LLNL tandem mirror experiment (TMX) upgrade vacuum system

Journal Article · Thu Apr 01 04:00:00 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 Laboratory, University of California, Livermore, California 94550
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 5648306
• Journal Information: J. Vac. Sci. Technol.; (United States), Journal Name: J. Vac. Sci. Technol.; (United States) Vol. 20:4; ISSN JVSTA
• Country of Publication: United States
• Language: English

Related Subjects

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