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Among the dozens of specially designed tools that will have a role to play in positioning and assembling °ÄÃÅÁùºÏ²Ê¸ßÊÖ's giant machine components, two stand—literally—a head and shoulders above the others. As tall as a seven-storey building, made of hundreds of tonnes of steel, the sector sub-assembly tools will support charges of up to 1,200 tonnes during out-of-pit pre-assembly activities for the °ÄÃÅÁùºÏ²Ê¸ßÊÖ vacuum vessel sectors. With factory assembly nearly finalized, Korea expects to deliver the first tool to the °ÄÃÅÁùºÏ²Ê¸ßÊÖ site in June. At Taekyung Heavy Industries (THI) in Changwon, South Korea, a special assembly area has been created for °ÄÃÅÁùºÏ²Ê¸ßÊÖ's largest custom-designed tool. The base elements are nearly out of sight, installed in a pit dug eight metres into the ground. The towering columns are surrounded by scaffolding. Nearby, a sliding warehouse structure stands ready to protect the work zone in the case of inclement weather. "At 22 metres tall and 860 tonnes, the sector sub-assembly tools are certainly the biggest of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ assembly tools that Korea will procure for °ÄÃÅÁùºÏ²Ê¸ßÊÖ," says Hyung Yeol Yang, from °ÄÃÅÁùºÏ²Ê¸ßÊÖ's Tokamak Assembly Section/Division. "But the challenge is not in their size, even if fabrication does require a huge milling machine, capable of machining components up to 30 metres in length. The challenge is in the function of the tool itself—supporting 440-tonne vacuum vessel sectors while two 310-tonne toroidal field coils are positioned and aligned to millimetre-level assembly tolerances."   Precision hydraulics will drive the tool's lateral wings, which rotate to deliver the toroidal field coils to their installation fixtures on the 40° vacuum vessel sector, suspended in the centre. The different structural elements of the first tool have been manufactured and their in-factory assembly is 70% complete. °ÄÃÅÁùºÏ²Ê¸ßÊÖ's plasma chamber, or vacuum vessel, will be formed from nine wedge-shaped steel sectors that measure over 14 metres in height and weigh 440 tonnes. Each one will be shipped from manufacturing facilities in Europe and Korea on horizontal transport frames. Once delivered to the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Assembly Hall—and following vacuum tests and the installation of magnetic diagnostics—the 40° sectors will be moved to a vertical position, or "upended" in °ÄÃÅÁùºÏ²Ê¸ßÊÖ parlance.   That's where the behemoth sector sub-assembly tools enter the scene. The tools are designed to suspend each sector from the top while vacuum vessel thermal shielding and a pair of toroidal field coils are installed.   The components to be installed are mounted on frames, which are in turn installed on rotating platforms, or "wings," of the sector sub-assembly tool. Hydraulic cylinders located at the base of the tools will urge the rotating platforms forward in the toroidal direction in a "push and clamp" motion. As they approach the suspended vacuum vessel sector, actuators on the rotating platforms will allow the components to be positioned with the highest accuracy—just 1.5 mm for the toroidal field coils—and adjusted to six degrees of freedom*.    "The main structure, rotating frames and actuator system of these hydraulic-powered tools were all tested on a 1:5-scale mockup," reports Hyung Yeol.  "This important qualification step led to improvements in the design, a final design review, and the green light for the start of manufacturing which got off to a start in March 2016."   An area of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Assembly Hall has been specially reinforced to receive the incredible weight of the sector sub-assembly tools (860 tonnes each) and the components they support (1,200 tonnes). Two identical tools will allow vacuum vessel pre-assembly work to proceed more quickly. Today, the assembly of the structure of the first tool has progressed to 70 percent, the actuator system has been delivered for installation, and factory acceptance tests are planned to verify that the tool performs the required movements without jamming or malfunction and that the required alignment can be reached.   If all goes well, the tool will be disassembled and shipped in 54 packages to the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization before the end of June. Re-assembly activities on site and final site acceptance tests—including a load test of 310 tonnes—will be supervised by THI, with work mainly carried out by THI's local contractor CNIM (France).   Fabrication activities will begin on the second sector sub-assembly tool in Korea as soon as the first is shipped.   The Korean Domestic Agency is responsible for the design and fabrication of 43 assembly tools. For the sector sub-assembly tools, its main contractor SFA Engineering Corp has contracted with Taekyung Heavy Industries for the fabrication of all structures, sub-assembly and testing, and on-site installation. Precision hydraulic actuators are supplied by ENERPAC (Spain).   * Six degrees of freedom refers to adjustability along X, Y and Z axes (up and down, side to side, forward and backward) as well as in rotational directions relative to the axes (swivel, tilt, pivot).

