Color coating unit process The main processes of the co […]
Color coating unit process
The main processes of the corrugated steel sheet unit include pretreatment process, coating process, baking process and post-treatment process. Most of the color coating units are two-coating and two-bake production processes, and also have three-coating and three-baking processes.Simple process includes: unwinding, stitching, inlet looper, cleaning, chemical treatment, initial coating, initial coating baking, initial coating cooling, fine coating, fine coating baking, fine coating cooling, export looper, inspection, printing , cut, take.
After the coil is unwound, it is degreased, washed with water, and then phosphatized or composite oxidized to form a phosphate or composite oxide film on the surface of the steel sheet, and then passivated and sealed to form a pretreatment film to improve the relationship between the substrate and the coating. An effective means of combining forces.
The color coating unit generally applies a coating to the surface of the strip by means of roll coating. Roll coating is a coating method in which a certain thickness of wet film is formed on a roll and then transferred to the surface of the strip.
The curing of the coating refers to the process of chemical polycondensation, polyaddition, cross-linking, etc., from a liquid state to a solid state through a main film-forming substance and an auxiliary film-forming substance and a curing agent under a certain temperature and other conditions. For high-speed units, the coating solvent is required to evaporate quickly, the curing temperature is high, the curing speed is fast, and the time is short.