Mud and dust were found in the slot of No.2 water quenched cover plate on the surface of color coating unit. Dust was found on the inspection mirror at the outlet and floating dust was found on the surface of some rollers. Dust will affect the surface quality of color plate, especially the quality defect of aging paint explosion. The color coated roll has light weight, beautiful appearance, good corrosion resistance and can be processed directly.It is mainly used in advertising industry, construction industry, home appliance industry, electrical appliance industry, furniture industry and transportation industry. The steel plate not only has excellent anti rust performance, but also has good coating performance. Cold galvanizing, also known as electro galvanizing, is the use of electrolytic equipment to remove oil, acid and then put into the composition of zinc salt solution, and connected to the negative electrode of the electrolytic equipment.