Bottom ring magnet completes all testing

Poloidal field coil #6 (PF6) is a 400-tonne magnet, the heaviest in a series of six ring magnets that will be installed outside of the vacuum vessel and toroidal field coil superstructure to influence the shape of the plasma and contribute to its stability by "pinching" it away from the walls.

Under an agreement signed with the European Domestic Agency Fusion for Energy, responsible for this ring magnet and four others, PF6 was fabricated by the Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP). Fusion for Energy and ASIPP teams have been collaborating since 2016 on the fabrication, from qualification activities, to pancake winding and impregnation, successful factory acceptance testing, and finally transport to the ITER site. The final fabrication step was thermal testing in the on-site European Poloidal Field Coils Winding Facility verify how the magnet responds under thermal contraction generated by ultra-cold and to conduct global leak, electrical and high voltage tests.

During thermal testing, the coil was inserted into a dedicated cryogenic chamber and cooled down to approximately 80 K (-193 °). Three full cooldown and warmup cycles were performed, each one requiring approximately one month.

Read the full report on the Fusion for Energy website.