Titulo del Topic

Description of the operation for NEXT1 gas system:

VACUUM IN CHAMBER

To make the vacuum in the chamber first is needed to be empty so recover Xe or evacuate Ar.

• Isolate the chamber from the gas system:
  • close V18 and V22 (the most important)
  • close V1 and V15
  • close V19
  • close V23
  • close V24
• Open the chamber to the vacuum pump:
  • Open guillotine valve
  • Open BV1 and BV3
  • Open BV2 and BV4
  • Switch on Vacuum pump
  • At 10-2 mbar , start turbo pump (On/Off button on the metalic box next to the pump) menu 398 rpm
  • Look to the Gauges

NOTE: Vacuum in mass spectrometer? We make the vacuum in the mass spectrometer section to allow us to use it as leak detector but we must isolate it for protection when we pressurize the chamber.

VACUUM IN GAS SYSTEM

• Isolate the chamber:
  • close guillotine valve
  • close BV1 and BV3
  • Switch off the pump
  • Before opening the gas system be sure there’s no gas in there. If there is something recover it or take it out by V25.
• Open the gas system:
  • open V24, V23, V21, V19.
  • Be sure that valves V2, V3, V4, V5, V6, V7, V8, V10, V12, V13, V19 are opened.
  • Be also sure that following valves are closed: V17, V11, V9, V25, V14, V16, V15, V1 (by now let it closed. We will replace P1 and P6), Getters valves G1 and G2.

• Switch on vacuum pump and proceed as before.

If you want to make the vacuum in both at the same time, just don’t isolate one from the other: keep BV1, BV3 and guillotine valve opened. But we will do the vacuum separately as we have explained.

TAKE OUT THE XENON

• Switch off the circulation pump.
• Put the recovery bottle (silver) inside the special chamber filled with liquid Nitrogen (15 cm).
• Open the bottle.
• Open V20.
• Control P5, when you get all that you want close V20
• Close the bottle
• Recover the liquid Nitrogen.

FILL IT WITH (NEW) XENON

• Be sure that all the gas system is opened in circulation mode.

Note: Be sure that the spectrometer is protected close BV4 and BV3

• Open Xenon bottle (blue).
• Open P1and adjust it.
• Open V15
• Fill the chamber up to the pressure you want. See: P2, P3, P4
• Close the V15, P1 and bottle

Note:To prevent over-pressure in P1, open it and V15 (with the bottle already closed) and let the gas go inside.

FILL IT WITH ARGON

The same procedure as wit Xenon but using Argon (yellow) bottle, P6 and V1

Note: to prevent overpressure in P6. With the bottle already closed, open P6 and V16 to let the gas go inside.

TO USE THE RECOVERED XENON

• Just open the bottle (silver), open V20, look at P5.
• Close V20, V17 and bottle.

-- NeXT - 22 Feb 2011