At present, the main water supply pipe for residential decoration is PPR pipe and copper pipe.
PPR tube: The formal name for PPR is random copolymer polypropylene, which is a random copolymer of propylene and other olefin monomers. There is no other functional group in the olefin monomer.
As a new type of pipe, PPR pipe has the following characteristics:
1. Health, non-toxic, can be used directly for pure water, drinking water pipe system.
2. Corrosion resistance, not easy to scale, eliminating galvanized steel rust scaling caused by secondary pollution.
3 heat, long-term transport temperature below 70 ℃ hot water, can withstand the instantaneous high temperature of 95 ℃.
4. Insulation performance is good, the thermal conductivity at 20 ℃ is only about 1/200 of the steel pipe, 1/1400 of the copper pipe.
5. Light weight, high strength, PPR density of 0.89 ~ 0.91g / cm3, only 1/9 of the steel pipe, 1/10 of the copper pipe.
6. Pipeline fluid resistance is small, pipe wall smooth, easy scaling, fluid resistance is much lower than the metal pipe.
7. Using hot melt socket connection, the installation is simple and reliable, long service life.
In recent years, the rapid development of domestic PPR pipe, but the product quality in the market varies greatly, there are numerous. Whether cold or hot water pipes, pipe material should be the same, cold, hot water pipe wall thickness is different. However, at present, pipes and hot water pipes are more commonly used in the market, and PPR (PPB is block copolymerized propylene) is used as the cold water pipe. In this case, the welding place is prone to fracture due to different materials , Desoldering, leaks and so on.
Consumers should pay attention to identify the logo on the pipe, the product name should be "hot and cold water with a random copolymer polypropylene pipe" or "hot and cold water PP-R pipe", and expressly implemented the national standard "GB / T18742-2002 ". When the product is found to be given a different name or other standards should pay attention.
In general, the hot water pipe should use pipe series S is 2.5 below the pipe, which is the outer diameter of 20 pipe wall thickness should be 3.4mm above, 25 pipe wall thickness should be 4.2mm above. In addition, linear expansion coefficient of PP-R pipe is about 10 times that of copper pipe, should pay attention to leaving room for expansion and contraction during construction and installation.