What is the cause of damp underground power cables?

Qingzhou cable manufacturer summarizes the reasons why underground power cables are damp?

Qingzhou cable manufacturer summarizes the reasons why underground power cables are damp?

What is the cause of damp underground power cables? The staff of the cable factory will introduce it to you here.

1. After the completion of underground cable laying, due to the limitation of on-site construction conditions, the cable head is not made in time, so that the cable fracture without sealing treatment is exposed to the air for a long time, or even immersed in water, so that a large amount of water vapor enters the cable.

2. During cable laying, it is necessary to often cross roads, bridges and culverts. Due to weather or other reasons, a lot of water is often accumulated in the cable trench. During the laying process, it is inevitable that the cable head will be immersed in the water, and the water will enter the cable due to loose wrapping or damage of plastic cloth; In addition, when pulling and threading pipes, sometimes the outer sheath or even steel armor will be scratched, especially when mechanical traction is used.

3. When the whole incoming cable leaves the factory, its two ends are sealed with plastic sealing sleeves. However, after a section is used at the construction site according to the actual situation, the rest is simply wrapped with plastic cloth. Because it is usually placed in the open air and the sealing is not good, water vapor will inevitably penetrate into the cable over a long period of time.

4. During the normal operation of the UD cable, if breakdown and other faults occur for some reason, the ponding in the cable trench will enter the cable along the fault point; In civil construction, especially in the construction site where large construction machinery is used, cable damage or breakdown accidents caused by various human factors are also common. In case of such an accident, the cable insulation will be seriously damaged and water will also enter the cable.

5. During the fabrication of cable head (including terminal head and intermediate joint), due to the negligence of construction personnel, the newly treated cable head sometimes accidentally falls into the ponding on the site.