Valve components must go through the following procedures before assembly:

source：https://baike.baidu.com/item/閥門     adding：2019/9/16 15:07:00

1. According to the processing requirements, some parts need to be polished, and the surface should not have processing burrs, etc.;

2. Degreasing all parts and components;

3, after the degreasing is completed, the pickling passivation, cleaning agent does not contain phosphorus;

4, after pickling and purification, rinse with pure water, no pharmaceutical residue, carbon steel parts omitted this step;

5. Each part shall be wiped dry with non-woven cloth, and the surface of the parts shall not be retained with wired wool, or blown dry with clean nitrogen;

6. Use non-woven cloth or precision filter paper to dip analysis of pure alcohol to wipe each part until there is no dirty color.