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You're currently reading the news digest published from 24 April 2017 to 1 May 2017.
Featured (6)
Of interest (1)
Press (5)
Featured
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Going to the World's Fair: ITER in Kazakhstan

On Saturday 10 June, the World's Fair will open for the first time in the central Asian Republic of Kazakhstan ... and ITER will be there. The World's Fair has a long tradition of drawing attention to breakthrough innovative technologies. It was first held at Hyde Park in London in 1851, where a spectacular iron-and-glass construction—the Crystal Palace—captured public attention. World's Fairs were also the first public stage for Alexander Graham Bell's telephone (Philadelphia, US: 1876); the diesel engine (Paris, France: 1900), IMAX cinema (Osaka, Japan: 1970), and the first touch screen (Knoxville, Tennessee, US: 1982), to name only a few of the many great inventions that premiered at these popular international gatherings.   With a focus on "Future Energy," this year's Fair—EXPO 2017 in Astana, Kazakhstan—was a perfect fit for the ITER Project. In keeping with France's role as Host to the project, the ITER Organization was invited to participate as an international presence within the French Pavilion. Over 100 square metres will be allocated to showcasing this unique multinational quest for a clean, safe and virtually unlimited source of energy for humankind.   The ITER Organization has designed a unique exhibition to present the science and technology of fusion, the international collaboration behind the project, and finally the construction status of the world's largest and most complex undertaking in the history of science. Part of the ITER cryostat is reproduced at full scale in Astana, with openings that show different aspects of the ITER story on large-screen video. And there will be more on offer at EXPO 2017 for those interested in fusion science and technology:   * The ITER Director-General, Bernard Bigot, will be at the opening of the ITER exhibit on 10 June * Also on 10 June, the Kazakh Tokamak for Material studies (KTM) will celebrate the start of a new campaign with a live feed to the National Nuclear Centre in Kurchatov, the KTM home laboratory* In the Chinese Pavilion, our partners have created an impressive interactive model of the ITER machine and will also be showcasing Chinese contributions to ITER * On 19-20 June, the World Scientific and Engineering Congress (WSEC) will be looking at "Sources and technologies of future energy"* On 24-25 July, the European Union will be hosting EU Energy Days on the theme of "General access to sustainable energy"   EXPO 2017 will be open from 10 June through 10 September 2017.   For more information on EXPO 2017, please click here.
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Countdown

Like a rocket aiming for the stars, crane C1 rises from the deep well of the Tokamak Pit.   There are many parallels to be drawn between the quest for fusion and space exploration. Both challenges are among the most ambitious mankind has ever attempted; both herald a new age in the history of civilization.   Take in this spectacular view while you can—soon, a temporary steel cap will be installed that will shut off the lowest level from the rest of the "well." This cap will protect workers below while work proceeds on the upper levels of the bioshield.   Then, once the building has risen all around and the Tokamak "Pit" is protected from the elements, this space will be progressively filled in with the components of the machine.   In late 2024, a one-year integrated commissioning period is planned to test the systems together. Countdown will then start to First Plasma, scheduled in December 2025.
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Make room for a massive component

When assembling parts for a component as massive as the ITER cryostat, space soon becomes scarce—even in a 110-metre long, 50 metre-wide workshop. This view from up high tells it all. The fabrication and transport frame for the cryostat base and the base section itself (tier one, 30 metres in diameter) occupy almost one-third of the 5,500 square metres available; the remaining space is taken up by the pedestal ring and shell sectors for cryostat base, stored under blue tarps, and the first segments of the lower cylinder delivered recently (in red).   Currently, technicians in the Cryostat Workshop are finalizing tier one of the cryostat base and installing a second assembly frame for the lower cylinder.   Additional welding is being performed on the 18 bottom plates that will eventually "close" the base section. Each of the six "pie-shaped" segments of the base has three bottom plates. The six 50-tonne segments that form the main part of the base section are now welded; the welds have been carefully checked by radiography and helium leak testing techniques.   There is, however, additional welding to be performed on the 18 bottom plates (3 per segment) that will eventually "close" the base section. The operation, shown in the photo above, should be completed in the coming weeks.   Once assembled, the lower cylinder (tiers one and two) will be welded onto the base section. Both base section and lower cylinder should be finalized by the second quarter of 2018. At the far end of the workshop, work has begun on the assembly of the fabrication and transport frame for the lower cylinder. Once this is finalized, the first lower cylinder segments will be positioned on the frame and welded; a "second storey" will be added once the tier-two segments are delivered in September.   Both the base section and the lower cylinder should be finalized by the second quarter of 2018.   While the base section will remain inside the Cryostat Workshop, the lower cylinder will be stored in a dedicated area adjacent to the building. The 490-tonne component will be encased in an airtight cocoon with a regulated atmosphere.   The space freed in the Cryostat Workshop will then be devoted to the assembly and welding of the upper cylinder.   The elements of ITER's giant "thermos" will be installed according to the assembly sequences planned for the machine. The cryostat base section—at 1,250 tonnes—will be the single largest lift of the machine assembly phase.
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Central solenoid feels the heat

