This judgment method is wrong, whether to crack the PPR tube, this is a mistake to judge whether PPR is good or bad, which can not test whether PPR is good or bad, because the performance of PP-R material itself changes with the ambient temperature to a certain extent. In the case of low temperature, especially in winter, the flexibility of the pipe is reduced at low temperature, the rigidity is increased, and the performance is brittle.
Some fake PPR pipes with other raw materials are not easy to break. The real PP-R that can transport both high temperature hot water and cold water can be used for 50 years can be cracked, and the good pipe of pure PP-R material has low temperature brittleness, which is particularly obvious in the environment below 5 ° C, which is the low temperature brittleness of PP-R. If the PP-R water pipe can not be cracked, it can be concluded that it is not a real PP-R material.
How to effectively avoid the low temperature brittleness of the pipe in the actual transportation or construction process?
Transportation and storage
PPR pipe is strictly forbidden to throw, drop, roll or drag during handling; The pipe shall be stored in the warehouse, and the stacking height shall not exceed 1.5m.
Construction precautions
Winter construction should be careful, the pipe should be cut slowly with a sharp tool. The installed pipeline should not be pressed or knocked, and the vulnerable parts should be covered with protective material if necessary.
Before cutting the pipe, if the pipe is found to be white due to external factors, the pipe cannot be used. Before the hot melt connection, carefully check whether the pipe has been damaged. Especially the inner wall, because when the pipe is subjected to external force, the inner wall breaks first and then goes outside. Avoid using the pipe whose inner wall has been broken but the outer pipe has not been broken.
Post-installation test
After installation, pressure test must be carried out before direct and indirect burying. The pressure test pressure of the cold water pipe shall be 1.5 times the working pressure of the system, but shall not be less than 0.9MPa; The test pressure of the hot water pipe is 2 times the working pressure, and the pressure test must be carried out before the direct burial and non-direct burial after the installation of the pipe. The pressure test pressure of the cold water pipe shall be 1.5 times the working pressure of the system, but shall not be less than 0.9MPa; The test pressure of the hot water pipe is 2 times the working pressure, but not less than 1.2MPa. But not less than 1.2MPa..