The ITER central solenoid (CS) components are currently being manufactured. This Nb3Sn superconducting magnet will provide the magnetic flux swing required to induce up to 15 MA as plasma current. It includes six identical coils, called modules, stacked on top of each other to form a solenoid, enclosed inside a structure split into nine subsets, to provide vertical precompression and mechanical support. High mechanical stresses in materials and high voltages call for the use of structural materials with high strength and toughness and high dielectric strength insulating materials, respectively. The pulsed operation imposes materials with high fatigue strength at cryogenic temperatures. Unlike for the structure, where large existing manufacturing tools were usable, the modules required the construction of a dedicated manufacturing line. A comprehensive qualification programme is performed at the manufacturers before applying procedures for the production of the CS components. The main characteristics of the CS components, their manufacturing routes and the different elements of the qualification programme are described. The overall plan for the manufacture is reported. The status of the first series production components manufactured is presented as well as the planned delivery schedule to the ITER site.

The uniqueness of the ITER fusion project drives purpose and scope here to fulfil (functional) Procurement Arrangement (PA) requirements for the Central Solenoid (CS) and Correction Coil (CC) magnets' electrical insulation [1-3]; as used and undertaken for covering high voltage testing operations of the magnet coil winding pack (WP) vacuum pressure insulation (VPI) beam qualification, followed in 2016 by start of magnets series production in the USA and China [1, 2]. Useful to be considered common state-of-the-art electrical power components testing practices [3, 4] are presented here as performed to verify that the integrity and insulation of the various components are within acceptable limits during different phases of the fabrication and to certify acceptance on delivery of the complete coils. Initial measurement plans were complemented into electrical tests with typical high voltage engineering implemented measures as a pre-requisite to successfully validate produced results. The above permitted the first quantitative validation of the obtained final production, including life time behavior.

The central solenoid (CS) is a key component of the ITER magnet system to provide the magnetic flux swing required to drive induced plasma current up to 15 MA. The manufacture of its different subcomponents has now started, following completion of the design analyses and achievement of the qualification of the manufacturing procedures. A comprehensive set of analyses has been produced to demonstrate that the CS final design meets all requirements. This includes in particular structural analyses carried out with different finite-element models and addressing normal and fault conditions. Following the Final Design Review, held in November 2013, and the subsequent design modifications, the analyses were updated for consistency with the final design details and provide evidence that the Magnet Structural Design Criteria are fully met. Before starting any manufacturing activity of a CS component, a corresponding dedicated qualification program has been carried out. This includes manufacture of mockups using the real manufacturing tools to be tested in relevant conditions. Acceptance criteria have been established for materials and components, winding including joints, cooling inlets and outlets, insulation, precompression, and support structure elements.

The Final Design of the Central Solenoid (CS) of the ITER Magnet system is currently being completed by the US ITER Domestic Agency (USDA) and the manufacturing line of the coil under installation at the supplier's premises in the USA. The Central Solenoid includes 6 identical Nb3Sn coil modules independently powered and enclosed inside a precompression structure preventing their separation. The CS structure includes 9 subsets, made of Nitronic 50 high strength austenitic stainless steel, evenly distributed around the stack of the 6 modules.

The manufacturing line of the ITER Correction Coils (CC) at ASIPP in Hefei (China) was completed in 2013 and the manufacturing line of the ITER Central Solenoid (CS) modules is under installation at General Atomic premises in Poway (USA). In both cases, before starting production of the first coils, qualification of the manufacturing procedures is achieved by the construction of a set of mock-ups and prototypes to demonstrate that design requirements defined by the ITER Organization are effectively met. For each qualification item, the corresponding mock-ups are presented with the tests to be performed and the related acceptance criteria. The first qualification results are discussed. (C) 2015 ITER Organization. Published by Elsevier B.V. All rights reserved.

After several years of design optimization, the Central Solenoid (CS) of the ITER Magnet system is now moving towards manufacture. The design has evolved to take into account on one hand the results of the R&D carried out by the US ITER team in charge of the development of the design and on the other hand the feedback provided by the involvement of industry in preparation of the manufacture. To address specific issues, dedicated mock-ups have been manufactured and tested. Electromagnetic, structural and thermo-hydraulic analyses have been carried out to verify the compliance of the design with the ITER design criteria. A review of the Final Design is planned in 2013, preparing then to move into the manufacturing phase.

The Central Solenoid (CS) of the ITER Magnet system is split into six independently powered coils enclosed inside an external structure which provides vertical precompression thus preventing separation of the coils and acting as a support to net resulting loads. The analyses include an assessment of the mechanical behavior of the different components of the CS, under the normal and fault conditions, aiming at demonstrating the ability of the CS to achieve 30 000 cycles of plasma operation at nominal current (15 MA). A comprehensive material testing program is developed for the conductor jacket, the impregnated glass-epoxy insulation and the structure. The paper describes the architecture of the analysis and qualification programs and provides an overview of the results obtained so far.

