Mechanical Design of JT-60SA Magnet System

Latest design of superconducting magnet system in JT-60SA is presented. This magnet system consists of the TF coils and PF coils (CS and EF coils). For this magnet system, stress analyses are systematically carried out to optimize the structural design. In the analysis of TF coil, it is clarified that jacket of conductor has significant strength under the designed electromagnetic (EM) load. In addition, coil case has margin of mechanical strength. For the PF coils, maximum stress appears at jackets of CS and EF conductor are less than 500 MPa, which is within fatigue limit. The latest design of CS support structure is very strong, because the no gap is made between CS modules even though total repulsive force of CS is maximum with no pre-compression. Therefore, optimization or simplification of structure design is possible for all magnet systems from the latest design in the detail design phase.