Design of vacuum vessel for Aditya Upgrade tokamak

Aditya tokamak is a limiter tokamak device with a torus vacuum vessel having square cross section. The existing Aditya tokamak is being upgraded into a machine with divertor operation and good plasma control to support the future Indian Fusion program in a big way. The up-gradation of Aditya tokamak to diverter tokamak needs additional magnetic field coils for diverter operation, close to the vessel. To accommodate the coils, the existing vessel of square cross section will be replaced with a circular cross section. This vacuum vessel will be made up of stainless steel 304L. It is bakeable up to 150° C. The ultimate vacuum is ~ 10^-9 torr. Two numbers of identical semi torus will be assembled to torus shaped vessel. The end flanges of the semi torus are connected with sealing double Viton `O´ rings to form a torus. The major radius of torus vessel is 750 mm &inner radius is 305 mm. Its wall thickness is ~8 mm. The vacuum vessel will have 110 various sizes of ports/openings, including 4 tangential ports. The nonstandard ports like rectangular and triangular ports are blanked with wire seals. In this paper, the design of vacuum vessel for Aditya Upgrade tokamak is presented.