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中文简体1. Compared with metal pipes, PP-R pipes have lower hardness and poorer rigidity. They should be protected during transportation and construction to avoid mechanical damage caused by inappropriate external forces. After concealed application, the position of the pipeline should be marked to avoid secondary decoration from damaging the pipeline.
2. PP-R pipes have certain low-temperature brittleness below 5°C. Be careful in winter construction, and use sharp knives to cut slowly when cutting pipes. The installed pipes cannot be heavily pressed or knocked, and if necessary, the parts that are vulnerable to external forces should be covered with protective materials.
3. PP-R tubes are prone to aging and degradation due to long-term exposure to ultraviolet rays. When installed outdoors or in direct sunlight, they must be wrapped with a dark protective layer.
4. Except for the mechanical connection methods such as threaded inserts or flanges used to connect PP-R pipes with metal pipes or water containers, the rest should be connected by hot melt to make the pipes integrated without leakage points.
5. The linear expansion coefficient of PP-R pipe is relatively large (0.15mm/m°C), and technical measures must be taken to prevent pipe expansion and deformation when laying pipes for surface installation or non-direct burial.
6. After the pipeline is installed, the pressure must be tested before sealing the pipeline (direct burial) and covering the decorative layer (non-direct burial). The pressure test pressure of the cold water pipe is 1.5 times the working pressure of the system, but not less than 1MPa; the test pressure of the hot water pipe is 2 times the working pressure, but not less than 1.5MPa. The pressure test time and method are stipulated in the technical regulations.
7. When laying PP-R pipes in the open or non-direct buried concealed laying, the supports and hangers must be installed according to the regulations.
8. Cool down to the specified time and complete the connection.