°ÄÃÅÁùºÏ²Ê¸ßÊÖ's nuclear safety control electronics have undergone a series of tests in order to demonstrate that they can continue to perform their functions flawlessly even in the case of a seismic event. The mission of the nuclear safety control system (SCS-N) at °ÄÃÅÁùºÏ²Ê¸ßÊÖ is to protect people and the environment against nuclear hazards through instrumentation and control (I&C). SCS-N is charged with detecting incidents or accidents and controlling all the active actions needed to prevent or mitigate those situations.   It is composed of the nuclear central safety system, provided by the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization, and several nuclear plant safety systems supplied by both °ÄÃÅÁùºÏ²Ê¸ßÊÖ and the Domestic Agencies. The contract for the design, qualification and supply of the nuclear central safety system was awarded to a Spanish consortium formed by the companies Empresarios Agrupados and Inabensa.   From 6 to 9 February, seismic tests were carried out on the nuclear safety control system at VIRLAB, a laboratory located in Basque Country, Spain. The objective of the tests was to demonstrate that the nuclear safety I&C systems will execute their functions properly during and after an SL-2 earthquake, which corresponds to the reference seismic level on Cadarache site.   The electronic components had been aged in previous tests to simulate a situation in which the seismic event occurs near or at the end of °ÄÃÅÁùºÏ²Ê¸ßÊÖ's lifetime. In this photo, experts carry out visual inspections. The tests were performed on a set of three test specimens that covered all expected configurations in °ÄÃÅÁùºÏ²Ê¸ßÊÖ nuclear safety control cubicles. Moreover, the Required Response Spectra (RRS) used for the test is an envelope of the seismic spectra of the different locations in °ÄÃÅÁùºÏ²Ê¸ßÊÖ that will house protection-important or safety-important (PIC or SIC) control cubicles. As a result, no additional tests should be necessary to seismically qualify any °ÄÃÅÁùºÏ²Ê¸ßÊÖ nuclear safety control cubicle, a standardization that yields both cost efficiency as well as a reduction in technical risk for the project. An operational mockup of the operator desk was also tested at VIRLAB.   In order to cover the situation in which an earthquake occurs at the end of °ÄÃÅÁùºÏ²Ê¸ßÊÖ's lifetime, after decades of operation, the components that were subjected to the tests had been previously aged by a series of tests whose aim was to speed up the normal ageing processes. During those tests, the electronic components were exposed to aggravated environmental and operation conditions.   The tests were executed on a biaxial shaking table able to produce the movement and acceleration expected at the postulated earthquake. Once the test set-up was ready and all preliminary checks were performed, the test sequence began with an exploration of the critical frequencies of the specimens along each axis. Then the specimens went through five lower level earthquakes both at XZ and YZ directions in order to induce any mechanical ageing in the structures and equipment. Finally, the tests at SL-2 level were executed also along XZ and YZ axes. The attached videos correspond to SL-2 level tests, which lasted about 20 seconds each.   During the tests the control equipment was running a battery of tests that recreate the normal operation of the system, allowing technicians to verify that it was not affected by the "earthquake." These tests were executed before, during, and after subjecting the equipment to the seismic conditions and were complemented by additional diagnostics, including the scan of hard drives, the activation of the protection systems of the cubicle (such as fire extinction), and verification of the redundancy mechanisms of logic solvers.   The results of these seismic tests will be incorporated into the qualification files of the nuclear safety control system, together with the outcome of other tests and different analyses and justifications. All of these important steps will demonstrate the ability of the system to meet requirements within any of the postulated operating conditions.   Click here to view a video of the test.

