Galvanized coil, the thin steel plate immersed in the molten zinc bath, so that its surface adheres to a layer of zinc thin steel plate. At present, continuous galvanizing process is mainly used to produce galvanized steel sheet, which is made by continuously immersing coiled steel sheet in galvanized bath and alloying galvanized steel sheet. This kind of steel plate is also made by hot dipping method, but it is heated to about 500 C immediately after the trough is out to form zinc and iron alloy film. The galvanized coil has good adhesion and weldability of the coating.