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Stock Company "NIIEFA," Russia, within the framework of the international project ITER produces and supplies the PF1 poloidal field coil. The choice of design solutions, materials, and technologies is under high electromagnetic and thermal loads. The PF1 coil uses liquid helium as a cooling system, which is fed into joints through helium inlets. Joints are bimetallic structural components obtained by explosion welding technologies and tungsten inert gas (TIG)-welding with a complex structural profile. Materials used: austenitic stainless steel, bimetallic copper-steel; bonded technology: TIG-welding, explosion welding. The quality of materials, explosion border and welds are subject to the highest requirements of European standards. Technologies of industrial manufacture of the PF1 coil require the use of nondestructive testing (NDT) procedures, caused by complex weld profile, small testing zone, and heterogeneity of welds. This paper shows the technology and NDT equipment for testing material and welds of the PF1 coil. [ABSTRACT FROM AUTHOR]

The PF1 coil manufactured in the Russian Federation is one of the six poloidal field (PF) coils of the ITER electromagnetic system. The PF1 winding represents a stack of eight double pancakes (DPs). Each DP is wound from niobium-titanium "cablein-conduit" conductors using the "two in hand" technique. The PF1 unidirectional winding is provided by connecting the ends of DPs into a single electric circuit by "shaking hands" low-resistance joints. An acceptance criterion formanufactured joints is an active resistance of less than 5 nΩ in the range of PF1 operating temperatures and applied magnetic fields. The initial joint design was updated on the basis of deviation requests of the ITER Organization. As a result, the previously developed techniques and tools were upgraded. To verify the modifications made, the preliminary joint sample was manufactured and tested in the NIIEFA test facility. Despite the limited current (up to 20 kA) and magnetic field, the results of the NIIEFA test verified the possibility of meeting the acceptance criterion and allowed us to start the manufacturing of the qualification joint sample. The final electrical test was performed in the "SULTAN" test facility of the Swiss Plasma Center (Switzerland). The test results are presented in this paper. [ABSTRACT FROM AUTHOR]

The ITER magnet system will operate in extremely severe conditions, which impose high requirements for mechanical and dielectric strength of the electrical insulation of the superconductive coils. Only monolithic structure obtained during the VPI procedure is capable to provide the required mechanical and dielectric strength for electrical insulation. To provide the qualitative insulation, a temperature non-uniformity of the electrical insulation should be kept within the range of [−5, +5 °C] and [−0, +20 °C] during filling with epoxy compound and its curing, respectively. The PF1 coil is about 150 t in weight and consists of materials with different thermal conductivity. Besides, a complicated geometry of the coil adds complexity to VPI. Since the VPI is usually a long-term and irreversible process (within pot life of compound), the whole process should be controllable. The paper describes the developed calculation model of the ITER PF1 coil and presents the results of numerical simulation of this model at VPI of electrical insulation. The completed VPI of the ITER PF1 coil has verified the proposed method for coil heating and proved an acceptable agreement between the calculated and measured temperature distributions throughout the VPI procedure. [ABSTRACT FROM AUTHOR]