Subscribe options

Select your newsletters:


Please enter your email address:

@

News & Media

Latest ITER Newsline

  • A world in itself

    From a height of some 50 metres, you have the entire ITER worksite at your feet. The long rectangle of the Diagnostics Building stands out in the centre, with [...]

    Read more

  • US completes toroidal field deliveries for ITER

    The US Domestic Agency achieved a major milestone in February by completing the delivery of all US-supplied toroidal field conductor to the European toroidal fi [...]

    Read more

  • Thin diagnostic coils to be fitted into giant magnets

    Last week was marked by the first delivery of diagnostic components—Continuous External Rogowski (CER) coils—from the European Domestic Agency to the ITER Organ [...]

    Read more

  • Addressing the challenge of plasma disruptions

    Plasma disruptions are fast events in tokamak plasmas that lead to the complete loss of the thermal and magnetic energy stored in the plasma. The plasma control [...]

    Read more

  • Blending (almost) seamlessly into the landscape

    Located in the foothills of the French Pre-Alps, the ITER installation blends almost seamlessly into the landscape. The architects' choice ofmirror-like steel c [...]

    Read more

Of Interest

See archived articles

A tall accomplishment

-Krista Dulon

12 metres high: the ITER Korea team stands before the full-scale mock-up of the 10° VVTS inboard section, completed in 2010. (Click to view larger version...)
12 metres high: the ITER Korea team stands before the full-scale mock-up of the 10° VVTS inboard section, completed in 2010.
Some of the manufacturing processes tested during fabrication of the mock-up. (Click to view larger version...)
Some of the manufacturing processes tested during fabrication of the mock-up.
The Korean Domestic Agency, in cooperation with Daebong Acrotec, has completed a full-scale mock-up of a 10° inboard section of the ITER Thermal Shield, and tested the main procedures of fabrication including cutting, bending, forming, buffing, welding, and machining.

"We are pleased to report that all the processes for thermal shield manufacture were demonstrated, with the exception of last-stage silver coating," said Wooho Chung, Technical Responsible Officer. "The fabrication of the mock-up allowed us to validate the design and manufacturing process for the ITER Thermal Shield."

Inserted between toroidal field magnets and the vacuum vessel, the ITER Thermal Shield (TS) system minimizes the thermal radiation to the superconducting magnets. Made of stainless steel panels coated with low-emissivity silver, connecting joints (flanges) and cooling pipes welded to the panels, the TS is operated within the range of 80-100 K during plasma operation. The TS surface area covers 10,000 square metres; once assembled, it will stand 25 metres at its highest point.

Two TS segments — the outboard segment and the inboard segment - will be manufactured separately by Korea and then assembled to form a full torus shape. As an open structure, each segment is susceptible to distortion caused by cutting, machining or welding. "It is very important to validate all design and requirement parameters before beginning fabrication," stresses Chung. "The tolerance requirements for the joints in particular are very strict."

During the fabrication of the 10° inboard section mock-up, each step of the manufacturing process was validated. Panel thickness and distortion were measured after the bending and forming stages; all welds were successfully verified; and the machining processes were tested. One important finding from the mock-up fabrication was that the inboard segment is more flexible than expected, making the handling jig essential during fabrication. However, the structural flexibility of individual segment is beneficial for the assembly of the 40° sector.

"We now plan to make another mock-up - the TS outboard 10° section - which will be assembled with the inboard section," says Chung. "These mock-ups will be used in the test of silver electroplating processes."

The detailed design of the ITER Thermal Shield will be reviewed in 2011. The beginning of fabrication is expected in early 2012.


return to the latest published articles