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ITER NEWSLINE 278
Drain tank fabrication for ITER's tokamak cooling water system is progressing steadily under the leadership of US ITER, which is managed by Oak Ridge National Laboratory for the US Department of Energy. The drain tanks will be among the first major hardware items shipped to the ITER site in France. The US production timing will accommodate the installation sequence for the ITER fusion facility.
Joseph Oat Corporation, a sub-contractor to AREVA Federal Services based in Camden, New Jersey, has begun fabrication activities for four 10-metre-tall, 78 metric ton drain tanks and one 5-metre-tall, 46 metric ton drain tank. Another industry partner, ODOM Industries in Milford, Ohio, is fabricating the ten tank heads as a sub-contractor to the Joseph Oat Corporation.
ODOM will ship each tank head as it is fabricated, and will complete delivery to Joseph Oat Corporation by the end of 2013. Joseph Oat, which specializes in industrial fabrication of pressure vessels and heat exchange technologies, expects to stagger completion of drain tanks throughout the summer and fall of 2014.
"Because the tanks are so large, the ITER Organization will install the tanks one at a time and do so before the neighbouring building is constructed," Chris Beatty, US ITER tokamak cooling water systems engineer, said.
Beatty noted that the Hot Cell building will permanently block access to the drain tanks in the Tokamak Complex once the ITER facility is complete. The tanks, which are built to last 40 years, are expected to perform beyond the duration of the ITER project.
The tokamak cooling water system includes over 20 miles of piping in an intricate network that wraps around the ITER Tokamak. The primary cooling water system is responsible for transferring heat from Tokamak hardware to the secondary cooling system. The tokamak cooling water system also supports operations such as the baking of in-vessel components, chemical control of water provided to client systems, and draining and drying for maintenance.
"There are many ways to cool a reactor, but ITER uses water to cool the internal parts," said Juan Ferrada, US ITER tokamak cooling water senior systems engineer and technical project officer.
When the water isn't being used for operations, such as cooling the system through the network of pipes, it can be stored in the four large drain tanks that hold up to 63,000 gallons of water each. Two 78-tonne tanks are reserved for normal maintenance and operations. During maintenance, the smaller, 46-tonne tank will store coolant for the neutral beam injector that pelts high-energy atoms into the Tokamak to heat the plasma.
The other two 78-tonne tanks, known as the safety drain tanks, are primarily used for storage in case water should leak into the vacuum vessel. Because fusion reactions use tritium and the plasma-facing wall is made of beryllium, the safety tanks are designed to hold water with radioactive particles such as dust, tritium and activated corrosion products.
The pressurized, stainless steel drain tanks must meet French regulations, giving these US fabricators the opportunity to gain experience implementing French regulations for nuclear pressure equipment.
"Compliance with French nuclear pressure equipment regulations is new to most manufacturers in the US," says Glen Cowart, US ITER quality assurance specialist. "In addition, tank fabrication must meet the ITER Organization's requirements as well as engineering and quality criteria established by AREVA Federal Services and US ITER."
"We have to make sure our design criteria meet the French regulations so the tanks can be used for ITER nuclear operations in France," Beatty explains.
Following approved designs, the tanks are being fabricated out of stainless steel plates. Typical plates are 2.7 metres wide and nearly 10 metres long, with each plate weighing over 8.5 tonnes. The design requires that each tank have two hemispherical heads—comprised of a curved top cap and a base, fabricated from six segments (called petals) that are welded together. Joseph Oat has begun bevelling and welding the plates, and rolling them into a cylindrical shape. The caps and base will then be welded to the cylindrical body to form the approximately 6-metre-diameter tanks.
Although the drain tanks are simple equipment from an engineering standpoint when compared to many parts of ITER, their sheer size and weight, in addition to being the first set of US ITER-provided equipment fabricated under the French nuclear regulatory framework, make the fabrication and delivery process extremely demanding.
"Even moving the plates is time consuming," Beatty said. "It takes about an hour to move them from the bevelling machine to where they will be welded. Once they're welded, the plates are even larger, so it can take half a day just to flip them over."
Once the tanks are completed, approved for nuclear pressure safety and delivered to the ITER site in France, they will pose one more challenge: Positioning the heavy tanks inside the Tokamak Complex. To meet this challenge, plans are already in place for using specialized air pads to manoeuvre the tanks to their permanent home in the ITER facility.
See the original article on the US ITER website.
The Korean Domestic Agency signed an important contract in July for the fabrication of neutral beam port in-wall shielding with Korean supplier Hyundai Heavy Industries Co., LTD (HHI). Through this contract, installation of the in-wall shielding into the port stub extensions will begin in mid-2015 with fabrication completed by early 2016. Hyundai Heavy Industries is also manufacturing two sectors of ITER vacuum vessel as contractor to the Korean Domestic Agency, as well as seventeen equatorial ports and the nine lower ports
The vacuum vessel's neutral beam ports are composed of a connecting duct, port extension, and port stub extension. The spaces between the inner and outer shells of the port extension and port stub extension are filled with preassembled blocks called in-wall shielding. The main purpose of in-wall shielding is to provide neutron shielding for the superconducting magnets, the thermal shield and the cryostat.
