Mechanical study on the Japanese test coil for the large coil task

Mechanical study for the Japanese test coil for the Large Coil Task will be profitable for the construction of a superconducting tokamak coil system. For high rigidity of coil in the radial direction, high strength 304L stainless steel and full hard high strength copper stabilizer were chosen for the test coil. In the structural analysis of the test coil, unclear factors of the interaction mechanism between the winding and the helium vessel was excluded in order to design the test coil for the worst case condition. A mechanical verification test on the 304L stainless steel and the conductor were carried out. 304L stainless steel test results indicated that it is possible to level up design criterion. A test of the 0.2% yield strength of the full size conductor was 15% higher than the value used for the previous design.