Fabrication of the KSTAR vacuum vessel and ports

The construction of the steady-state-capable superconducting KSTAR tokamak is in close proximity to the finalization. As one of the main components of the KSTAR device, the vacuum vessel is designed and manufactured during the construction period. The KSTAR vacuum vessel is composed of two large sectors forming the 337.5° of a full torus, and the remaining 22.5° section consisting of 24 small pieces. The large two sectors were welded at the site, and the 22.5° space was used for toroidal field coil assembly. The remaining 22.5° section of the vacuum vessel was assembled after 16 toroidal field coils assembly. The total 72 penetration ports were used to connect the vacuum vessel body and the cryostat. The major fabrication activity started in January 2003 after the finalization of fabrication design. The final components and structures were warehoused in June 2004 and site assembly is finished in 2007. Details of analysis, shop fabrication, and inspection results of the vacuum vessel including ports are summarized in the present work.