Hefei underground cable well pipe plugging

Blocking of underground cable shafts has always been a headache for power engineering. Assuming that there is one cable in the cable duct, the underground cable pipe is generally a PVC pipe. The accumulated water in the well is caused by rainwater or the road surface has penetrated into it. However, since there is no drainage channel designed, it is not easy to evaporate. The water level will exceed the height of the cable duct. If the pipeline is not blocked, the electric underground wells on both sides will share the water level, and the cable will always be immersed in the water. When one of the underground wells is opened for cable maintenance and management, the accumulated water in the underground well must be extracted first, but due to the shared water level, it is equivalent to simultaneously extracting the accumulated water in the underground well with the current connected power within a certain range. Pumping stagnant water makes the water level of the stagnant water lower than the height of the cable duct to be maintained. However, because the cable ducts are connected, the water in the adjacent power underground well will flow into the low water level through the cable duct when the water from the underground well to be maintained is drawn. The section has reached the water level balance. Therefore, the cost of maintaining the electric underground well without being blocked will be inestimable. Once the emergency repair situation occurs, the race against time will increase the difficulty of the emergency repair work.

The traditional plugging of cement, foam, and fire-resistant mud is only a temporary emergency plugging, and it fails to prevent the problems caused by stagnant water and water, and even some harmful cables cause greater trouble to cable maintenance. At this stage, the inflatable cable duct sealing device can seal the cable duct opening very well, but the effect required to block the cable duct is not very satisfactory due to the limitation of its product function (see IDSS product comparison article for details)

The following example is a field photo taken by Hangzhou Hengma Electric Power Technology Co., Ltd. when an underground well is blocked in Hefei Power. In the photo, the cable duct has been damaged and the water level has risen to a low cable duct mouth.