The Difference between Hot-dip Galvanized Pipes and Normal Galvanized Pipes

1. Different production

Galvanized steel pipe is divided into cold galvanized steel pipe and hot galvanized steel pipe. Cold galvanized steel pipe has been banned. In the 1960s and 1970s, developed countries began to develop new types of pipes and banned galvanized pipes.

Hot-dip galvanized pipes are used to galvanize common steel pipes in order to improve the corrosion resistance of steel pipes. There are two types of galvanized steel pipes: hot-dip galvanized and electro-galvanized. The hot-dip galvanized galvanized layer is thick, the cost of electro-galvanized is low, and the surface is not very smooth.

2. The working principle is different

The hot-dip galvanized tube reacts the molten metal with the iron substrate to produce an alloy layer, thereby combining the substrate and the plating layer. 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, wash through the ammonium chloride or zinc chloride aqueous solution or ammonium chloride and zinc chloride mixed aqueous solution tank and then send Hot dip plating bath.

The surface of the galvanized steel pipe is a hot-dipped or electro-galvanized welded steel pipe. Galvanizing can increase the corrosion resistance of steel pipes and prolong their service life. Galvanized pipes are widely used. In addition to being used as pipeline pipes for general low-pressure fluids such as water, gas, oil, etc., they are also used as oil well pipes and oil pipelines in the petroleum industry, especially in offshore oil fields, oil heaters and condensation in chemical coking equipment. Tubes for coolers, coal distillation oil washing exchangers, trestle tube piles, support pipes for mine tunnels, etc.

3. Different characteristics

Hot dip galvanizing has the advantages of uniform coating, strong adhesion and long service life. The complex physical and chemical reactions between the steel pipe substrate and the molten plating solution form a tightly structured zinc-iron alloy layer with corrosion resistance. The alloy layer is integrated with the pure zinc layer and the steel pipe substrate. Therefore, its corrosion resistance is strong.

Hot dip galvanized steel pipes are widely used in manufacturing industries such as construction, machinery, coal mines, chemical industry, electric power, railway vehicles, automobile industry, highways, bridges, containers, sports facilities, agricultural machinery, petroleum machinery, and prospecting machinery.