Development of jacketing technologies for ITER CS and TF conductor

Hamada, Kazuya; Nakajima, Hideo; Matsui, Kunihiro; Kawano, Katsumi; Takano, Katsutoshi; Tsutsumi, Fumiaki; Okuno, Kiyoshi; Teshima, Osamu*; Soejima, Koji*

The ITER Toroidal Field (TF) coil and Central Solenoid (CS) use NbSn cable-in-conduit conductor. Conductor fabrication process are as follows; (1) Fabrication of jacket. (2) Butt welding of jacket to make a long tube (CS: 880 m, TF: 760 m) and insertion of superconducting cable into jacket. (3) Compaction of jacket. (4) Winding for transportation. JAEA has developed jacketing technologies in the cooperation with industries. Major achievements are as follows; (1) Full scale TF and CS jackets were fabricated using low carbon SUS316LN and boron added and high manganese stainless steel (JK2LB), respectively. The jackets satisfied ITER mechanical and dimensional requirement. (2) Butt welding condition was studied to obtain good internal surface condition of welded joint. (3) Compaction machine was constructed. As results of compaction test of TF and CS jacket, compacted jacket dimensions satisfied ITER requirement. Therefore, JAEA demonstrated jacketing technologies for ITER conductor.