Large steel structure buildings and steel structure bridges will scientifically develop metal anti-corrosion expectations based on the differences in atmospheric and chemical corrosion environments they are in. High performance epoxy zinc rich primer, cloud iron intermediate paint or various thick paddle epoxy paints provide long-lasting electrochemical protection or barrier function, combined with weather resistant polyurethane, polysiloxane, fluorocarbon topcoats, jointly endowing steel structures with long-term protection function. The various amine curing agents provided by Meidong Biotechnology can be matched with different customers' epoxy main paints to achieve good mechanical and anti-corrosion properties of epoxy coatings, providing application solutions for C4 and above corrosive environments.