Andrew J. Gellman Group S.O.P.
Venting a vacuum chamber
Precautions
- All electronic equipment must be turned off before venting the chamber. Failure to turn off equipment before venting could result in destruction of the instruments.
- All gate valves to pumps should be closed before venting to prevent pumps from operating outside the recommended pressure ranges.
- Leather gloves should be worn when loosening/tightening bolts to prevent minor cuts and abrasions.
Procedure
- Turn off all analytical equipment.
- Close all gate valves to pumps.
- Close valve to differentially-pumped rotary stages (if applicable).
- Unscrew 3 or 4 bolts on a small blanked flange until loose, creating a small air leak into the chamber.
- Allow leak to continue until hissing stops.
- Loosen a few more bolts, creating a larger leak of air into the chamber.
- Allow pressure to level off.
- Remove blank flange.
- Replace copper gasket.
- Rebolt blank to flange.
Note: Do not leave flange open to air for extended periods of time. Cover flange with foil if not immediately reattaching blank to flange.
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