The hot-dip galvanized pipe is to make the molten metal and the iron matrix react to produce an alloy layer, so that the matrix and the coating are combined. Hot-dip galvanizing is to first pickle the steel pipe. In order to remove the iron oxide on the surface of the steel pipe, after the pickling, it is cleaned in a tank of ammonium chloride or zinc chloride aqueous solution or a mixed aqueous solution of ammonium chloride and zinc chloride, and then sent to In the hot dip plating tank. Hot-dip galvanizing has the advantages of uniform coating, strong adhesion and long service life. The matrix of the hot-dip galvanized steel pipe undergoes a complex physical and chemical reaction with the molten plating solution to form a corrosion-resistant zinc-iron alloy layer with a compact structure. The alloy layer is integrated with the pure zinc layer and the steel pipe matrix, so it has strong corrosion resistance.
