Galvanized steel pipe: it is used to make molten metal react with iron substrate to produce alloy layer, so as to combine the substrate and coating. First of all, the galvanized steel pipe is galvanized on the surface, and there is zinc coating on the outside. Without corrosion, it will not rust, but its hardness is not as high as that of seamless steel pipe, and it is widely used. Hot galvanizing refers to pickling the steel pipe first. In order to remove iron oxide on the steel pipe surface, after pickling, the steel pipe is cleaned in ammonium chloride or zinc chloride aqueous solution or mixed ammonium chloride and zinc chloride aqueous solution tank, and then sent to the hot dip tank. Hot dip galvanizing has the advantages of even coating, strong adhesion and long service life. The complex physical and chemical anti galvanized steel pipe shall be formed between the hot galvanized steel pipe substrate and the molten plating solution to form a corrosion resistant zinc iron alloy layer with compact structure. The alloy layer is integrated with the pure zinc layer and the steel pipe matrix. Therefore, it has strong corrosion resistance.
The high-quality seamless steel pipe is uniform in composition, looks neat on the cutting head, and feels smooth rather than pricked by burrs. Therefore, if the material is inferior, the cutting head will be uneven, and the whole steel pipe looks dull. If it is a fake seamless steel pipe, the color will be particularly obvious, showing a light red color, and the temperature of low-quality seamless steel pipe is not up to the standard.
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