Galvanized seamless tube is divided into cold-plated steel seamless pipe, hot dip seamless pipe.
Cold-plated seamless pipe
Cold galvanized is also electro-galvanized, galvanized the amount of small, only 10-50g/m2 of its own resistance to corrosion than hot dip galvanized pipe a lot of difference. Regular galvanized pipe manufacturers, in order to ensure the quality, most do not use electro-galvanized (cold-plated). Only those small-scale, outdated equipment and small businesses with electric galvanized, of course, their prices are relatively cheap. The Ministry of Construction has formally below, cold galvanized pipe to eliminate backward technology,it is not be allowed to cold galvanized pipe for water, gas pipes in the future.
Hot dip seamless pipe
Hot dip seamless pipe make the molten metal and iron substrate reaction to the alloy layer, so that the substrate and coating can be combined. Hot-dip galvanizing is the first steel pickling, in order to remove the steel pipe surface of iron oxide, pickling, aqueous solution of ammonium chloride or zinc chloride or ammonium chloride and zinc chloride mixed aqueous solution tank cleaning, and then send into the hot dip tank. Hot dip galvanized coating uniformity, strong adhesion, and long life.