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What is Galvanized Pipe?

Nov. 25, 2020

Galvanized pipes are galvanized pipes made of steel strips or coils that are spirally bent and formed by double-sided submerged arc automatic welding for internal and external seams. It can be widely used in construction and machinery due to the following reasons , Coal mines, chemicals, railway vehicles, automobile industry, highways, bridges, containers, sports facilities, agricultural machinery, petroleum machinery, prospecting machinery and other manufacturing industries.

Classification of galvanized pipe

The classification of galvanized pipe: galvanized steel pipe is divided into cold-plated pipe and hot-dipped pipe.

1. Hot-dip galvanized pipe

Hot-dip galvanized pipe is to make the molten metal react with the iron matrix to produce an alloy layer, so that the matrix and the coating are combined. Hot-dip galvanizing is to pickle the steel pipe first, in order to remove the iron oxide on the surface of the steel pipe, after pickling, It is cleaned by ammonium chloride or zinc chloride aqueous solution or ammonium chloride and zinc chloride mixed aqueous solution tank, and then sent to the hot-dip plating tank. Hot-dip galvanizing has the advantages of uniform coating, strong adhesion and long service life.

2. Cold galvanized pipe

Cold galvanizing is electro-galvanizing, and the amount of galvanization is very small, only 10-50g/m2, and its corrosion resistance is much different than that of hot-dip galvanized pipe. Formal galvanized pipe manufacturers, in order to ensure quality, most of them do not use electroplating Zinc (cold galvanizing). Only those small enterprises with small scale and outdated equipment use electro-galvanizing, and of course their prices are relatively cheaper. At present, the Ministry of Construction has officially eliminated the cold galvanized pipes with backward technology. Galvanized pipes are used as water and gas pipes.

Galvanized Pipe

Advantages of hot-dip galvanized pipe

1. Hot-dip galvanizing has the advantages of uniform coating, strong adhesion and long service life. The galvanized tube matrix 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. Therefore, its corrosion resistance is strong.

2. As long as the forming angle is changed, steel pipes of various diameters can be produced from strip steel of the same width, which is easy to adjust. Because it is continuously bent and formed, the length of the spiral tube is not limited, and the length can be set at will.

3. The spiral shape of the weld is evenly distributed on the circumference of the spiral tube, so the spiral tube has high dimensional accuracy and strong strength.

4. Easy to change the size, suitable for the production of small batches and multiple varieties of spiral pipes. The weld seam of the galvanized pipe is longer than the weld seam of the straight seam pipe of the same specification. With the same wall thickness, the hot-dip galvanized steel pipe bears greater pressure.

5. Welded steel pipe with hot-dip galvanized or electro-galvanized layer on the surface of galvanized pipe. Galvanizing can increase the corrosion resistance of the steel pipe and prolong the service life.

The above information is provided by galvanized pipe factory.

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