Kinds of galvanized steel pipe

Galvanized steel pipe could devide into hot dipped galvanized steel pipeand cold galvanized steel pipe, the former has been disabled, the latter has been the state advocates can temporarily.

Hot dipped galvanized pipe is the molten metal and iron substrate reaction and produce alloy layer, so that the substrate and coating combination of both. Is hot dip galvanized steel pipes to pickling, in order to remove iron oxide on the surface of the steel tube after acid cleaning, by ammonium chloride or zinc chloride or ammonium chloride and zinc chloride mixed aqueous solution tank cleaning, and then sent to the hot dip plating tank. Hot dip galvanized with uniform coating, strong adhesion, long service life, etc. Steel substrate with molten electrolyte solution in complex physical and chemical reaction, the formation of corrosion resistance of the structure compact zinc alloy layer. Pure zinc alloy layer and layer and steel substrate. So the corrosion resistant ability.

Cold galvanized pipe

Cold galvanizing is electricity galvanized, galvanized quantity very few, only 10 to 50 g/m2, its corrosion resistance than galvanized pipe vary a lot. Normal galvanized pipe manufacturers, in order to guarantee the quality, most do not use electric galvanized (cold) plating. Only those small and old equipment of small businesses use electric galvanized, of course, their price is relatively cheaper. At present, the ministry of construction has officially below, eliminating backward technology of cold galvanized pipe, the future not be allowed to use cold galvanized pipe for water and gas pipe. The zinc layer is electrodeposited coating, zinc layer and steel substrate layered independently. The zinc layer is thinner, zinc layer attached on the steel substrate, simple easy to fall off. So the poor corrosion resistance. In the new residence, it is prohibited to use cold galvanization steel tube as a feed pipe.