Conductors

3,000 sensors for detecting the quench

A robust detection system is under development to protect the ITER magnets in case of quenches—those events in a magnet’s lifetime when superconductivity is lost and the conductors return to a resistive state. When cooled to the temperature of 4.5 Kelvin (around minus 269 degrees Celsius), ITER’s magnets will become powerful superconductors. The electrical current surging through a superconductor encounters no electrical resistance, allowing superconducting magnets to carry the high current and produce the strong magnetic fields that are essential for ITER experiments. Superconductivity can be maintained as long as certain thresholds conditions are respected (cryogenic temperatures, current density, magnetic field). Outside of these boundary conditions a magnet will return to its normal resistive state and the high current will produce high heat and voltage. This transition from superconducting to resistive is referred to as a quench. During a quench, temperature, voltage and mechanical stresses increase—not only on the coil itself, but also in the magnet feeders and the magnet structures. A quench that begins in one part of a superconducting coil can propagate, causing other areas to lose their superconductivity. As this phenomenon builds, it is essential to discharge the huge energy accumulated in the magnet to the exterior of the Tokamak Building. _To_57_Tx_Magnet quenches aren’t expected often during the lifetime of ITER, but it is necessary to plan for them. „Quenches aren’t an accident, failure or defect—they are part of the life of a superconducting magnet and the latter must be designed to withstand them,” says Felix Rodriguez-Mateos, the quench detection responsible engineer in the Magnet Division. „It is our job to equip ITER with a de Czytaj dalej...

2nd batch of Russian TF conductors en route to Italy

The superconductors for the ITER magnet system are among the longest-lead production items for the project; the first five Procurement Arrangements concluded by the ITER Organization between late 2007 and mid-2008 concerned the conductors for the toroidal field magnet system. The Russian Domestic Agency is responsible for 20 percent of toroidal field conductor procurement and 14 percent of poloidal field conductor procurement. Production is ongoing according to the schedule of the Procurement Arrangements. On 25 June, the second batch of toroidal field conductor unit lengths started on their way from the premises of the Kurchatov Institute in Moscow to the city of La Spezia, Italy, where the winding of ten toroidal field coils will take place. Demonstrating the attachment of Russian industry to fulfill its contractual obligations on time, two 415-metre production lengths of niobium-tin (Nb3Sn) conductor for toroidal field side double-pancakes were loaded onto trucks at the Institute. This latest shipment follows the delivery of four conductor unit lengths to Europe in October 2012, including a copper dummy and a 100-metre qualification length. Seven similar units lengths have passed all of the tests stipulated in the Procurement Arrangement and meet ITER Organization requirements; they will, in turn, be shipped as well. Czytaj dalej...

Council welcomes progress in construction and manufacturing

The ITER Council met for the twelfth time in its history on June 19-20 in Tokyo, Japan. The meeting brought together senior representatives from the seven ITER Members—China, the European Union, India, Japan, Korea, Russia and the United States—under the chairmanship of Hideyuki Takatsu (Japan). The Council took note of the increasing pace of construction activities on the ITER site and progress in the manufacturing of components and supporting systems, highlighting the fact that major contracts have been placed recently and many leading industries are now involved in ITER construction. During the 12th ITER Council, significant progress was reported in the manufacturing of ITER magnets: over 420 tons of niobium-tin strand (Nb3Sn) for the toroidal field conductors (90 percent of project needs) and 133 tons of niobium-titanium (NbTi) strand for the poloidal field conductors (51 percent of project needs) have been produced to date. The Council reaffirmed the importance of sustained efforts regarding schedule implementation, while recognizing the challenges due to the first-of-a-kind nature of ITER. In this context, the governing body of ITER welcomed improved collaboration between the ITER Organization and the Domestic Agencies as part of the Unique ITER team. Click here to view the photo gallery of the Twelfth ITER Council. Read the Press Releases in English and in French. Czytaj dalej...

China delivers first load to ITER

It’s a long road from the Institute of Plasma Physics (ASIPP) in Hefei, China to the ITER site in southern France: 500 kilometres by route to the port of Shanghai; some 10,000 nautical miles from Shanghai to the port of Marseille-Fos; another hundred kilometres for the last leg of the journey, from Fos to the ITER site. The distance was covered by trucks and the container ship Lyra in 38 days. Three crates that had been loaded at Hefei on 25 April were delivered to the Poloidal Field Coils Winding Building on Monday 2 June, three days ahead of schedule. The crates contained the first batch of ITER items delivered by ITER China to the European Domestic Agency Fusion for Energy (F4E): 737 metres of dummy conductor, in three lengths, to be tested in a mockup of poloidal field coil number five (PF5). The 25-ton load was also the first ITER item to enter the large on-site winding facility. „The conductor will be used to test the whole fabrication process,” explained Neil Mitchell, head of the ITER Magnets Division, as the crates were being unloaded and inspected. „This copper conductor will be wound, tested for tolerance, insulated, impregnated under vacuum and formed into a ‚double pancake’ in the same way the actual superconducting niobium-titanium conductor will be handled by F4E at a later stage. What matters here are the mechanical properties, which are similar in both the copper dummy and the actual superconductor.” An ITER load, even when it’s only a dummy component destined for mockup testing, is not an ordinary load. The transport crates were equipped with several monitoring devices to record movement and accelerations throughout the journey; other systems monitored the pressure inside the conductors, which are filled with pressurized inert gas, to confirm that there Czytaj dalej...

