LLNL tandem mirror experiment (TMX) upgrade vacuum system

Journal Article · Thu Apr 01 00:00:00 EST 1982 · J. Vac. Sci. Technol.; (United States)

DOI:https://doi.org/10.1116/1.571513· OSTI ID:5648306

Pickles, W L; Chargin, A K; Drake, R P; Hunt, A L; Lang, D D; Murphy, J J; Poulsen, P; Simonen, T C; Batzer, T H; Stack, T P; Wong, R L

The tandem mirror experiment (TMX) upgrade is a large, tandem, magnetic-mirror fusion experiment with stringent requirements on base pressure (10/sup -8/ Torr), low H reflux from the first walls, and peak gas pressure (5 x 10/sup -7/ Torr) due to neutral beam gas during plasma operation. The 225 m/sup 3/ vacuum vessel is initially evacuated by turbopumps. Cryopumps provide a continuous sink for gases other than helium, deuterium, and hydrogen. The neutral beam system introduces up to 480 l/s of H or D. The hydrogen isotopes are pumped at very high speed by titanium sublimed onto two cylindrical radially separated stainless steel quilted liners with a total surface area of 540 m/sup 2/. These surfaces (when cooled to about 80 K) provide a pumping speed of 6 x 10/sup 7/ l/s for hydrogen. The titanium getter system is programmable and is used for heating as well as gettering. The inner plasma liner can be operated at elevated temperatures to enhance migration of gases away from the surfaces close to the plasma. Glow discharge cleaning is part of the pumpdown procedure. The design features are discussed in conjunction with the operating procedures developed to manage the dynamic vacuum conditions.

• Research Organization: Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 5648306
• Journal Information: J. Vac. Sci. Technol.; (United States), Vol. 20:4
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
TMX DEVICES
CRYOPUMPS
VACUUM SYSTEMS
ARGON
CARBON
DEUTERIUM
ELECTRON DENSITY
ELECTRON TEMPERATURE
GETTERS
GLOW DISCHARGES
HIGH VACUUM
HYDROGEN
IMPURITIES
LOW TEMPERATURE
METHANE
NITROGEN
OXYGEN
TITANIUM
WATER
ALKANES
ELECTRIC DISCHARGES
ELEMENTS
EQUIPMENT
FLUIDS
GASES
HYDROCARBONS
HYDROGEN COMPOUNDS
HYDROGEN ISOTOPES
ISOTOPES
LABORATORY EQUIPMENT
LIGHT NUCLEI
MAGNETIC MIRRORS
METALS
NONMETALS
NUCLEI
ODD-ODD NUCLEI
OPEN PLASMA DEVICES
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
PUMPS
RARE GASES
STABLE ISOTOPES
THERMONUCLEAR DEVICES
TRANSITION ELEMENTS
VACUUM PUMPS
700209* - Fusion Power Plant Technology- Component Development & Materials Testing