The first of six independent magnets for ITER's central solenoid has successfully passed the heat treatment phase, which ultimately creates the solenoid's superconducting material. This milestone was reached in April at General Atomics (US), after the 110-tonne module spent just over ten days at 570 °C and another four at 650 °C. Heat treatment is the fabrication step during which the niobium and tin are reacted together to form the superconducting Nb3Sn alloy. The furnace—which is 12 metres tall when opened, with a diameter of 5.5 metres—holds one module at a time.   Temperatures are increased very progressively, maintained, then decreased progressively in a process that maintains the uniform "cooking" of the module.   "The heat treatment is what ultimately creates the solenoid's superconducting material, and completion of this process demonstrates that we are continuing to make good, consistent progress on this project," said John Smith, program manager for General Atomics.   The central solenoid magnet is formed from six individual coil modules stacked vertically within a "cage" of supporting structures.   At a facility in Poway, California, the US contractor General Atomics is currently overseeing fabrication activity at several points along its manufacturing line. While the first production module passes from the heat treatment station to the turn insulation station, teams are already joining the conductor sections of the second module. Finally the qualification coil—used to validate all processes and tooling in advance of series production—has entered the final test station.   See the full press release from General Atomics.
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Correction coils: case manufacturing to start

New progress has been made in the effort to qualify key manufacturing steps for correction coils—the 18 superconducting coils that will have a role to play in the overall magnetic geometry produced by ITER's different magnet systems. At ASIPP in Hefei, China, a recent manufacturing readiness review has confirmed that the fabrication of the coil cases can begin. It was the third of four reviews planned to review the full scope of correction coil manufacturing—a manufacturing readiness review held from 22 to 23 March to confirm that the casing of the bottom correction coils had successfully passed all qualification steps.   Specifically, the review panel was asked to assess a qualification casing section in the following areas: production of base material, assembly, welding, heat treatment, and finally dimensional control. Following the successful outcome of the review, work can now start to fabricate the production casing segments. All material has been ordered from the Chinese supplier TISCO.   Eighteen steel cases will be fabricated for the correction coils from 120 tonnes of casing material. Case segments will be produced, welded together and finally heat treated—a procedure that allows the welds to "relax" and release stress, and produces a structure that remains stable over time. After the coil winding pack is inserted, the top lid of the case will be positioned and closure welded.   Shown in magenta: six top and six side correction coils. The bottom correction coils (not visible) are in production now at ASIPP in China. The coil winding process had already been validated through earlier manufacturing readiness reviews and the first bottom coil production winding pack has now progressed to the vacuum impregnation stage. Later this year a review is planned to assess the final qualification steps—the insertion of the dummy winding pack into a prototype case and laser closure welding.   "It was highly useful for the review panel to be on site at ASIPP in Hefei to see the production facility and all prototype realizations, as well as the first production winding pack and casing. Preparations ahead of the meeting and constructive discussions with ASIPP over the two days also contributed to the quality of the review," says Fabrice Simon, from ITER's Magnet Division. "Correction coil manufacturing is progressing on schedule and the first six coils—the bottom correction coils—are expected on site in early 2019."
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And now, it's for keeps!

At first view, nothing distinguishes the current operations in the Poloidal Field Coils Winding Facility from those that got underway last November: steel-jacketed conductor is being unspooled, straightened, cleaned, bent to the correct angle, and wrapped with layers of insulating tape ... technicians in white lab coats are carefully performing dimensional checks ... and there is the same machine hum and flash of orange lights. Although invisible to the eye, the difference is nonetheless essential—this time it is not "dummy" conductor on the winding table but the actual niobium-titanium (Nb-Ti) superconductor for poloidal field coil #5 (PF5). Measuring 17 metres in diameter, PF5 will be the second ring coil to take its place in the Tokamak assembly sequence, just above the smaller poloidal field coil #6. The difference lies in the heart of the steel-jacketed component. In the dummy conductor, the strands were one hundred percent copper. This less-expensive material—which respected the actual dimensions of the true conductor—was a good choice for qualifying the production line; contractors used it to first produce a semi-winding (four turns) and then a full two-layer dummy double pancake. In the actual conductor, the strands consist of a mix of copper and of the superconducting alloy niobium-titanium. Four poloidal field coils (out of the six needed for the machine), will be manufactured by Europe in the Poloidal Field Coils Winding Facility. With diameters of 17 to 24 metres and weights ranging from 200 to 400 tonnes, these impressive components will require approximately 18 months each to manufacture. Two smaller ring coils, with diameters of approximately 8 metres, are in production now in Russia and China.See a recent report from the European Domestic Agency on fabrication activities for poloidal field coils #5 and #6 here.
Of interest

Useful downtime at Wendelstein 7-X

https://www.iter.org/of-interest?id=704
Following an initial run at the Wendelstein 7-X stellarator that lasted from December 2015 to March 2016, a shutdown phase ensued to equip the machine for an operational campaign with longer discharges and higher heating power. As part of tasks to prepare for the next phase, programmed to start this summer, technicians have installed or adapted 8,000 graphite tiles on the inner wall of the plasma vessel, replaced the limiter with a test divertor, and installed cooling structures such as pipes and shields. Read about the complexity of these shutdown activities in the latest "Wendelstein 7-X Newsletter." Image: courtesy of IPP Greifswald
Press

A Strategic Plan for U.S. Burning Plasma Research

http://sites.nationalacademies.org/BPA/BPA_177107

ITER: The world's largest fusion experiment (video)

http://video.cnbc.com/gallery/?video=3000612616&play=1

ITER: Demonstrating the feasibility of fusion (video)

http://video.cnbc.com/gallery/?video=3000612617&play=1

Behind the scenes at ITER (video)

http://video.cnbc.com/gallery/?video=3000612619&play=1

Completing the "world's largest fusion experiment" ITER (video)

http://video.cnbc.com/gallery/?video=3000612618&play=1