured away.

 

3.2 Check whether the upper flange and connecting pipe are ventilated. If they are not ventilated, they should be treated to ensure a smooth air passage. Otherwise the hygroscope will not be able to breathe. After disintegration, clean up the parts, replace the rubber pads, and then reinstall them, replace them with new discolored silicone, and do not tighten too hard to prevent the glass tube from being tight.

 

3.3 The bottom cover should be filled with an appropriate amount of transformer oil as the oil seal.