Design and analysis of the DIII-D vacuum vessel

Conference · Sun Dec 01 04:00:00 EST 1985

OSTI ID:6451807

Gallix, R; Baxi, C B; Hoffmann, E H; Lightner, S; Miller, J E

A key component in the recent modification by GA Technologies (GA) of its Doublet III tokamak to its current DIII-D configuration is the new dee-shaped vacuum vessel. Inside dimensions of the minor cross section are 2.85 m height, 2.43 m outer radius, and 1.47 m width, giving a 37 m/sup 3/ interior volume. The vessel is a single Inconel 625 weldment with 25 to 38 mm thick walls, mostly of sandwich construction with corrugated core. Four 76 mm diameter radial pins support and center the 9 metric ton vessel at mid-height. The vessel has 195 welded-on ports which provide access for pumping, plasma heating, diagnostics, limiter actuators, and maintenance. The ports are single-walled weldments of about 45 different sizes and shapes. They have a total of 215 bolted flanges with diameters up to 673 mm, using either Conflat or Helicoflex metallic seals. The vessel is thermally insulated and capable of being baked out at 400/sup 0/C by 60 Hz induction heating combined with circulating 1 kg/s of hot air through the vessel wall corrugations and through brazed tubes and welded channels on the outside of the ports. During plasma operation, the average heat flux to the vessel walls is 25 W/cm/sup 2/ and cooling is achieved by running water through the air passages. The structural analysis evaluates the effects of mechanical loads (e.g., dead weight, seismic loads, vacuum, air and water pressure); magnetic loads induced by coil faults and 5 MA plasma disruptions; and thermal loads due to bakeout and plasma shots. The resulting stresses are combined and checked against allowables based on ASME B and PV code criteria.

• Research Organization: General Atomics Co., San Diego, CA (USA)
• DOE Contract Number: AC03-84ER51044
• OSTI ID: 6451807
• Report Number(s): GA-A-18173; CONF-851102-118; ON: DE87010910
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700209* -- Fusion Power Plant Technology-- Component Development & Materials Testing
ALLOYS
CHROMIUM ALLOYS
CLOSED PLASMA DEVICES
CONTAINERS
COOLING SYSTEMS
DESIGN
DOUBLET-3 DEVICE
ENERGY SYSTEMS
ENERGY TRANSFER
HEAT TRANSFER
INCONEL 625
INCONEL ALLOYS
IRON ALLOYS
MOLYBDENUM ALLOYS
NICKEL ALLOYS
NICKEL BASE ALLOYS
NIOBIUM ALLOYS
PRESSURE VESSELS
STRESSES
TANTALUM ALLOYS
THERMAL STRESSES
THERMONUCLEAR DEVICES
THERMONUCLEAR REACTOR COOLING SYSTEMS
TOKAMAK DEVICES