Valves are a kind of hardware products in common use. There are definite requirements for valves before or during assembling. Otherwise, valves having been assembled cannot show their excellent properties.
Requirements for valves before assembling:
1. According processing requirements, some components need to be polished. Burrs are not allowed to exist on the surface of components;
2. All of components should be degreased;
3. After degreasing, all of components should be passivated by using acid pickling. Cleaning agents cannot contain phosphorus;
4. All of components must be cleaned by using pure water, after being passivated through acid pickling. Insecticides cannot be maintained. If the components are made of carbon steel, the procedures skip.
5. Every component should be wiped by using non-woven fabrics. Cables cannot be kept on the surface. Components can be dried by using clean nitrogen.
6. Use non-woven fabrics or precise filter paper wet by pure alcohol to wipe components until no dirt colors.
Requirements for assembling technologies of valves:
1. Installation workshop should be kept clean, or temporary zone can be built. For example, use newly bought color-stripes clothes or plastic films to prevent dust from entering during assembling;
2. Works should wear clean purified cotton work clothes and cap. Hair cannot leak. Works also should put on clean shoes and plastic gloves which having been degreased;
3. Tools used for assembling should be degreased for cleaning before assembling to keep clean.
