Contracts were awarded this summer to the companies that will carry out the repair/refurbishment of the ITER thermal shield and vacuum vessel sectors. Teams deployed on site are already executing the first steps of the campaign. One year ago, the first of nine vacuum vessel sector modules (#6) had been transferred in the Tokamak pit and two others (#7 and #8) were in preparation in sub-assembly tooling in the Assembly Hall, where the 440-tonne sectors were being matched with thermal shield panels and toroidal field coils. The discovery of major defects in two of the components making up these sector modules brought vacuum vessel sub-assembly works to a halt and mobilized resources inside the ITER Organization to identify the root causes of the defects and to explore different repair options. The ITER team worked with experts from the ITER Domestic Agencies, professional organizations from the ITER Members, and research institutes such as CEA, CERN and professional welding institutes to arrive at its final strategy, and with industrial partners to test its assumptions through mock-ups and trials. The repair campaign would be handled under three separate contracts—one for the repair of thermal shield panels, a second for the manufacturing of new thermal shield panels, and a third for vacuum vessel bevel repair. Working in close collaboration with the technical and legal teams, the ITER Procurement & Contracts Division was able to launch restricted tenders early in 2023, and conclude all negotiations in time to meet the tight schedule established by ITER management. The vacuum vessel thermal shield, which confines the radiation heat load from the vessel and keeps it from being transferred to the magnets operating at 4.5K, is actively cooled by gaseous helium running through a network of cooling tubes welded to the panels. After 'stress corrosion cracking' was identified on three sets of panels—and determined to be a likely risk for the others—the decision was made to replace the cooling fluid pipes on all nine sets of vacuum vessel thermal shield. 'The structural integrity assuring the leak-tight configuration of these pipes—all 23 kilometres of them—is critical because gases and liquids will find the tiniest breach in a structure under vacuum,' explains Sergio Orlandi, Head of the ITER Construction Project. 'Even submicron cracks can alter vacuum quality and degrade machine performance.' Two strategies were established by the expert groups. For thermal shield sectors showing no sign of stress corrosion cracking, the panels could be repaired. Repair would entail dismantling the sets into individual panels, removing all cooling pipes, grinding and polishing to remove the silver coating from the surface and to remove up to approximately ~3mm of base material from the panels in the area of the cooling pipes, and  finally re-attaching new pipes with stitch welding (and without silver coating). For thermal shield sectors already compromised by damage, complete re-fabrication was the preferred option. For both contracts, companies would be responsible for developing the methods and practices to achieve ITER requirements. The ITER Organization is supplying the new pipes. Dimensional non-conformities were found in the bevel (field joint) region of the three vacuum vessel sectors that have been delivered to ITER (#6, #7 and #8), with particularly severe variance against nominal geometry in sector #8. Left unrepaired, these non-conformities would compromise the access and operation of the bespoke automated welding tools planned for the in-pit welding of the sectors. The ITER Organization approach to repair is to re-work the bevels through a combination of building up material through manual welding and shaving excess material down through machining. 'From the start, our investigation teams stressed the importance of preferring machining over build-up wherever possible in order to minimize build-up as a whole. This is because added material is more susceptible to welding defects generating shrinkage in the sectors' configuration. That is a first important element of our repair strategy for the vacuum vessel,' says Orlandi. 'The second is that we need to take an integrated approach in the investigation of adjacent sectors' geometry. Instead of considering a sector's geometry only against its nominal manufacturing drawings, we have to consider each sector's configuration in relation to the adjacent sectors on either side to which it will be jointed through spliced plates with automatic welding.' This approach informed the technical specifications that were prepared for the restricted tender. The ITER Organization has formed dedicated task force (also involving specialists in the European Agency Fusion for Energy) that has all of the requisite competencies to follow, control and manage the repair works. The ITER Newsline will be meeting with this team in the coming days and weeks to produce a photo reportage on repair activities underway.

In August, Japan's National Institutes for Quantum Science and Technology (QST) and supplier Mitsubishi Heavy Industries shipped a spare toroidal field coil to ITER—the very last (of nine) D-shaped coils to be supplied by Japan to the ITER Project. On 23 August 2023, the spare coil left Mitsubishi's Futami plant for transport by barge to the port of Kobe. The 300-tonne component was loaded onto an oceangoing vessel in early September, for arrival in France later this month.  This milestone marks the end of an important industrial effort in Japan that began in 2005 when QST launched R&D for toroidal field coil manufacturing, and that gained steam when a Procurement Arrangement was signed with the ITER Organization in 2008 for the supply of 9 complete toroidal field coils (an assembly of winding packs and coil structures) and all 19 toroidal field coil structures. Working in collaboration, QST and Mitsubishi Heavy Industries developed high-precision technology for winding the niobium-tin conductors that form the heart of the superconducting winding pack, as well as durable structural materials for the coil cases. To arrive at manufacturing methods that would counter deformations caused by welding, parameter tests were conducted, and the welds verified using both miniature and full-scale specimens. Ultimately, through advanced welding procedures and machining techniques, Mitsubishi was able to meet the stringent requirements demanded for ITER. QST collaborated with Mitsubishi Heavy Industries, Mitsubishi Electric Corporation, Hyundai Heavy Industries, and Toshiba Energy Systems & Solutions Corporation for the full scope of the Procurement Arrangement. Mitsubishi Heavy Industries manufactured the inboard coil structures for all 19 coil cases and performed the final assembly (coil insertion and case closing) for 5 toroidal field coils, including the first coil to be completed for the ITER Project (January 2020) and the final, spare coil (TF19) that was completed last month. The coil is expected to reach France in late September and the ITER site in October.  See the Mitsubishi press release in English here. 

