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The highly innovative process, proposed by CNIM and chosen by F4E, is based on a pultrusion technique that involves the manufacture of profiles of epoxy S2-glass. Each pre-compression ring (PCR) is manufactured by winding the flat pultruded profile (2 mm thick and about 2800 m long) and utilizing an adhesive tape (0.12 mm thick) between layers to freeze the geometry. After the curing cycle, the PCR is machined to reach the required geometry tolerances. Each PCR will have a diameter of approximately 5 m, a cross-section of 332 mm × 288 mm and will weigh approximately 3 tons. The PCRs will finally be proof tested at 600 MPa in hoop stress that corresponds to 1.5 time the operational hoop stress. An extensive qualification phase has been released to prove that both materials and manufacturing technology can procure PCRs according to requirements. This paper describes the manufacturing processes, the results of the qualification phase and the status of the production.

The plasma confinement of the International Tokamak Experimental Reactor (ITER) is provided by the magnetic field generated by 18 toroidal field coils. Fusion for Energy (F4E), the European Domestic Agency for ITER, is responsible for the supply of 10 TFC to ITER project. Their procurement has been divided into three main work packages: I) the production of the radial plates, structural stainless steel components housing the Nb3Sn conductors, II) the manufacture of 10 Winding Packs (WP) and III) the cold test of 10 WP plus their insertion into the Coil Cases. This article gives an update of the status of the production of the third and last work package performed under the framework of an F4E contract assigned to SIMIC SpA, an Italian company. In particular, the details of the WP thermal cycle, the insertion of the firsts TF coil in their coil cases, the closure weld, the gap filling and the machining strategy adopted to optimize the final TF coil shape optimized to minimize the field errors are presented.

The magnetic field, necessary for the plasma confinement in the International Thermonuclear Experimental Reactor (ITER), Cadarache, France, is provided by the 18 Toroidal Field Coils (TFC). In each coil, this magnetic field is produced by circulating a current of 68 kA through 4.5 km of Nb3Sn cable-in-conduit superconductor, which is assembled into a mechanical structure capable of withstanding the huge Lorentz forces produced. The Fusion for Energy, the European Domestic Agency for the ITER, is responsible for the supply of 10 TFC. This article gives an overview of the manufacturing and test processes applied during the series production of all sub- and final assemblies, as well as the production status. Special emphasis will be put on some particular characteristics of the Nb3Sn superconductor and other problems faced during manufacturing and strategies applied to overcome them.

The first European superconducting winding pack (WP) and the first set of coil cases [toroidal field coil cases (TFCC)] for ITER are going to be delivered in 2017. The TFCC are steel structures that provide structural integrity to the WP, contribute to neutron shielding capacity, provide support to operating forces, and offer interface connections with the rest of the ITER machine. The TFCC assembly is formed by four main parts: two sectors with U-shaped section and two closure plates, which, after being welded together, enclose the WP. Each TFCC weights about 150 t and presents a wall thickness from 60 to 120 mm. The presence of distortions when welding such thick structures is particularly problematic in these components, which require tight tolerances and include several interfaces with other parts of the machine. In order to compensate the distortions, extra material is present in the critical areas to allow postwelding machining. The amount of extra material has to be optimized to reduce machining time and therefore the cost of the manufacturing. Thus, the evaluation of the welding-caused distortions is essential in order to confirm the extra-material strategy. In this scenario, an experimental and simulation campaign has been set up to predict the deformation of the TFCC during welding. First, welding coupons were welded in representative configurations. Then, these data were used to build a preliminary finite element method (FEM) model tool, using ANSYS software, which was then benchmarked against a “blind test” coupon and three TFCC-like mock-ups of 1-m length. Finally, a full FEM model was constructed using the previous outputs and is currently under assessment to predict the deformation of the TFCC during the welding process. This paper presents the numerical and experimental activities carried out so far, being EnginSoft S.p.A. the developer of FEM models, SIMIC S.p.A. the responsible of welding processes and data acquisition, and Fusion for Energy the contractual and technical supervisor.

The International Thermonuclear Experimental Reactor (ITER) magnetic system includes 18 toroidal field (TF) coils constructed using Nb3Sn cable-in-conduit superconductor. Each TF coil comprises a winding pack (WP) composed of seven double pancake modules stacked together, impregnated and inserted into a stainless steel coil case. Ten TF coils are being produced in Europe, under the responsibility of Fusion for Energy (F4E, the European Domestic Agency), while the remaining nine TF coils are being produced in Japan. F4E has implemented a strategy dividing the procurement into three packages. One is related to the construction of 70 radial plates (RP), another to the fabrication of 10 WP, and a third to the cold test and coil-case insertion of 10 WP. After 7 years of R&D and qualification activities and of industrial production, the first ITER TF coil WP has been completed in Europe. Factory acceptance tests, including leak, dimensional, and electrical tests at room temperature, were completed in May 2017 and the series production of the remaining nine TF WPs in Europe is underway. The first package has been completed and all 70 RP have been delivered. Commissioning of major tooling for the third package is to be performed at the end of 2017. In this paper, we report on the test of the first TF WP and on the status of the remaining production.