Process section flow of prepainted galvalume steel coil, the process section starts from the alkali degreasing treatment before the strip enters the alkali degreasing treatment of the process section, the rubber roller is lifted due to the instruction caused by punching, and the strip steel is brushed and sprayed. According to the speed of each group, the length of the alkaline washing tank is different, and some alkaline washing tanks are repeatedly set up. Then, rinse, squeeze dry, and pass into the surface treatment tank. For cold-rolled steel plates, phosphating treatment is carried out, and the surface-treated strip steel is washed and squeezed again and then enters the chroming treatment tank for spray treatment. After centering, it enters the roll coater for the coating of paint.
The primer on the front side is applied during the initial coating for the product strip which generally does not require double coating on both sides. When the strip joint is adjacent to the roller coaster, the punching in the middle of the strip triggers the instruction, and the roller coaster is in the cylinder. Drive back quickly, and after passing the strip joint, quickly reset to coat the strip, and the strip coated with the coating enters the baking and curing furnace. At this time, the strip and coating gradually heat up. During the heating process, the solvent in the coating film gradually volatilizes until the temperature reaches the minimum temperature required for the resin in the coating to carry out the cross-linking reaction and maintains it for a certain period. After leaving the hot air heating, the strip enters the air cooling section and begins to cool down while moving forward into the water cooling section. At this time, the strip is sprayed and sprayed to cool down. Finally, the strip begins to contact the support roller and is squeezed and dried. After one coating and baking, the strip steel returns to the second roller coater, and the coating rollers on the front and back sides simultaneously coat both sides of the strip steel and then continue to advance through baking, air Cooling, water cooling, drying, and entering the outlet looper through the tension roller.