Common faults and solutions of transformer
Writer： Hengfeng you electric Time：2023-04-19 views：times
Generally, the service life of power transformer is 15-20 years, but due to human or environmental factors, some common faults will occur in the use of transformer. How to solve these faults? The following are the common fault causes and solutions of transformer:
1. Oil leakage at welds
It is mainly due to poor welding quality, false welding, desoldering, pinholes, sand holes and other defects in the weld. When the power transformer leaves the factory, the hidden dangers are exposed after operation due to the coverage of welding flux and paint. In addition, the electromagnetic vibration will crack the welding and cause leakage. If leakage has occurred, find out the leakage point first and do not omit it. For the parts with serious leakage, metal tools such as flat shovel or sharp punch can be used to rivet the leakage point. After controlling the leakage, the treatment surface can be cleaned. Most of them are cured with polymer composites. After curing, the purpose of long-term treatment of leakage can be achieved.
2. Seal oil leakage
Reasons for poor sealing: generally, the sealing between the box edge and the box cover is sealed with oil resistant rubber rod or rubber gasket. If the joint is not handled well, oil leakage will be caused. Some are bound with plastic tape, and some directly press the two ends together. Due to rolling during installation, the interface can not be pressed firmly, which can not play a sealing role, and it is still oil leakage. Fushi blue material can be used for bonding to form a whole joint and greatly control the oil leakage; If the operation is convenient, the metal shell can also be bonded at the same time to achieve the purpose of leakage treatment.
3. Oil leakage at flange connection
The flange surface is uneven, the fastening bolts are loose, and the installation process is incorrect, so that the bolts are not fastened well, resulting in oil leakage. After fastening the loose bolts, the flange shall be sealed, and the bolts that may leak shall also be treated to achieve the purpose of complete treatment. Tighten the loose bolts in strict accordance with the operation process.
4. Oil leakage of bolt or pipe thread
When leaving the factory, the processing is rough and the sealing is poor. The oil leakage fault occurs after the power transformer is sealed for a period of time. The bolts are sealed with polymer materials to achieve the purpose of controlling leakage. Another method is to screw out the bolt (nut), apply Fushi blue release agent on the surface, and then fasten it after applying materials on the surface. After curing, the treatment purpose can be achieved.
5. Oil leakage of iron castings
Oil leakage is mainly caused by sand holes and cracks in cast iron castings. For crack leakage, drilling crack stop hole is a method to eliminate stress and avoid extension. During treatment, lead wires can be driven into the leakage points or riveted with a hammer according to the crack conditions. Then clean the leakage point with acetone and seal it with materials. Cast sand holes can be directly sealed with materials.
6. Radiator oil leakage
The heat dissipation pipe of the radiator is usually made by stamping after flattening with slotted steel pipe. Oil leakage often occurs in the bending part and welding part of the heat dissipation pipe, because when stamping the heat dissipation pipe, the outer wall of the pipe is under tension, and its inner wall is under pressure, resulting in residual stress. Close the upper and lower plate valves (butterfly valves) of the radiator to isolate the oil in the radiator from the oil in the box and reduce the pressure and leakage. After the leakage position is determined, appropriate surface treatment shall be carried out, and then Fushi blue material shall be used for sealing treatment.
7. Oil leakage of porcelain bottle and glass oil standard
Usually due to improper installation or seal failure. Polymer composites can bond metals, ceramics, glass and other materials well, so as to achieve the fundamental treatment of oil leakage
