Principle of hot-dip galvanized steel pipe and application of hot-dip galvanized steel pipe in production. In order to improve the corrosion resistance of hot-dip galvanized steel pipes, hot-dip galvanizing is carried out on ordinary steel pipes. The hot-dip galvanized steel pipe is divided into hot-dip galvanizing and phosphating treatment. The hot-dip galvanized layer is thick, the phosphating cost is low, and the surface is not smooth and clean. At present, hot-dip galvanized steel pipes and hot-dip galvanized pipes are the most widely used.
Hot dip galvanizing, also known as hot dip galvanizing and hot dip galvanizing, is a reasonable method for metal corrosion, which is mainly applied to metal components and equipment in various fields. After antirust treatment, the alloy infiltrates into the molten zinc at 500 ℃, which makes the surface of the steel prefabricated components adhere to the zinc layer, thus achieving the purpose of anti-corrosion. Hot galvanizing production process: pickling and passivation - water cleaning - adding plating aid - air drying - hanging plating - cooling - chemical - cleaning - grinding - polishing - hot galvanizing is completed. What is the working principle of hot-dip galvanized steel pipe?
Principle: Hot galvanizing refers to the formation of zinc in high-temperature liquid by the following three processes:
First, the zinc liquid on the iron base surface melts to form a zinc nonferrous metal phase layer;
The zinc ions in the aluminum alloy layer further diffuse to the matrix, forming a zinc iron phase soluble layer;
A linear zinc layer on the surface of the aluminum alloy layer.
The hot-dip galvanized steel pipe has a thick high-density pure zinc coating on the steel surface, which can prevent the steel substrate from contacting with the aqueous solution, thus protecting the steel substrate from corrosion. In ordinary air, an extremely thin and dense active zinc oxide layer is generated on the surface of the zinc layer, which is difficult to dissolve water on the surface, so it plays a certain role in maintaining the steel substrate. If the active zinc oxide and other components in the air are converted into insoluble zinc salts, the corrosion resistance will be more ideal.
Hot dip galvanized pipe is a layer of aluminum alloy formed by the reaction of molten metal materials and iron matrix, so that the matrix and coating are closely combined. Hot galvanizing refers to pickling and passivation of steel pipes. In order to better remove the compound on the steel pipe surface, after pickling and passivation, the steel pipes shall be cleaned by ammonium chloride, magnesium chloride solution or mixed solution tank of ammonium chloride and magnesium chloride, and then sent to the hot dip plating tank. Hot dip galvanizing has the advantages of uniform coating, strong adhesion and long service life. The complex physical and organic chemical anti hot-dip galvanized steel pipes are produced by the hot-dip galvanized steel pipe matrix and molten plating solution, forming a zinc nonferrous metal layer with compact structure and corrosion resistance. Aluminum layer is combined with pure zinc layer and steel pipe substrate. Therefore, the corrosion resistance is very strong.
