The color-coated steel plate is pickled after welding. If the treatment is not good, it will easily cause the color-coated steel plate to be corroded. Therefore, we should pay attention to the following points during the pickling process:
1. Sulfuric acid can also be used for pickling, and the pickling time should not be too long.
2. Oxalic acid for surface adjustment, use concentration 1~2.
3. Weak alkaline degreasing must be used for degreasing, and it must not contain flake alkali. The TAL must be controlled at about 15 POINT and the PH must not exceed 13.
4. The acidity of zinc phosphating treatment should take the upper limit, and the concentration of dipping treatment: TA: 35 or more; FA: 1.2AC: 8 (20CC fermentation tube).
5. Neutralize with 1-2 sodium carbonate after pickling.
6. It is not necessary to clean the color-coated steel plate and keep it overflowing.
