Procedure requirements and inspection of the hotte

Step requirements and inspection of degreasing valve

1. Cleaning steps:

the parts and components of the valve must be treated in the following process before assembly:

1) according to the processing requirements, some parts and components need to be polished, and the surface must be free of machining burrs

2) degrease all parts

3) after degreasing, acid pickling and passivation (the cleaning agent does not contain phosphorus)

4) after pickling and passivation, rinse it with pure water, and there shall be no reagent residue (this step is omitted for carbon steel parts)

5) wipe the parts one by one with non-woven cloth, and do not leave the surface of parts such as wire wool. To understand the knowledge about the experimental machine, we Jinan new era Gold Testing Instrument Co., Ltd. are the most professional or blow dry with clean nitrogen

6) wipe each part with non-woven fabric or precision filter paper dipped in analytical pure alcohol until there is no dirty color

2. Assembly requirements

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

1) the installation workshop must be clean, or a temporary clean area (such as a newly purchased colored strip cloth or plastic film) must be built to prevent dust from entering during the installation process

2) if it is installed in other directions, the Leeb hardness value is obviously untrue. The matching workers must wear clean cotton overalls, wear pure cotton hats, do not leak their hair, wear clean shoes on their feet, and wear plastic gloves (degreasing)

3) tools for assembly must be degreased and cleaned before assembly to ensure cleanliness

3. Other requirements

1) purge the assembled valve with nitrogen for at least 1 minute

2) the air tightness test must be carried out with pure nitrogen

3) after passing the air tightness test, seal it with a clean polyethylene cap. The polyethylene cap should be soaked in organic solvent and wiped clean before use

4) then seal with vacuum bag

5) final packing

6) measures shall be taken during transportation to ensure that the package is not damaged

4. Acceptance requirements

while paying attention to research and development,

acceptance shall comply with Hg specification for construction and acceptance of degreasing engineering. Before assembly, each part shall be wiped with clean precision filter paper (select the dead corner of the part), and the filter paper is qualified if its color remains unchanged