In recent years, the rapid development of PPR, but the quality of the products on the market are a mixture of fish beads uneven in quality, the phenomenon of. Whether the cold water pipe or hot water pipe, the material of the pipe should be the same, the cold and hot water pipes are only different in thickness. But currently on the market there is a common pipe and hot water pipe, water pipe and better material PPB (PPB block co polypropylene) posing as PPR, in this case, because of different materials, welding, welding, prone to fracture leakage dripping etc..
Consumers should pay attention to the identification marks on the tube, the product name should be "PP-R pipe" or "hot and cold water pipe with PP-R with hot and cold water, and express the implementation of national standards" GB/T18742-2002". Attention should be paid to when products are identified with other names or other standards.
Generally speaking, hot water pipe should be selected series of S for less than 2.5 of the pipe, that is, the outer diameter of 20 of the pipe wall thickness should be more than 3.4mm, 25 of the pipe wall thickness should be more than 4.2mm. In addition, the PPR pipeline brand price of linear expansion coefficient is about 10 times copper pipe, construction and installation should pay attention to the expansion and contraction left room.
Copper tubes: the chemical properties of copper are fairly stable and not susceptible to corrosion. The strength of the copper tube is much higher than that of the plastic tube, and it can withstand considerable pressure; and the steel tube has better toughness than that of the steel tube, and it doesn't crack or break under the strong frost heave and impact. Copper has a high melting point and a medium temperature of up to 200 DEG C, and it can work safely for a long time. Copper has good anti permeability, the use of the process, its surface can form a layer of protective film is not compact, medium dissolved, whether it is fat, carbohydrates, bacteria and viruses and harmful liquid oxygen or ultraviolet light, not through it and tube wall erosion.
The connection of copper pipe is mainly divided into two major categories: mechanical connection and brazing connection. Mechanical connections are divided into card sleeve type, plug-in type and crimp type connection.
The card sleeve type connection is a relatively simple construction method. It is easy to operate and easy to handle. It is a common connection method in construction. As long as the connection end of pipe cut to the pipe axis perpendicular to the incision, and burr clean, pipe assembly, the position of the circlip placed correctly, tighten the nut, tight connection can achieve copper.