1. The coating film is too thin

Increase the coating thickness of the coating film

2. Unclean spraying environment

The spraying room should be clean, the air should be purified, and the workshop should be kept clean.

3. Unclean baking environment

(A) control the amount of air blowing in the baking oven, regular cleaning of the oven
B）The inner wall of the oven should be made of high-temperature resistant material that is not easy to rust, preferably stainless steel

4. There are impurities falling from the hangers, such as rust, glue particles, etc.

Regular cleaning of hangers

5. Pre-treatment is not good (such as poor surface adjustment, so that the phosphate film is rough, and in severe cases, the formation of dust, resulting in fine particles in the coating film)

Enhanced pre-treatment control

6. The powder itself has a small number of impurities

Detection of the solvent sieve residue of the powder, check whether the standard is exceeded