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Classification of Galvanized Pipe

Feb. 20, 2020

I. Overview of Galvanized Pipe

In order to improve the corrosion resistance of steel pipes, general steel pipes are galvanized. Galvanized pipe (galvanized steel pipe) is divided into two types: hot-dip galvanized and cold-galvanized. The hot-dip galvanized layer is thick, has the advantages of uniform coating, strong adhesion, and long service life. Cold galvanized pipe has low cost and the surface is not very smooth. Its corrosion resistance is much worse than hot galvanized pipe, and it has been gradually phased out.

Hot dipped galvanized tube is an alloy layer produced by reacting molten metal with an iron substrate, thereby combining the substrate and the plating layer. Hot-dip galvanizing is to pickle the steel pipe first. In order to remove iron oxide on the surface of the steel pipe, after pickling, it is washed in an ammonium chloride or zinc chloride aqueous solution or a mixed aqueous solution of ammonium chloride and zinc chloride and then sent Hot dip plating bath. Hot-dip galvanizing has the advantages of uniform coating, strong adhesion and long service life. The hot-dip galvanized steel pipe substrate and the molten plating solution undergo complex physical and chemical reactions to form a corrosion-resistant and dense zinc-iron alloy layer. The alloy layer is integrated with the pure zinc layer and the steel pipe base, so its corrosion resistance is strong.

Classification and characteristics of galvanized pipe

Galvanized pipes are divided into hot-dip galvanized steel pipes and cold-galvanized steel pipes, of which cold-galvanized steel pipes have been gradually phased out.


Hot Dipped Galvanized Tube

Hot Dipped Galvanized Tube

1.Hot galvanized steel pipe

Hot-dip galvanizing is the reaction of molten metal with an iron substrate to produce an alloy layer, thereby combining the substrate and the plating layer. In the manufacture of hot-dip galvanized steel pipe, the steel pipe is first pickled to remove iron oxide on the surface of the steel pipe. After pickling, it is cleaned in an ammonium chloride or zinc chloride aqueous solution or a mixed aqueous solution of ammonium chloride and zinc chloride. , And then sent to the hot-dip plating bath.

Hot dipped galvanized steel pipe is a complex physical and chemical reaction between the steel pipe substrate and the molten plating solution, forming a corrosion-resistant and dense zinc-iron alloy layer. The alloy layer is integrated with the pure zinc layer and the steel pipe base, so the hot-dip galvanized steel pipe has the advantages of uniform coating, strong adhesion and long service life.