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Rigid waterproof casing is a steel pipe plus wing ring (steel ring made on the ring tube), installed in the wall (mostly concrete wall), for the general pipe through the wall, which is conducive to waterproof walls, flexible waterproof casing in addition to the external Wing ring, the internal file ring and the like, the flange wire, there are sets to sell, but also their own processing, for the need for shock control pipeline, such as water pipes and pipes connected to the wall. In other words, if you consider the waterproof performance on both sides of the wall, it is necessary to use flexible waterproof casing; if only to consider the pipe through the wall, without considering the wall, the wall on both sides of the waterproof performance and displacement of the pipeline deformation You can use rigid waterproof casing. Then the general packing pipe is simple, and generally packing casing for pipe wall and floor protection, mainly for the subsequent replacement and maintenance of the pipeline. When the general casing is used to pass through the foundation, the inner wall, the floor, etc., to avoid the pipeline (such as water supply, such as water supply, heating, etc.), the building is disturbed and easy to install and maintain the pipeline, Greater than the installation of pipe diameter, material and length are in line with the requirements, installed in the foundation, interior walls, floors and other pipes through the short tube.