抄録
JT-60 is planned to be upgraded to a JT-60SA superconducting tokamak machine. This project is the JA-EU satellite tokamak program under both broader approach and Japanese domestic programs. The JT-60SA tokamak is composed of the following main components: vacuum vessel (VV), thermal shield, superconducting coils (toroidal field coil, equilibrium field coil, and central solenoid), cryostat, and heating facilities. The VV has a D-shaped poloidal cross section and a double-wall structure to ensure high rigidity and toroidal one-turn resistance simultaneously. The material of the VV is 316L stainless steel with a low cobalt content of <0.05 wt%. Before the start of manufacturing the VV, fundamental welding R&D was performed to study the manufacturing procedures. The manufacturing procedures were successfully established with a trial manufacturing of 20 degree upper half of the VV. Based on the results, the actual VV manufacturing has started in November 2009.
