Design progress of the vacuum vessel for ITER

Recent design progress of the vacuum vessel for the International Thermonuclear Experimental Reactor is presented. A structural design strategy has been developed for the VV in which the VV will be designed, fabricated, and tested per the requirements of the ASME Code Section VIII, Div. 2. The inboard structure that was originally designed polygonal cylinder has been modified to a cylindrical shape in order to resist the induced forces due to the fast current discharge of the TF coil. The shielding material under the TF coils in the upper outboard region has been changed to a ferromagnetic material (SS 430) instead of SS 30467 to reduce toroidal field ripple. The thermal and hydraulic analyses indicate sufficient heat removal capability from the VV. Although detailed design modifications continue to be made to reinforce areas of high stress and to accommodate interfaces with other systems, problems completing the design from a structural standpoint are not anticipated.