1. Hot galvanized sheet: dip the sheet into the molten zinc tank to make the surface adhere to a zinc sheet. It is mainly produced by continuous galvanizing process, that is, the rolled steel sheet is continuously immersed in the molten zinc plating bath to make galvanized steel sheet. Alloy galvanized steel sheet. This kind of steel plate is made by hot dip method, but after the slot, immediately heated to a temperature of about 500 ℃, it make the generation of zinc and iron alloy membrane. The galvanized sheet has good coating tightness and weldability.2. According to different annealing methods, hot-dip galvanizing can be divided into two types: line internal annealing and line external annealing, which are also called protective gas method and flux method respectively.