wrought iron nails

Out-of-line annealing means that the recrystallization annealing of hot or cold rolled steel plate is carried out in the bottom type annealing furnace or cover type annealing furnace before entering the hot plating wire line, so that there is no annealing process in the galvanized line. The steel plate must maintain a clean active surface of pure iron, free of oxides and other dirt, before hot dip galvanizing. In this method, the annealed surface oxide sheet is first removed by pickling method, and then coated with a layer of zinc chloride or a mixture of ammonium chloride and zinc chloride solvent for protection, so as to prevent the plate from being oxidized again.

Because the coating obtained is thicker, hot-dip galvanizing has better protective performance than electric galvanizing, so it is an important protective coating for steel parts used in harsh working environment. Hot-dip galvanized products are widely used in chemical equipment, petroleum processing, Marine exploration, metal structure, electric power transmission, shipbuilding and other industries, in the agricultural field such as pesticide irrigation, greenhouse and construction industry such as water and gas transmission, wire casing, scaffolding, Bridges, highway guardrail and other aspects, has been widely used.