Qualification process and quality control planning for JT-60-SA Toroidal Field coils construction

In the frame of the Broader Approach program, ENEA, the Italian agency for the renewable energies development, is responsible of the supply of nine Toroidal Field (TF) superconducting coils for the JT-60SA project, under the F4E general coordination of the overall European contribution. In this context a wide and innovative program for the qualification of the manufacturing processes and the quality control definition was developed and actualized from the beginning of the project. The first steps of the program were realized in the prototypes realization activities carried out so far, so allowing a first evaluation of its effectiveness and the consequent modulation. So in this work, after an account of the main already made activities and its results, an evaluation of the program and the experience gained until now is done. In particular a more detailed report is done about the special process involved in coil assembly and manufacture, whose complexity implies a multidisciplinary approach due to the different necessary technologies. In this regard, the main goal has been represented by the manufacture of the first double pancake (DP). Specifically, the He inlet inserts welding qualification permitted to set-up the tooling to properly weld the He inlet insert that constitutes one of the care neediest points in the coil design. Also a mock-up for the electrical joint and terminations has been manufactured to qualify the manufacturing process in view of the coil production. Furthermore on the steel casing side, two different mock-ups that simulate the straight and curved legs of the casing were produced and the relative manufacturing process was tested and evaluated. The objective of them was oriented not only through the casing manufacturer to let them acquire the necessary confidence in the construction of the components, but also to the coil manufacturers which are responsible for the coil insertion into the casing, casing closure welding, embedding, and final machining. All these aspects have been faced and are described in this paper.