History of water supply pipeline evolution history of water supply pipeline
The selection and installation of water pipes in concealed works has become a problem that cannot be ignored in the decoration. In order to make the living room beautiful, people use wall-embedded construction in the decoration water pipes. Once the water pipes leak and burst, it will be difficult to make up. as a result of.
In the past, the pipes used for water supply were mainly cast iron pipes. The outdoor mainly uses sand mold cast iron pipes, and the indoor uses galvanized cast iron pipes, which can be divided into cold (electric) galvanizing and hot galvanizing. The galvanized pipe is used as a water pipe. After a few years of use, a large amount of rust is generated in the pipe. The yellow water that flows out not only pollutes the sanitary ware, but also is mixed with bacteria that grow on the inner wall of the slick. The rust causes the heavy metal content in the water to be too high, which seriously endangers the health of the human body.
The state has stipulated that on June 1, 2000, sand mold cast pipe fittings and cold galvanized cast iron pipes will be eliminated, the use of hot-dip cast iron pipes will be gradually restricted, and aluminum-plastic composite pipes and new plastic pipes will be promoted. Therefore, there are three main types of pipelines currently in use. The first type is a metal tube, such as a hot-dip cast iron tube, a copper tube, a stainless steel tube, etc. of the inner plastic. The second category is plastic-plastic pipes, such as plastic-coated steel pipes and aluminum-plastic composite pipes. The third category is plastic pipes, such as PP-R (cross-linked poly{TodayHot} propylene high-density mesh engineering plastics).
The state also stipulates that all kinds of pipes and fittings involving drinking water pipelines must be approved by the health department before they can be sold. 
Editor in charge: Wang Zhen
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