The cause of construction quality
Because of the construction quality, there are many cases of high voltage cable system failure. The main reasons are as follows: one is that the conditions of the field are very poor, the environment and the technological requirements of the cable and joint in the factory are very high, and the temperature, humidity and dust of the construction site are not well controlled. Two is the cable construction process in the insulation surface will inevitably leave small slippery marks, semi conductive particles and sand cloth on the sand may also be embedded in the insulation, in addition to the joint construction process, insulation exposure in the air, insulation will also breathe water, which leave hidden dangers for long-term safe operation. Three, installation is not strictly considered according to process construction or process regulations. The four is the completion acceptance. The DC voltage withstand test results in the formation of the anti electric field in the joint, resulting in insulation failure. The five is caused by poor sealing treatment. The intermediate joint must adopt the metal copper shell and the sealing structure of the PE or PVC insulation anticorrosion layer, and ensure the sealing of the seal in the field construction, so as to ensure the sealing and waterproof performance of the joint effectively.