Japan has the procurement responsibility for 9 of °ÄÃÅÁùºÏ²Ê¸ßÊÖ's 19 superconducting toroidal field winding packs and all 19 of the toroidal field coil cases. In a major production milestone the first winding pack has been completed, after the realization of the winding, heat treatment, radial plate insertion, and impregnation phases. At QST—the National Institutes for Quantum and Radiological Science and Technology which oversee the procurement of all the °ÄÃÅÁùºÏ²Ê¸ßÊÖ components allocated to Japan—teams have been hard at work on the fabrication of the toroidal field coils.   °ÄÃÅÁùºÏ²Ê¸ßÊÖ's powerful D-shaped coils consist of a winding pack enclosed in a thick stainless steel case. The multistep fabrication process of the inner core starts with the winding of seven double pancake modules according to rigorous manufacturing specifications. Conductor unit lengths, for example, must be kept within ± 0.01 percent as they are wound. Next, helium inlets and joints are created and each double pancake module undergoes heat treatment—a process where temperatures of 650 °C for 100 hours (± 5 °C) renders the conductor alloy superconducting.   After heat treatment, radial plates are transferred carefully between conductor layers without causing strain greater than 0.1 percent, to avoid degrading conductor performance. The conductors are then extracted from the radial plate grooves and wrapped in insulating tape before being gently reinserted. At this stage of the process, the double pancake modules are sealed with cover plates by welding and then insulated and impregnated (or "hardened") with resin, a manufacturing step that only tolerates an additional ±1 mm of distortion in planarity over the entire double pancake.   Finally, the seven double pancakes were stacked together to form a winding pack, which was then covered with insulating tape for its ground insulation.   °ÄÃÅÁùºÏ²Ê¸ßÊÖ management is using a number of °ÄÃÅÁùºÏ²Ê¸ßÊÖ Council-approved milestones to track progress of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization and Domestic Agencies against the overall schedule. For Japan, the ground insulation of the winding pack for toroidal field coil #1 is one of these major milestones, which the Japanese teams are proud to have completed ahead of deadline.   The milestone was achieved at the Futami plant of Mitsubishi Heavy Industries Ltd/Mitsubishi Electric Co. Work is also underway, in an identical manufacturing process, at the second Japanese manufacturing line for toroidal field coils—Keihin Product Operations of Toshiba Corp.

The Chinese Domestic Agency is responsible for the procurement of the 14 poloidal field AC/DC converter units that will provide reliable, controlled DC power to the °ÄÃÅÁùºÏ²Ê¸ßÊÖ poloidal field magnetic coils and dummy load for site testing. The series production of poloidal field AC/DC converters is underway in China, following the successful testing of the first prototype unit.   Five poloidal field convertor units and four rectifying transformers will be ready for shipment from China in June. In the picture, are rows of high-power DC reactors for the poloidal field converters, ready for transport.

Two students from Kyoto University (Konishi Laboratory, Institute of Advanced Energy) have set themselves a very ambitious challenge. Taishi Sugiyama and Kaishi Sakane, have given themselves four days to build an °ÄÃÅÁùºÏ²Ê¸ßÊÖ Tokamak ... with a set of 40,000 Lego bricks! The two students, who arrived early this morning at the Marseille airport, participated in the Kyoto University Student Challenge Contest and collected the necessary funds to travel to °ÄÃÅÁùºÏ²Ê¸ßÊÖ.   With their temporary office in the lobby of °ÄÃÅÁùºÏ²Ê¸ßÊÖ Headquarters, the two students are all set to build their third LEGO model of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Tokamak. (Another of their masterpieces was on display at the °ÄÃÅÁùºÏ²Ê¸ßÊÖ stand at last year's Fusion Energy Conference in Kyoto.) Good luck to them and see you in next week's Newsline for the final result!

