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What are the working principles of drill pliers?

PE pipe opening and plugging technology is an operating method for non-stop construction of pipeline networks and pipelines in operation, which is mainly completed by special opening equipment for polyethylene pipes. Its basic principle is: double-sealing and double-blocking at both ends of a pipeline section that needs to be subjected to various construction or repair operations on a pipeline running under pressure. Use open-hole blocking equipment to cut off the medium flow of the pipeline section and use erection. Temporary bypass connections on the opening blocking equipment at both ends of the pipe section are connected to both ends of the pipeline during the construction operation, allowing the medium in the pipeline to continue to be transported continuously through the temporary bypass, so that the entire pipeline will continue to be transported normally during the construction operation run. According to the purpose of the construction operation and the use of different pipeline structure forms, double sealing and double blocking must be carried out when replacing valves, replacing pipe sections or pipelines on pipelines under pressure, inserting tee joints on pipelines, and handling other pipeline failures. Forms of openings. At this time, the purpose of the hole opening is to block, that is, two hole opening machines of the same specification and type are installed at both ends of the construction pipe section, and are connected to the special polyethylene pipe fittings which are fused to the pipeline in advance, and the hole opening knife extends into the PE. A hole is formed in each of the mother pipes of the pipe, and the size of the hole is determined by the specifications of the plugging head used. After the opening is completed, the occluder performs the plugging. The occluder lowers the occluder into the opened hole, and operates the occluder to open the folding leather bowl or “sandwich” butterfly valve. The occluder cuts the medium back to back in the inner hole at both ends of the pipe section.