Drainage pipeline refers to the collection system of sewage, wastewater and rainwater drainage pipelines and ancillary facilities. Including dry pipes, manifolds and pipes leading to treatment plants, or anywhere else, whether built on streets, as long as they serve as drainage pipes, drainage channels should be used as statistical data. All sewers, branch pipes and inspection wells have drainage lengths, connection lengths and computed entrances and exits, excluding connection pipes from rainwater outlets to pipes and open channels to enter homes. When calculating a single pipe, it should be calculated that the drainage passage should be calculated according to the length of each calculation in two or more places drained side by side on the same street.


Piping type
Galvanized iron pipe is one of the most widely used materials at present. Because galvanized iron pipe corrosion causes high content of heavy metals in water and affects human health, government departments in many countries and regions have begun to explicitly prohibit the use of galvanized iron pipe. At present, China is phasing out this type of pipeline.


Brass is a more traditional but expensive pipe material, durable, more convenient to construct. In many imported sanitary products, brass is the first choice. Price is the most important factor affecting its use, on the other hand, copper corrosion.


Stainless steel pipe is a more durable pipe material. But its price is high, and the construction process is relatively high, especially the strength of materials is very difficult, and the on-site processing is very difficult. Therefore, the probability of renovation project is low.


Plastic composite pipe is a kind of popular pipe material, which is light in weight, durable, easy to construct, and more suitable for bending household use. Its main disadvantage is the use of hot water pipes, because thermal expansion and contraction will cause long-term displacement of the wall leading to leakage