Galvanization or galvanizing is the process of applying a protective zinc coating to steel or iron, to prevent rusting. The most common method is hot-dip galvanizing, in which the parts are submerged in a bath of molten zinc.
Galvanized pipe can be divided into cold galvanization and hot-dipped galvanization. Hot -dipped galvanization has many advantages, such as thick galvanizing layer, uniform galvanizing layer, strong adhesion and long useful life,etc. While for cold galvanization (also called electroplated zinc), its cost is lower, surface is not smooth, corrosion resistance is much worse than hot-dip galvanized pipes. At present in China, cold galvanization has been banned, hot-dipped galvanization can be used temporarily.