The sixth poloidal field superconducting coil (or PF6 coil), the heaviest of all six superconducting magnet coils of the International Thermonuclear Fusion Experimental Reactor (ITER) project, was successfully installed at the bottom of the tokamak pit at the ITER site in France on April 21 local time. The installation was supervised by Fusion for Energy, marking another international collaboration moment.

This magnet is also known as the “divertor coil.” Its main function is to create the null field point that allows the removal of helium ash from plasma.

The sixth poloidal field superconducting coil successfully sits at the bottom of the tokamak pit. [Image: iter organization]

The magnet consists of nine twin-shaped winding pancakes and a series of supporting accessories, each measuring 11.2 meters in diameters and weighing roughly 400 metric tons (heavier than two Boeing 747 airplanes). The profile accuracy of the PF6 coil is strictly controlled within ±1.5mm after winding.

A team of experienced engineers from the Institute of Plasma Physics, Hefei Institutes of Physical Science (ASIPP, HFIPS) worked on-site to help position this equipment in the correct place. As one of the contractors of ITER, ASIPP has sent many groups of experts overseas in the past few years, contributing their knowledge and effort to the ambitious international scientific project.

The PF6 is the heaviest of all six superconducting magnet coils of ITER. [Image: iter organization]

According to Alessandro Bonito-Oliva, the Magnets Programme Manager at the European Domestic Agency’s Fusion for Energy, the project is a “collective achievement of Europe and China, working together with the ITER Organization to manufacture a first-of-a-kind component that presented a number of technical and organizational challenges.”

The PF6 coil was manufactured in China by ASIPP. In March 2020, the coil was transported to Cadarache, France where ITER is located. The coil arrived in June after a sea journey of more than three months.

Source: Hefei Institutes of Physical Science,

Chinese Academy of Sciences