DESIGN, FABRICATION AND TEST OF DOUBLE-WA LL VACUUM VESSEL FOR JT-60U

A double-wall vacuum vessel was designed and fabricated for JT-60U(an upgraded machine of JT-60), which has a plasma current up to 6MA and a large plasma volume(100 m3). A new concept of Inconel 625 all-welded structure was adopted to the vessel, that comprises an inner plate, sq uare tubes and an outer plate. The vacuum vessel with a multi-arc D-sh aped cross section was fabricated by using hot-sizing press. The elect romagnetic and structural analysis has been performed for plasma disru ption loads. Dynamic responses of the vessel were measured during plas ma disruptions, and the observed displacement had a good agreement wit h the result of FEM analysis.