Testing materials and tooling to manufacture one of ITER’s magnets

The ITER machine will use powerful superconducting magnets – Poloidal and Toroidal field coils – to confine its burning plasma. In the form of concentric circles, the six PF coils will entrap the hot gas from top to bottom to control its shape and stability. Europe is responsible for five of the PF coils, of which one will be manufactured in China, and the remaining coil will be produced in Russia.

In China’s Institute of Plasma Physics (ASIPP) the qualification activities, which for the time being consist of testing tooling and materials used at the prototyping phase, have kicked off and the results have been overall positive. This phase is of critical importance because it allows engineers to spot potential manufacturing problems and introduce improvements so that the final coils are in line with the specifications. The welding of the second sample of the helium inlet, the entry point of the gas running through each magnet to reach the freezing cold temperatures, has been successfully qualified and passed the leak test. The tooling for the dummy joint boxes, the equipment that will be used to connect the lengths of conductor with power feeders, has been accepted.

Electrical high voltage testing will soon be carried out on a 2 metre 3×3 dummy coil and two more 720 m conductors have been accepted raising to 30% the volume of material needed for manufacturing. The testing of the de-spooling unit, which will be used to gently unwind the conductor before it gets wound again in the form of the coil, has also been successfully tested. Last but not least, the metallic structure upon which the “Double Pancakes”- layers of insulated and impregnated conductor stacked together- will rely on during manufacturing has been tested to make sure that it can support their weight.

Apart from the technical progress there has also been an administrative milestone. The F4E auditors visited the ASIIP facility and during four days carried out a thorough review of all processes, handling of raw material, documentation and standards. The outcome of their analysis suggested that the facility met all criteria and was in conformity with all requirements.