The Central Solenoid (CS) of the ITER tokamak has to provide the flux variation needed to induce the plasma current and to shape the field lines in the divertor region. It is designed as a stack of 6 identical coils, independently power supplied. Repulsing forces arising between the coils during a scenario are withstood by a precompression structure installed around the coils. Studies were carried out to simplify the winding manufacture, to optimize the precompression structure and procedure, to optimize the stack assembly of the 6 coils and the assembly of the central solenoid inside the tokamak which allows withdrawal from the machine, while meeting the ITER design criteria and in particular the Magnet Structural Design Criteria (static and fatigue).

The ITER Magnet system consist of 4 sub-systems, i.e. 18 Toroidal Field Coils (TF-coil), a central Solenoid (CS), 6 Poloidal Field Coils (PF-coil) and 3 sets of Correction Coils (CC). The Central Solenoid contributes a) to the inductive flux to drive the plasma, b) to the shaping of the field lines in the divertor region and to c) the vertical stability control. The CS performance is fatigue limited, mainly by the stress levels in the conductor jacket and in the pre-compression structure needed to keep the modules in contact as much as possible during the repulsive forces which can arise in operation. The choice of the jacket material and its impact on the pre-compression structure have been investigated by performing finite element analyses with 2D/3D global and local models. A large number of loading conditions and two material options for the pre-compression structure have been considered. The results obtained are used for the structural assessment (static and fatigue) resulting in the present baseline design.

The central solenoid (CS) of the ITER tokamak contributes to the inductive flux to drive the plasma, to the shaping of the field lines in the divertor region and to vertical stability control. It is made of 6 independent coils, using a Nb3Sn cable-in-conduit superconducting conductor, held together by a vertical precompression structure. This design enables ITER to access a wide operating window of plasma parameters, up to 17MA and covering inductive and non-inductive operation. Each coil is based on a stack of multiple pancake winding units to minimise joints. A glass–polyimide electrical insulation, impregnated with epoxy resin, is giving a high voltage operating capability, tested up to 29kV. The CS performance is fatigue driven mainly by the stress levels in the conductor jacket and in the precompression structure needed to keep the modules in contact during the repulsive forces which can arise in operation. A rigid connection to the TF coils provided at one end and a centering support at the other end allow to resist net vertical forces as well as unbalanced radial forces while avoiding torsion transmission from the TF Coils to the CS assembly.

The detection of new physics signals at the highest luminosities available in proton-proton collisions at LHC requires identification and precise measurement of muons, photons and electrons. Toroidal and solenoidal fields were considered at the beginning of the design. For the CMS detector, the choice of a compact design led to the choice of a strong magnetic field. The most practical magnet that can generate a strong magnetic field is a solenoid. A long (about 13 m) superconducting solenoid of large radius generating a magnetic field of 4 T guarantees good momentum resolution. The magnetic flux is returned via a 1.8 m thick iron yoke of a weight of 12 000 tonnes. The magnetic stored energy is 2.52 GJ and the coil total weight is 500 tonnes. The coil main design features are indirect cooling, pure aluminium stabilisation and mechanically reinforced conductor. It is a four layer winding, composed of 4 axial sections bolted together.

A prototype twin superconducting quadrupole magnet for the Large Hadron Collider (LHC) is being developed and built at CEN/Saclay in collaboration with CERN. This paper describes the mechanical tests performed to validate the main concepts of the mechanical design in order to meet the requirements of prestress while maintaining a precise geometrical shape of the coils. Moulding tests on samples of superconducting cables have been made in order to evaluate the final size of the coils after curing and under stress. Collaring tests have been made on small length models to verify the process and the resulting prestress. The principal results and conclusions of the tests are summarized

Within the framework of the Large Hadron Collider (LHC) R&D program, CERN and CEN/Saclay have established a collaboration to carry out, amongst others, the design, building, and testing of a superconducting LHC prototype quadrupole at the Saclay laboratory. The twin aperture prototype, working in liquid helium at 1.8 K, has a gradient of 250 T/m, is about 3.2 m long, with a coil aperture of 56 mm. This paper describes the present state of the R&D work for the quadrupole magnet, reviewing the fabrication and validation tests of the design.< >

As part of a collaboration with the SSC, CEA/Saclay has designed superconducting quadrupole magnet for the High Energy Booster ring. A number of prototypes are being built at Saclay, after which the production will be handed over to an American firm. This paper presents the mechanical, thermal and electromagnetic analyses which have been performed during the design of the magnet.<>

Within the framework of the LHC R&D program, CERN and CEA/Saclay have established a collaboration to carry out, amongst others, the design, building and testing of a superconducting LHC prototype quadrupole at the Saclay laboratory. The cold mass of this quadrupole is presently under construction at Saclay. The quadrupole design features a twin aperture configuration, a gradient of 250T/m, a length of 3m and a free coil aperture of 56mm. European industries participate in this project by delivering components and fabricating the tooling according to specifications prepared by Saclay. This paper gives details of the magnet design and construction. Coil winding will start in summer 1991 and the first prototype should be assembled and ready for testing by mid 1992.