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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. [ABSTRACT FROM AUTHOR]

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 coilWPhas 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 ofmajor 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. [ABSTRACT FROM AUTHOR]

Superconducting high field magnets are tightly constrained in terms of field quality, since such magnets are usually designed to perform quite demanding tasks, such as focusing particle beams in accelerators, plasma confinement and shaping in fusion devices, and polarizing actions in magnetic resonance. In all these cases, small discrepancies of field map from the design values may strongly impact on device performance. As a consequence, quality insurance procedures are needed to verify if each single coil meets such criteria, e.g., using laser tracking, and possibly warm magnetic measurements. As a matter of fact, external magnetic measurements can be used to estimate the possible deformations of conductors inside the magnet, but this implies inverse problem approaches. The field probes accuracy is therefore critical, and the measurement system must be carefully designed, taking into account the probe characteristics, but also the characteristics of the windings and of the surrounding environment. In this paper, different measurement techniques are compared in terms of sensitivity and accuracy, with reference to various types of sensors and of measurement schemes. [ABSTRACT FROM PUBLISHER]

In August 2006, about 95% of the production of the 1232 LHC superconducting dipole cold masses, whose coils are wound with Cu/Nb-Ti cables, is completed. One of the 3 manufacturers, having produced one third of the required magnets, completed its production in the end of 2005. The acceptance of the magnets takes place after the 1.9 K performance tests and has been issued for more then 1000 magnets so far. More then half of the dipole magnets are already installed in the tunnel. The paper reviews the main features of the dipoles, the most important steps of the manufacturing and the most critical operations. The quality control and the critical non-conformities that have led, for instance, to a swift campaign of investigations and repairs of few subcomponents (diode assembly, cold bore tube to welding flare fillet weld) are discussed. The status of the production and the performance of the tested dipoles will be presented. Finally the expected schedule for the completion of the production will be shown. [ABSTRACT FROM AUTHOR]

More than 10% of the collared coils of the main LHC dipoles have been produced. In this paper we compare the measured field quality to beam dynamics targets using correlations to measurements at 1.9 K. The present status of field quality is given and corrective actions carried out to center field quality on optimal values are presented. Differences among the three manufacturers are analyzed, and the main results that concern correlation between cold and warm measurements are outlined. Present trends in the production and open points are discussed. [ABSTRACT FROM AUTHOR]