Galvanized steel pipe is a steel pipe made by coating a layer of zinc on the surface of ordinary steel pipe (carbon steel pipe). Zinc has active chemical properties and can form a dense oxide film, thereby isolating oxygen and moisture and preventing the steel pipe from rusting.GI steel pipe is a metal pipe with zinc coating on the surface of ordinary steel pipe to prevent corrosion. It is divided into hot-dip galvanizing and electro-galvanizing. Hot-dip galvanized steel pipes are immersed in molten zinc liquid (about 450°C) to form a thicker zinc layer (50-150μm), which has strong corrosion resistance and is suitable for outdoor or humid environments; electro-galvanized steel pipe adopts electrolysis process, the zinc layer is thinner (5-30μm), the cost is lower, and it is mostly used indoors.