During the welding process of 3A21 aluminum plate, it is often found that the surface of the weld has pores, slag inclusion, incomplete penetration and other phenomena. The main reason is that the surface of the 3A21 aluminum plate is not clean after welding, leaving oil spots, alkali spots and large water marks , Macular, dark spots, etc. The pre-welding treatment of 3A21 aluminum plate is very important. In order to ensure the surface quality of 3A21 aluminum plate before welding, a strict cleaning plan should be adopted to completely remove the grease and oxide film on the pre-welding surface of 3A21 aluminum plate and welding joints. The quality of cleaning is directly related to the surface quality and welding quality of the 3A21 aluminum plate. 3A21 aluminum plate washing mainly includes degreasing and degreasing washing, chemical washing and mechanical washing. The washing scheme after the test is described now.

1. The cleaning workers in the cleaning workshop receive the ingredients from the auxiliary material warehouse according to the ingredient list, and add cleaning liquid to each cleaning pool.

2. Before cleaning, the dirt adhering to the surface of the 3A21 aluminum plate should be removed.

3. The surfaces of the 3A21 aluminum plates cannot overlap each other, and the 3A21 aluminum plates cannot be attached to each other, and leave a gap to ensure that the surface of the 3A21 aluminum plate is in full contact with the cleaning solution, and no scratches and collision deformation are allowed.