Europe delivers a world class test facility

If we are truly committed to the idea of a sustainable energy mix—with fusion as one of the elements—then we need to invest in facilities that will bring us a step closer to the realization of commercial fusion by helping us test the technology and the components of current and future fusion devices. This is precisely the purpose of the European Dipole project (EDIPO) launched in 2005, whose mission is to manufacture a high field magnet that would ultimately be used to test ITER cable-in-conduit conductors (CICCs) with current up to 100 kA. Switzerland’s Paul Scherrer Institute (PSI), at the Centre of Research in Physics and Plasma (CRPP), is hosting this facility that was built thanks to a collaboration between CRPP, BNG (Babcock Nöll), the European Domestic Agency for ITER (F4E) and the European Commission. The stakes for EDIPO were high from the very start because it had to meet two important conditions. First, it had to offer the fusion community the possibility to test short sample CICCs in a magnetic field up to 12.5 Tesla—an unprecedented level for this type of facility—in order to mimic the ITER environment. Second, the CICCs had to be tested at this level of magnetic field over a length equivalent to about 800 mm, which is roughly two times the high field length of the conductors currently tested in SULTAN. Read more in the Fusion for Energy Newsletter. Czytaj dalej...

First hardware afloat from China

On Thursday 25 April, the morning silence at the Institute of Plasma Physics (ASIPP) in Hefei, China, was broken by the noise of a high powered trailer. Inside the superconductor shop of ASIPP, workers were busy preparing to load the 737 metres of dummy conductor for ITER’s Poloidal Field Coil number five (PF5)—this represents the first delivery from China to the ITER construction site in France.  According to the Procurement Arrangement signed between the Chinese Domestic Agency and the ITER Organization, China will fabricate 64 conductors for ITER’s poloidal field coils, including four dummy conductors for cabling and coil manufacturing process qualification. ASIPP is responsible for all the poloidal field conductor fabrication in China. The fabrication of the PF5 dummy was completed in by ASIPP in 2011.  „This is the very first batch of ITER items to be shipped from China to the ITER site in Cadarache," said Luo Delong, Deputy Director-General of ITER China. Before, conductors for the toroidal field coils had been shipped to Japan and Europe. "This milestone is a further step for the ITER project. According to our schedule, we will now start massive production of conductors this year. Our goal is that all procurement items from China be supplied consistent with the ITER schedule and with ITER quality requirements.” According to the shipment schedule the PF5 dummy conductors, which left Shanghai on 30 April, will arrive at the ITER site on 5 June. Czytaj dalej...

Team work celebrated at last Conductors Meeting

In pre-ITER times, the world production of niobium-tin (Nb3Sn) strands did not exceed 15 tons per year. Discovered in 1954, this intermetallic compound that exhibits a critical temperature of ~18 K and is able to withstand intense magnetic fields was used mainly in high field coils and nuclear magnetic resonance equipment. To match the needs of ITER’s 19 toroidal field coils (18 plus one spare), the world production capacity of Nb3Sn strand had to be ramped up by one order of magnitude. As of today, 400 tons of Nb3Sn have been produced by the industry of the six ITER Domestic Agencies involved in conductor procurement, representing 85 percent of toroidal field coil needs. Nb3Sn conductors will also form the core of the central solenoid, the backbone of the ITER magnet system. Strand production has been launched in Japan for the lower module (CS3L) and conductor lengths will be shipped at a later time to the US where the central solenoid will be manufactured. For ITER’s third major magnet system—the poloidal field coils—because the magnetic field they produce is less intense, they can be manufactured from the metallic alloy niobium-titanium (NbTi), which is cheaper and easier to produce than the brittle Nb3Sn. The Russian-European collaboration that procures NbTi strands for ITER has already produced 80 tons of Strand 1, destined for poloidal field 1 and 6. China, responsible for the procurement of conductors for poloidal field coils 2 to 5, has registered nearly 50 tons of of NbTi Strand 2 into the Conductor Database (this essential tool monitors the strand, cable, jacket and conductor production of each Domestic Agency). China will send its first poloidal field conductor shipment to the ITER site within the next two months. Altogether, conductors for the magnet systems accoun Czytaj dalej...

