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The process of automobile coating production line can generally be divided into two parts: first, the surface treatment of metal before coating, also known as pre-treatment technology; The second is the construction process of painting. Surface treatment mainly includes removing oil, dust, rust from the surface of the workpiece, as well as removing the old coating layer during repair operations, in order to improve the surface condition of the workpiece. This includes mechanical processing and chemical treatment of the workpiece surface according to various specific situations, such as phosphating, oxidation, and passivation treatment.

The process flow of the automotive coating production line is: pre degreasing → degreasing → hot water washing → cold water washing → acid washing → cold water washing → neutralization → cold water washing → surface adjustment → phosphating → cold water washing → hot water washing → pure water washing → drying