Galvanized steel pipes are divided into cold-galvanized steel pipes and hot-dip galvanized steel pipes. Cold-galvanized steel pipes have been banned, and the latter is also recommended by the state to be temporarily used. In the 1960s and 1970s, developed countries in the world began to develop new

Galvanized steel is widely used in all walks of life. The advantage of using galvanized steel is to use metallic zinc that can form a dense oxide protective layer in the air to protect the internal steel structure. In the case of welding or scratching, due to the existence of the Zn-Fe galvanic