Explanation of PPR tube quality error

PPR tube raw material is random copolymer polypropylene, which is what we call type ⅲ polypropylene. It is obtained by random copolymerization of propylene monomer and a small amount of ethylene monomer under heating, pressure and catalyst. Ethylene monomers are randomly distributed in the long propylene chain, and ethylene monomers are generally controlled between 3 and 5. The content of ethylene and the polymerization method of ethylene and propylene determine its cold brittleness.

In the case of low temperature, especially in the winter construction process, the flexibility of the pipe at low temperature is reduced, the rigidity is enhanced, and the performance is brittle. Under the impact of external force or excessive accidental load, linear cracking of pipe may occur. Bring inconvenience to the construction. Therefore, the relevant national norms have made clear requirements for this problem.

In winter construction, attention should be paid to the characteristics of low temperature brittleness of PPR pipeline for building water supply, and the corresponding construction plan should be formulated. GB/T50349-2005 has detailed provisions on this. When the ambient temperature is low, the toughness of PPR pipe is reduced, showing brittleness. When the pipe is impacted by external force or heavy pressure, linear cracking will occur, and the cracking situation starts from the inner pipe and extends to the outer pipe. When the pipe is cracked by the force of one point, the cracking will increase rapidly along the axis of the pipe in an instant. This characteristic is called rapid crack growth. In addition, the winter pipe in the transportation, in the site and installation process due to external force injury, will appear in the use of brittle and ductile pipe burst.

On the contrary, some fake PPR tubes with other raw materials are not easy to break. The PPR pipe that can deliver both hot and cold water can be used for 50 years can crack, especially in the case of low temperature, which is the low temperature brittleness of PPR.

If the PPR water pipe can not crack, it can be concluded that it is not PPR material. The advantages of PPR tubes are mainly reflected in the high creep resistance. The good pipe of pure PPR material has low temperature brittleness, which is particularly obvious in the environment below 5℃, so the good pipe can crack, and the crack is often not PPR pipe. This is not the same as some advertising, users should be careful when buying.