The ITER superconducting magnet system consists of 18 toroidal field (TF) coils, six central solenoid (CS) modules, six poloidal field (PF) coils and 18 correction coils. The National Institutes for Quantum and Radiological Science and Technology (QST), serving as the Japan Domestic Agency (JADA) in the ITER project, is responsible for the procurement of nine TF coils. Manufacturing of the first TF coil began in October 2013 and was completed in January 2020. While the basic technology for TF coil manufacturing has been developed through large-scale qualification trials, many additional issues were found when developing the first TF coil. Accordingly, these technical issues resolved and the TF coil was successfully completed. The technical issues and their solutions are reported in these special issues.