First Russian TF Conductors shipped to Europe

Russia makes progress with the well-timed procurement of the future facility’s components to the ITER Organization. On 9 October 2012, two qualified unit lengths of Toroidal Field Conductors for the ITER magnetic system were shipped from Kurchatov Institute, in Moscow, to the customs office for their subsequent transportation to Europe. These were the copper dummy and the 100-metre qualification conductor, Russia’s first procurement of the Toroidal Field Coils Conductor. The conductor lengths, manufactured at the Open Joint-Stock Company All-Russian R&D Project-Design and Technological Institute of Cable Industry (OJSC VNIIKP) were delivered from the National Research Centre „Kurchatov Institute”, where they had previously undergone vacuum tests involving special equipment. The next shipment of Toroidal Field Conductors is planned to take place in compliance with the schedule. Click here to view a video of the operation. Czytaj dalej...

Russian TF conductor successfully tested in SULTAN

Having recently celebrated its fifth anniversary, the ITER Project has moved steadily from negotiations to real manufacturing, and from dummy testing to production of the tokamak’s construction elements. One of the first systems to be manufactured in line with the ITER Organization (IO) Integrated Schedule Plan is the superconductor for the ITER magnet system. Russia has demonstrated high stability and reliability during this process, fulfilling all its obligations in time. This has not only been acknowledged by the IO experts, but also by the international superconductor community. The Russian Toroidal Field (TF) conductor with bronze route strands  was tested in the SULTAN facility by Centre de Recherches en Physique des Plasmas- Ecole Polytechnique Fédérale de Lausanne (CRPP-EPFL) in late September — early October 2012. This is the fourth Russian sample to be tested in SULTAN but the first sample containing two sections of conductor made of real production length which will be used to manufacture real TF coils for the machine. The left section of the conductor was cut from side Double Pancake  pre-production conductor (Phase III) while the right section was made from first production (Phase IV) regular Double Pancake. The results obtained with the the TFRF4 (Toroidal Field Russian Federation # 4) sample show very good agreement with results of the two last samples TFRF2 and TFRF3, which demonstrated the relatively good stability of the conductor during electromagnetic cycling, as well as its good durability during the warm-up/cool-down procedure. Testing the TFRF4 sample was a very important milestone which completed the pre-production phase of the TF conductor procurement process. This means we can now proceed to the final production stage. At the same time, it opens the wa Czytaj dalej...

ITER "conductor community" meets in Moscow

The traditional International Conductor meeting was held in Moscow on 10-13 September, 2012. The regular meeting was attended by representatives from the ITER Organization, experts from the ITER Domestic Agencies of Europe, China, Japan, Republic of Korea, Russia and USA, as well as specialists from the DAs’ suppliers. Such meetings are particularly important since the ITER magnetic system, with conductors forming its core, is one of the ITER tokamak’s key elements. The manufactured conductors, which are designed to withstand super high current in continuous mode, have to meet the IO’s strict requirements. At the moment, 10 out of the 11 conductor Procurement Agreements, are either well into the production phase or are completing the qualification/pre-production phase. This is particularly true for the Toroidal Field conductors, where 75 percent of the required Nb3Sn strands and one third of the cable-in-conduit conductor unit lengths have been completed. Also, a technical solution has been found for the Central Solenoid conductors that are being implemented by the ITER Japanese partner. „This is a clear indication  that the ITER project is moving ahead and is able to keep schedule”, says the meeting’s Chair Arnaud Devred, ITER Superconductor Systems and Auxiliaries Section Leader. In Devred’s opinion, „in spite of the difficulties of coordinating work with about 30 suppliers and six DAs around the world, the ITER conductor community has always tried to work in a cooperative and synergetic manner, and the conductor meetings have always been a great opportunity for sharing experience and tackling difficult interface issues. The conductor meeting is also an opportunity to showcase the work done in the Russian Federation and for the DAs involved in coils procur Czytaj dalej...

