A few days ago, a sample of the joints connecting the double pancakes that form the winding packs of the toroidal field magnets, was shipped to the Sultan facility in Villigen (Switzerland).

The sample, designed and manufactured by ASG, is shown in Fig 1. The main objective of the campaign is to verify the performance of the joint: the electrical resistance of the joint, in dc current, at a temperature of 4.5K, with currents up to 42.5 kA and magnetic fields up to 3 T will be measured. The campaign also includes alternating current tests, both in the absence of a magnetic field and with fields up to 2 T. It should be noted that the performance of the conductors has already been successfully verified in the recent past.

SULTAN is the largest worldwide magnet facility designed to test, high current superconductors in an environment characterized by strong magnetic fields (up to 11 T).

SULTAN is a facility of the Center for Research in Plasma Physics (CRPP), one of the main scientific branches of the École Polytechnique Fédérale de Lausanne (EPFL, Switzerland).

The DTT experience will be invaluable for the design of the future DEMO from many points of view, including integration and assembly problems with the main components of the machine, such as vessel, first wall and cooling system.

Fig. 1 Sample of the DTT TFC-joint