For the ITER community in France, Roger Pizot, who passed away on Sunday 23 July, was more than the long-standing mayor (1995-2020) of Saint-Paul-lez-Durance, the small village in Provence where ITER is located administratively. He was a friend and a partner. In 2001, as the ITER Final Design Report was being finalized and France was already intent on hosting the project, Mayor Pizot played a key role in marshalling the support, both political and financial, of local governments in Provence. As the long-time neighbour of CEA-Cadarache, one of France's largest nuclear research centres, he knew from experience the benefits that a major scientific institution could bring to its environment. On his initiative, the local governments of the Sud-PACA region would pledge close to half a billion euros to ITER—a sum equivalent in value, at the time, to the contribution of an ITER Member. Like many in his time and place, Mayor Pizot had left school early but retained, throughout his life, a vast curiosity for the world around him that led him to understand the importance of science exploration in general and of fusion research in particular. In 1959, the creation of a large CEA research centre in Cadarache, an uninhabited section of Saint-Paul-lez-Durance (pop. 900), had brought pride, jobs and prosperity to the poor and sleepy community. Half a century later, ITER placed the village under an international spotlight and promised renewed opportunities. In Mayor Pizot's words, Saint-Paul had become the improbable 'world capital of the atom.' In 2008, he confided to the ITER Newsline that he intended to 'serve ITER as ITER is serving Saint-Paul.' And serve he did: an industrial park was created at the village entrance to accommodate ITER contractors, along with a small commercial centre in the heart of the village with shops and restaurants to cater to their employees. Mayor Pizot's interaction with ITER took on an extra dimension in 2009 when he was appointed president of the newly created Commission locale d'information, an independent body that acts as an interface between a nuclear installation and the public in France. When ITER moved to its permanent headquarters in 2012, he initiated a tradition that his successor at the town hall in Saint-Paul has perpetuated: the gift of a large Christmas tree ever year symbolizing the strong, family-like relationship between ITER and the local community. The passing of Mayor Pizot at age 76 fills ITER with sadness. He will be remembered as a generous, efficient and no-nonsense associate to the project.

New 'bridges' spanning the main boulevard of the ITER platform, massive structures progressively donning their final attire, buildings in the last stages of civil works rising like pyramids ... thirteen years into construction, the ITER scientific installation is acquiring its near-final appearance. Despite the heat waves of July and August, progress made over the summer is observable in every corner. Some of it is spectacular, some of it barely perceptible but no less significant. For a full visual tour, view the photo gallery below.  

After designating 2022 as the "International Year of Basic Sciences for Sustainable Development (IYBSSD)," the United Nations (UN) General Assembly has now proclaimed 2024 to 2033 as the "International Decade of Sciences for Sustainable Development (IDSSD)," acknowledging the imperative to "create bridges accross scientific disciplines and knowledge forms in order to address the complex and intricate challenges of our time." Recognizing that developing countries face specific challenges in accessing new sciences and technologies, the resolution—proposed by Argentina, Cuba, Equatorial Guinea, Guatemala, Honduras, Hungary, Serbia, South Africa, Spain and Vietnam—proclaims the International Decade of Sciences for Sustainable Development represents "a unique opportunity for humanity to use the critical role that sciences play in the pursuit of sustainable development in its three dimensions as one of the key means of implementation as well as in responding to the complex challenges of our time to ensure a safe and prosperous future for all." The ITER Organization is one of many scientific organizations that supports the IYBSSD. Read the UN declaration in English here.

JET, the Joint European Torus in Culham, Oxfordshire (UK), has just kicked off a third and final campaign in deuterium and tritium. The planned experiments, known as "DTE3," will run for seven weeks and focus on plasma science, materials science, and neutronics. This campaign comes just 20 months after JET demonstrated sustained fusion over five seconds at high power and set a world record. In June, JET celebrated 40 years of science. JET's research findings have been critical to planning at ITER, as well as to that of the UK's prototype fusion powerplant STEP, the European DEMO prototype fusion plant, and other national laboratory and private projects around the world.   Repurposing and decomissioning activities on JET are scheduled to begin in 2024.  See the announcement on the UKAEA/Culham Centre for Fusion Energy website.

For the third year in a row, the Department of Physics at the Technical University of Denmark (DTU) has held its Fusion Energy Summer Camp for high school students. 19 participants aged 16 to 19 got to work as researchers and conduct experiments on DTU's small, and Scandinavia's only, NORTH tokamak. From early morning to late evening, from 30 July to 4 August, they followed lectures, practiced problem solving and programming in fusion energy and plasma physics, and participated in experiments, while also having fun and getting a taste of university life on campus. The DTU Physics teams thanks the Novo Nordisk Foundation for its generous support in helping to inspire the young generation to consider an education in science and engineering and be part of the push to develop a sustainable future. --Søren Bang Korsholm, Senior Scientist, and Alexander Simon Thrysøe, Scientist at DTU Physics. Photo: Students are introduced to the NORdic Tokamak device (NORTH) that is enriching the physics and engineering programs at the Technical University of Denmark. Credit: Magnus Møller