In the continuous processing machine, cold rolled steel sheet and zinc galvanized steel sheet served as basal plate, one layer or several layers of liquid paint are painted onto the basal plate after surface pretreatment.

Steel sheet is changed into coated steel sheet after baking and cooling. As the layer bears different colors, thus coated
steel sheet is also known as color coated steel sheet. Besides, because painting is preceded prior to the formation processing,
coated steel sheet is also called as pre-coated steel sheet. .In this processing ,traditionally adopted spraying is replaced by
continuous painting, which is conducive to surface treatment,quality control of coating layer and avoid defects in edges.