The production line fully embodies the advanced technology, reliability, economy, as well as the rationality and wide applicability of the equipment. It can be adapted to the surface treatment of various kinds of workpieces with different materials or surface conditions of the workpieces to be treated. Under the conditions of standardized management, standardized operation and civilized production, in line with the principle of improving the labor environment and reducing the labor intensity of workers, the performance of the treated products will be more superior. The film quality of the coated products reaches the quality of similar products abroad, and the running cost of the coating is in line with the principle of economy.