Galvanized steel pipe produce: Hot dip galvanized steel pipe with pickling, first to remove iron oxide on the surface of the steel tube, after acid cleaning, by ammonium chloride or zinc chloride or ammonium chloride and zinc chloride mixed aqueous solution tank cleaning, and then sent to the hot dip plating tank. Hot dipped galvanized zinc layer thickness, coating uniformity, strong adhesion, long service life, etc. Steel substrate with molten electrolyte solution in complex physical and chemical reaction, the formation of corrosion resistance of the structure compact zinc alloy layer. Pure zinc layer, alloy layer and steel substrate fused together . So the corrosion resistant ability.