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FUSE Large Vacuum Chamber

CASA-ARL Facilities Information

Large Vacuum Chamber

This chamber accommodates the optical testing of the approximately 2 meter high spectrograph. Dynavac Inc. was contracted to build the 11' D x 14' L vacuum chamber with pumping system and controls. The chamber was also designed to interface with a Newport Corp. vibration isolated optics table and integral isolation supports. A custom dolly, floating on air-bearing supports, is used for the loading/unloading of the optics table and for transporting the optics table and satellite about the cleanroom. 

In this photo, workers are installing a cold plate.  The "curtain 
rods" at the top of the chamber, the many ports, and one of the catwalks are visible.

Large Vacuum Chamber Features:
  • 11' D x 14' L horizontal vacuum chamber
  •  3ea. 20'' CTI cryopumps on 20'' gate valves
  • Roots blower/rough pump system with LN2 cold trap
  • Fully computer controlled with manual override
  • Many ports for electrical feedthroughs
  • Four special ports on top of the chamber
  • Custom designed platform for top of chamber
  • Pumping speeds
    • Atm. to low vacuum: 60 min.
    • Low vacuum to 1 x 10-6 Torr: 60 min.
  • Ultimate vacuum: 1 x 10-7 Torr
  • Empty chamber TQCM rate < 5 HZ/Hour
    • equivalent to 7 x 10-9 gm or a thickness of  2.2 Angst. per hour
  • Available LN2 cold plates
  • Internal mounting points
    • Rails on upper part of chamber
    • Mounting nuts at many locations
  • Personnel catwalk
  • 10' x 5' x 1' tuned stainless steel optics table
  • Special bellows feedthroughs for external isolation legs
  • Internal rails for insertion/removal of optics table
  • Special dolly for insertion/removal of optics table
  • TQCM's for monitoring contamination
  • RGA for monitoring contamination
  • Building GN2 for backfilling operations
  • EUV/FUV Light Source system