Galvanized square tube is divided into hot-dip galvanized square tube and cold-dip galvanized square tube from the production process. This square tube is based on a square tube formed by placing the square tube in a hot-dip galvanizing bath after a series of chemical reactions. The cold-galvanized square tube uses the principle of cold-galvanizing on the square tube used to make the square tube anti-corrosion.

Since the galvanized square tube is galvanized on the square tube, the application range of the galvanized square tube has been greatly expanded compared with the square tube. It is mainly used in curtain walls, construction, machinery manufacturing, steel construction projects, shipbuilding, solar power generation brackets, steel structure engineering, power engineering, power plants, agricultural and chemical machinery, glass curtain walls, automobile chassis, airports, etc.

There are two types of galvanized square tubes: hot-dip galvanized square tubes and electro-galvanized square tubes. There are wet method, dry method, lead-zinc method, redox method and so on for hot-dip galvanized square tube. The main difference between different hot-dip galvanizing methods is the method used to activate the surface of the pipe body to improve the quality of galvanizing after the steel pipe is pickled and cleaned. Dry method and oxidation-reduction method are mainly used in the current production, and their characteristics are shown in the table. The surface of the electro-galvanized zinc layer is very smooth and dense, with a uniform structure; it has good mechanical properties and corrosion resistance; the zinc consumption is 60% to 75% lower than that of hot-dip galvanizing. Electro-galvanizing is technically complicated, but it must be used for single-sided coating, double-sided coating with different thicknesses on the inner and outer surfaces, and thin-walled pipe galvanizing.