In order to provide effective neutron shielding capability with the cooling water, 40-millimetre-thick flat plates (steel type 304B4) are used in almost all areas of the volume between port shells.
In-wall shielding is composed of shield plates, upper/lower brackets and bolt/nut/washers. Pre-assembled 368 in-wall shielding blocks will be assembled into the neutral beam port extension and port stub extension during port fabrication, while 160 field joint in-wall shielding blocks will be assembled after field joint welding on the ITER site. The total net weight of all neutral beam in-wall shielding approximates 100 tonnes.
Ki-jung Jung, Director-General of the Korean Domestic Agency, commented during the signature: "ITER Korea takes very seriously the demands of the vacuum vessel schedule and quality requirements by ITER."
It's that time of year again. With the last days of August upon us and a busy September just around the corner, it's a good time to stop and take measure of the evolution of the ITER Organization. The 2012 ITER Organization Annual Report, just released, recounts one year in the life of the ITER Project—the highlights in every technical department, the organizational challenges faced (and the solutions set into motion), and milestones in construction and manufacturing.
In 2012, the ITER project entered the third year of its Construction Phase. The ground support structure and seismic isolation system for the future Tokamak Complex was completed, work began on the site of the Assembly Building, the ITER site was connected to the French electrical grid, and part of the ITER team—approximately 500 people—moved into the completed Headquarters building.
The year 2012 was also witness to the accomplishment of a major licensing milestone when, in November, ITER became the world's first fusion device to obtain nuclear licensing.
The project made a definitive shift in 2012 from design work and process qualification to concrete manufacturing and production. To match this important evolution, the 2012 Annual Report introduces a new feature—the last pages of the report (pp. 40-48) are now reserved for reports from the Domestic Agencies. How is the procurement of ITER systems divided among the Domestic Agencies? Where are activities for ITER taking place in each Member? What percentage of work has been signed over by the ITER Organization in the form of Procurement Arrangements? And, finally: What major manufacturing milestones were accomplished in 2012?
The ITER Organization 2012 Annual Report and 2012 Financial Statements are available online at ITER's Publication Centre.
ITER owes much to a few. At different moments in the history (and prehistory!) of the project, a handful of individuals made moves that were to prove decisive. Among this band of godfathers—whether scientists, politicians, diplomats or senior bureaucrats—Umberto Finzi stands prominently.
Finzi, who retired from the European Commission in 2004 but continued to advise the Director General of Research until the conclusion of the ITER negotiations in 2006, belongs to the generation who embraced fusion research in the early 1960s at a time when plasma physics was still in its infancy.
A physicist turned bureaucrat—he was called to Brussels to take care of setting up JET in 1978 and was appointed Head of the European Fusion Programme in 1996—Finzi played a key role in the negotiations that led to building ITER in Europe. An ITER godfather in his own right, he nevertheless insists on the "collective action" that, under four successive European presidencies, led to this decision.
Time has passed. The "paper project" whose roots go back to the late 1970s, years before the seminal 1985 Reagan-Gorbatchev summit in Geneva, is now a reality, as tangible as it is spectacular. When he toured the ITER worksite on 30 July, Umberto Finzi took the full measure of the progress accomplished since his last visit in 2006, when all there was to see was a hilly, wooded landscape and a high pole marking the future location of the Tokamak.
"During most of my professional life," he said, "ITER was a dream. You can imagine my emotion seeing these tons of steel and concrete. This reminds me of the famous message by Hergé¹ to Neil Armstrong: "By believing in his dreams, man turns them into reality."
"ITER is a difficult venture," he added, "and difficult ventures requiretime and patience. The effort is not only scientific or technological. It lies also, and maybe essentially, in the planning and coordination."
ITER, with 35 participating nations, could have been a Tower of Babel. "On the contrary," says Finzi, "it is the exact opposite of a Tower of Babel, a beautiful demonstration of worldwide understanding. No project has ever associated so many different nations. To me, this is the most important aspect of ITER, a historical dimension that reaches beyond the project's scientific and technological objectives."
(1) Hergé (1907-1983) was a Belgian cartoonist, creator of the world-famous characters Tintin and Snowy. Between 1930 and 1986, Hergé published 23 albums of The Adventures of Tintin, selling a total of 200 million copies in 70 languages. Fifteen years before Neil Armstrong, Tintin, Snowy and other recurrent characters in the series walked on the Moon in the 1954 album "Explorers on the Moon."