Galvanized welded pipe is a type of steel pipe manufactured through a welding process. It uses steel strips or plates as raw materials and is welded into shape using methods such as furnace welding or electric welding to form a black pipe (i.e., ungalvanized steel pipe). Subsequently, a zinc layer is coated on the pipe wall surface through hot-dip galvanizing or electro-galvanizing (cold galvanizing) processes. Hot-dip galvanizing has become the mainstream application due to its thicker zinc layer and better corrosion resistance. Its main classification is based on the different galvanizing methods, divided into hot-dip galvanized welded pipe and cold-dip galvanized welded pipe (electro-galvanized welded pipe), with hot-dip galvanized welded pipe being widely used due to its superior performance.