Hot galvanized steel pipe go through series production procedure of hot-dip galvanized, zinc-rich coated epoxy, torrefied under 500℃ in the heating box , polyester color coated. Torrefied under 500℃ in the same heating box, the two torrefy procedure is aim at anti-ultraviolet radiation, anti-rust, anti-corrosion and keep clean by itself because of lubricity appearance character.fences also possess characteristics of anti corrosion.antirust,and resist ultraviolet radiation.these advantages keep avoid from maintenance cost.according to a data from the relative research,the maintenance cost by using other plastic fences or cast iron fences is 3.8-3.9 USD each year/time.