Conductors for six out of 18 Toroidal Field coils manufactured

The production of superconducting cables for ITER’s large and powerful Toroidal Field (TF) coils is making remarkable progress: as of today, 330 tons of strands made out of Nb_SUBSCRIPT_3_/SUBSCRIPT_Sn, a special alloy made of niobium and tin, have been produced in factories in China, Europe, Japan, Korea, Russia and the United States. In the pre-ITER world, global production was 15 tons a year. „The current production status represents 75% of the total required TF strands”, reports Arnaud Devred, Section Leader for ITER’s Superconducting Systems. "Out of these strands, conductors for six out of the machine’s 18 TF coils have been produced." The 18 TF coils will produce a magnetic field around the ITER torus helping to confine and control the plasma inside. The coils are designed to achieve operation at magnetic fields up to 13 Tesla. They are made of cable-in-conduit superconductors, in which a bundle of superconducting strands is cabled together and contained in a structural jacket. Unit lengths of theses cables — measuring 760 metres or 415 metres depending on their position within the coil – are then spooled into a D-shaped double spiral called a „double pancake” giving the structure the characteristic shape of ITER’s TF coils. As of today, a total of 30 760-m Unit Lengths and 13 415-m Unit Lengths have been manufactured by the procuring agencies in Japan, Korea, Russia and Europe which adds up to the material required for six of the 18 TF coils. „Quality tests”, says Devred, „are currently underway to confirm that these unit lengths can be accepted for coil winding”. Nb_SUBSCRIPT_3_/SUBSCRIPT_Sn Czytaj dalej...

Where conductors are born

Manufacturing the toroidal field conductors for the ITER magnet system is a sophisticated, multistage process. Early this year, specialists at the All-Russian Cable Scientific Research and Development Institute (VNIIKP) in Podolsk, Russia twisted semiconductor strands into a 760-metre niobium-tin (Nb3Sn) cable—the second product of this kind manufactured in Russia.  At the end of February, at the High Energy Physics Institute in Protvino, this cable was pulled through a stainless steel jacket that had been assembled on site. The process involved the most advanced Russian technology and knowhow. The jacket itself—reaching nearly a kilometre in length and composed of more than 70 tubes welded together by gas tungsten-arc welding technology—was exposed to triple testing of the weld seams’ quality and reliability. During the next stage in the process, the jacketed cable, called a conductor, was compacted and spooled into a solenoid measuring four metres in diameter. Following vacuum and hydraulic tests at the Kurchatov Institute in Moscow, the conductor will be shipped to Europe. Follow this link to a 10-minute video in English that will bring you inside the Russian factories involved with toroidal field conductor manufacturing for ITER. Click here to see the video in Russian. Czytaj dalej...

An eagerly anticipated dummy

After driving through the night, the oversize truck pulls up in the early May dawn at the ASG facilities in La Spezia, Italy. The special delivery, a wooden square box with 5-metre dimensions, contains a large spool around which the eagerly anticipated dummy of a 760 m long copper conductor is wound. The dummy is a mockup of the ITER conductors. These conductors will each be used in the toroidal field coils to carry 68,000 amps of electrical current in order to produce the magnetic field which confines and holds the plasma in place. In total, 19 superconducting conductor lengths (each measuring 760 m) and 8 conductors (each measuring 415 m) will be produced. Although the final components will consist of superconducting materials, the dummy is made only of copper strands which have been plaited together (cabled) and inserted into a jacket in order to form a round conductor with a diameter of 44 mm. Nonetheless, the dummy package weighs an impressive 13 tons. Because of its large dimensions, it is only transportable during certain hours of the night after other traffic has been cleared. The dummy was manufactured for the European Domestic Agency F4E by ICAS, an Italian consortium consisting of the Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), Criotec, and Tratos Cavi. The next steps of the process will be undertaken by ASG, part of the Iberdrola consortium (which includes Iberdrola and Elytt), F4E’s toroidal field coil supplier and the company to which the dummy was delivered. The copper dummy length will be used for the commissioning of the toroidal field coil winding line. In recent months, two additional toroidal field lengths made from superconducting strand were manufactured, thus completing the qualifi Czytaj dalej...

A new database tool for magnet production

One of the greatest challenges to monitoring the production of the large and complex components at the heart of the ITER magnet system is the quick and efficient exchange of quality assurance/quality control (QA/QC) documents and data—important information that needs to be reviewed during the manufacturing process and cleared for acceptance by the responsible Domestic Agency and the ITER Organization. Following the successful implementation of the Conductor Database tool that tracked production data for the ITER conductors at six Domestic Agencies and their suppliers right through to final acceptance tests, it was decided to develop and implement a Magnet Manufacturing Database (MMD) on the same model. The Magnet Manufacturing Database will be the main tool for monitoring the QA/QC processes of the Procurement Arrangements for magnet coils, magnet structures and magnet feeders. This web-based application, integrated into ITER’s collaborative platform ICP, provides data and process integration with unified access and workflow. For the manufacturers, it offers an inventory control system with the possibility of integrating test result data and acceptance criteria functionalities, and of automatically generating barcodes and lot/serial numbers to facilitate tracking. For the ITER Organization, the workflow management system included in the database matches the control points defined in each Procurement Arrangement and the manufacturing processes defined in the Manufacturing Inspection Plan. References to ITER documents are included for procedures, instructions, and specifications … allowing the ITER Organization to identify and manage critical operations such as welding. The Magnet Manufacturing Database can manage any kind of complex manufacturing process chain, regardless of pro Czytaj dalej...