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Valve cleaning steps and assembly requirements

Valve cleaning steps:

The valve parts must go through the following processes before assembly:

ductile iron, DI, butterfly valve, manufacturer, center line, TH valve

ductile iron, DI, butterfly valve, manufacturer, center line, TH valve

  • According to the processing requirements, some parts need to be polished, and the surface must not have processing burrs, etc.;
  • All parts are degreased;
  • After degreasing is completed, pickling passivation is carried out, and the cleaning agent does not contain phosphorus;
  • Rinse with pure water after pickling and purification, and there should be no residues of medicament, and this step is omitted for carbon steel parts;
  • Dry the parts one by one with a non-woven cloth, and do not leave the surface of the parts such as wire wool or dry with clean nitrogen;
  • Use non-woven fabric or precision filter paper dipped in analytical pure alcohol to wipe each part until there is no dirty color.

Valve assembly requirements:

The cleaned parts must be sealed and stored for installation. The requirements for the installation process are as follows:

  •  The installation workshop must be clean, or set up a temporary clean area, such as newly purchased color striped cloth or plastic film, to prevent dust from entering during the installation process.
  • Assemblers must wear clean cotton overalls, cotton caps, no leakage of hair, clean shoes on feet, and plastic gloves on hands.
  • Assembly tools must be degreased and cleaned before assembly to ensure cleanliness.

other requirements:

1. Purge the assembled valve with nitrogen for at least 1 minute.
2. The air tightness test must use pure nitrogen.
3. After passing the air tightness test, encapsulate and seal with a clean polyethylene cap. The polyethylene cap should be soaked in organic solvent and wiped clean before use.
4. Then seal it with a vacuum bag.
5. Final packing.
6. Measures must be taken to ensure that the package is not damaged during transportation.
4. Acceptance requirements
The acceptance is followed. Before assembly, each component is wiped with clean precision filter paper. If the dead corner of the component is selected, the filter paper does not change color as qualified.

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