The representatives of the nuclear institutions of Kazakhstan who visited °ÄÃÅÁùºÏ²Ê¸ßÊÖ last Tuesday stated it simply and clearly: they are very interested in collaborating with °ÄÃÅÁùºÏ²Ê¸ßÊÖ. The largest of the Central Asian republics (5.5 times the size of France), Kazakhstan has immense mineral resources and a strong scientific and technological infrastructure inherited from its Soviet past and expanded since the country's independence in 1991.   Kazakhstan also has a tokamak that happens to share with °ÄÃÅÁùºÏ²Ê¸ßÊÖ the same "godfather": Evgeny Velikhov, the Russian scientist who was instrumental in the launching of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Project in the mid-1980s, and who played a similar role a dozen years later for the Kazakhstan Material Testing (КТМ) tokamak.   °ÄÃÅÁùºÏ²Ê¸ßÊÖ and Kazakhstan go back a long way. Kazakhstani personnel and institutions were involved in the early °ÄÃÅÁùºÏ²Ê¸ßÊÖ design phase during the Soviet period, and as early as 2007 the country expressed an intention to continue its participation in the project.   A tokamak with drawers A collaboration between the Russian Federation and the Republic of Kazakhstan, KTM is a spherical tokamak with a major plasma radius of 0.9 metre, a plasma current of 750 kA and a toroidal magnetic field of 1 Tesla. Inside KTM's "movable" divertor 20 compartments can accommodate material samples that can be loaded and unloaded without loss of vacuum inside the chamber. The heat load deposited on KTM's divertor by the hydrogen-deuterium plasmas is expected to be in the range of 20MW per square metre—similar to what it will be in °ÄÃÅÁùºÏ²Ê¸ßÊÖ. The KTM project was initiated in 1998, construction began in 2003, and a first plasma was produced in 2010 during a trial start-up. The "physical start-up" is scheduled in May-June of this year (before the opening of the world exhibit in Astana) and full-fledged operations with nominal plasma parameters will commence in 2020. Over the past ten years, several delegations from Kazakhstan have visited °ÄÃÅÁùºÏ²Ê¸ßÊÖ. Last Tuesday, the proposal for collaboration was renewed.   In the discussion that took place with °ÄÃÅÁùºÏ²Ê¸ßÊÖ Director-General Bernard Bigot, Erlan Batyrbekov, director of the Kazakhstan Nuclear National Center, offered to establish a legal cooperation framework between °ÄÃÅÁùºÏ²Ê¸ßÊÖ and the institution he heads.( Erlan Batyrbekov was accompanied by Alexandr Vurim, Deputy-Director of the Institute of Atomic Energy, and Vladimir Vityuk, Head of Laboratory). Among other things, this collaboration would enable the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization to access the KTM facility for the testing of plasma-facing materials.   The °ÄÃÅÁùºÏ²Ê¸ßÊÖ Agreement is open to any nation that wishes to contribute to the project. Considering that °ÄÃÅÁùºÏ²Ê¸ßÊÖ now has an overall project schedule through First Plasma (2025) and the start of Deuterium-Tritium fusion power experiments (2035), an increasing number of countries are considering cooperation.   For this reason, °ÄÃÅÁùºÏ²Ê¸ßÊÖ is evaluating the creation of a specific "°ÄÃÅÁùºÏ²Ê¸ßÊÖ Partner" status that would be differentiated from full °ÄÃÅÁùºÏ²Ê¸ßÊÖ Member status. The unanimous consent of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Council is naturally required for any such collaboration or partnership.   On a related note, the World Fair on "Future Energy" will open in June in Kazakhstan's capital, Astana. Kazakhstan's fusion program will be one of the centrepieces of the country's 5,000 m² pavilion; °ÄÃÅÁùºÏ²Ê¸ßÊÖ will also be substantially represented at the Fair as an international exhibition within the French pavilion, featuring mockups, videos, and newly developed animations. The Chinese Domestic Agency will also feature °ÄÃÅÁùºÏ²Ê¸ßÊÖ in a display in the Chinese pavilion, where it will unveil a new °ÄÃÅÁùºÏ²Ê¸ßÊÖ Tokamak model.

Achieving fusion energy is more of a marathon than a sprint. And so is the production of a documentary film on fusion ... although in the beginning of their endeavor, fusion was not even on the list of attractions, says Canadian film producer and two-time Emmy award winner Mila Aung-Thwin.   "About four years ago, I was researching the idea of making a documentary about the future of energy. I'm ashamed to say that at the beginning, fusion wasn't even on my radar. I hadn't heard of °ÄÃÅÁùºÏ²Ê¸ßÊÖ. I got invited to the media and press visit, and came to see what was going on in person. It took me a while to really understand the profound nature of the difficult challenge being undertaken, in terms of both technology and politics. After a while, I realized that I was hooked and had to find a way to tell this amazing story that ended up taking as all around the world."   Now Mila and his co-director and cinematographer Van Royko have completed the final edits of their 90-minute documentary film Let there be light and they have started touring the big film festivals in North America and Europe. This past weekend they showed it in the US at the Big Sky Festival in Montana, and the reception from both the audience and the jury was extremely positive. The film won the "Feature Competition Artistic Vision" award. In the jury's statement it says: "In recognition of the film's artistic merit and educational value, the jury presents Let there be light with an Artistic Vision Award for its cinematic eye, innovative animation, and engaging (passionate) investigation into the future of fusion (clean energy)."   The next big screening is planned at the South By Southwest Film Festival (SXSW) in Austin, Texas, on 10 March. It will be followed by the CPH:DOX festival in Copenhagen, Denmark (also in March), and the Hot Docs Festival in Toronto, Canada—the largest documentary festival in North America—late April. "Let there be light" is a project of EyeSteelFilm.