Rust of Galvanized Steel Pipe

Galvanized steel pipe is the use of cold-rolled or hot rolled steel plate technology will be narrow and long plate coated with a layer of zinc, pided into hot-dip galvanized and electro-galvanized, hot dip galvanized coating more uniform, strong adhesion and long service life. The chemical reaction with the bath can make galvanized steel pipe corrosion resistance, even if there is a strong corrosion resistance, rust or the phenomenon of the process will occur, then, what is the reason for this?

Rust of galvanized steel pipe is the main reason that the surface layer of zinc plated. Zinc is relatively active in chemistry, soluble in both acids and alkalis, and chemically reacts with zinc in humid environments to form a basic zinc carbonate membrane on the surface. In contact with substances containing hydrogen sulfide, the zinc resistance Corrosion decreased, easily corroded, exposing the steel surface, the final rust. Galvanized with a lower probability of rust, because the coating is relatively thick galvanized steel, not easy to cause the oxidation of steel, it is not easy to rust.