Hangzhou Henma Power Technology Co., Ltd.

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Sealing of underground cable well pipelines in Hefei


Release time:

2020-02-09

Sealing underground cable wells and pipelines has always been a headache for power engineering. Assuming that there is one cable in the cable duct, the underground cable duct is usually PVC pipe. The accumulated water in the well is infiltrated by rainwater or road surface water, but due to the lack of drainage channels and difficulty in evaporation, the water level will exceed the height of the cable duct after a certain period of time. If no sealing is implemented, the water level will be shared between the two power underground wells when the pipeline is connected, and the cable will always be immersed in water. When one of the underground wells is opened for cable maintenance management, it is necessary to first extract water from the underground wells. However, due to the shared water level, it is equivalent to simultaneously extracting water from the interconnected power underground wells within a certain range. Extracting accumulated water causes the water level to be lower than the height of the cable duct to be maintained. However, due to the interconnectivity of the cable ducts, the accumulated water in the nearby power underground well will flow into the low water level section through the cable duct to achieve water level balance. Therefore, the cost of maintaining the power underground well without sealing cannot be estimated. Once emergency repairs occur, Running against time is even more challenging for emergency repair work. The traditional plugging cement, foam, fireproof mud and other plugging are only temporary emergency plugging, which can not prevent ponding and problems caused by ponding. Some hazardous cables even cause more trouble for cable maintenance. At present, the inflatable cable duct sealing device can effectively seal the cable duct opening, but due to the functional limitations of its product, the required sealing effect is not ideal (see the IDSS product comparison section for details). The following example is a field photo of Hangzhou Hengma Power Technology Co., Ltd. sealing the underground well of Hefei Power. In the photo, the cable duct has been damaged, and the water level has risen to a low position at the cable duct opening.

       Sealing underground cable wells and pipelines has always been a headache for power engineering. Assuming that there is one cable in the cable duct, the underground cable duct is usually PVC pipe. The accumulated water in the well is infiltrated by rainwater or road surface water, but due to the lack of drainage channels and difficulty in evaporation, the water level will exceed the height of the cable duct after a certain period of time. If no sealing is implemented, the water level will be shared between the two power underground wells when the pipeline is connected, and the cable will always be immersed in water. When one of the underground wells is opened for cable maintenance management, it is necessary to first extract water from the underground wells. However, due to the shared water level, it is equivalent to simultaneously extracting water from the interconnected power underground wells within a certain range. Extracting accumulated water causes the water level to be lower than the height of the cable duct to be maintained. However, due to the interconnectivity of the cable ducts, the accumulated water in the nearby power underground well will flow into the low water level section through the cable duct to achieve water level balance. Therefore, the cost of maintaining the power underground well without sealing cannot be estimated. Once emergency repairs occur, Running against time is even more challenging for emergency repair work.

       The traditional plugging cement, foam, fireproof mud and other plugging are only temporary emergency plugging, which can not prevent ponding and problems caused by ponding. Some hazardous cables even cause more trouble for cable maintenance. At present, inflatable cable duct sealing devices can effectively seal cable duct openings, but due to the functional limitations of their products, the required sealing effect is not ideal (see IDSS product comparison section for details)

       The following example is a field photo of Hangzhou Hengma Electric Power Technology Co., Ltd. sealing an underground well in Hefei. In the photo, the cable duct has been damaged, and the water level has risen to a low position at the cable duct outlet.

 

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