The processing method of spraying a layer of plastic powder on the surface of the sprayed plastic bridge adopts corona discharge phenomenon to adsorb the powder on the cable bridge, which is more firm and beautiful. After melting at high temperature, the powder is solidified on the metal surface to form a coated layer, which can have different colors. The coating can effectively resist moisture and chemical corrosion. Different colors are easy to manage, and improve the beauty of the project; Some construction occasions have clearly proposed that the electrostatic spraying process must be used. Not suitable for outdoor exposure to ultraviolet light and easy to peel metal. Suitable for use in hot and humid environments such as basements.