Subscribe options

Select your newsletters:


Please enter your email address:

@

News & Media

Latest ITER Newsline

  • The physics behind the transition to H-mode

    H‐mode—or thesudden improvement of plasma confinement in the magnetic field of tokamaksby approximatelya factor of two—is thehigh confinement regime that all mo [...]

    Read more

  • In search of the green plasma

    Sébastien König's core competence is in planning and scheduling; his passion is in understanding the workings of the Universe. In his previous life, before join [...]

    Read more

  • An outing into the future

    Open Doors days occur with scientific regularity at ITER (spring and autumn) and yet—due to the rapid evolution of work on site—each event offers something new. [...]

    Read more

  • Fusion "grandfather" tells family story

    Grandfathers like to tell stories. And Robert Aymar, the 'grandfather' of the French fusion community, is no exception. 'Being so old,' he quipped at last week' [...]

    Read more

  • An AC/DC adapter ... ITER size

    Like flashlight and smartphones, the ITER magnets—all 10,000 tonnes of them—will run on direct current (DC). And like flashlight and smartphones they will need [...]

    Read more

Of Interest

See archived articles

Cryostat welding begins

-R.A.

A few weeks ago, the six tier 1 segments of the cryostat base were positioned on an assembly frame in the Cryostat Workshop and readied for welding operations. Using optical metrology, the 50-tonne elements were carefully aligned like so many slices of a giant steel pie, each separated from the next by a 4 millimetre gap to be filled by welding.

The welding of such a giant component is an impressive sight indeed. Welders, crouching or lying, look positively small on the polished steel surfaces of the segments. (Click to view larger version...)
The welding of such a giant component is an impressive sight indeed. Welders, crouching or lying, look positively small on the polished steel surfaces of the segments.
Before the welders could step on the circular stage, however, one last preparatory step needed to be performed: the "coconut ceremony" which, in the Indian tradition, accompanies important occasions and new starts such as a wedding, a journey or ... a construction project.

On Thursday 8 September, when the last of the coconuts had been broken and shared between all participants, the first welding operations for the ITER cryostat could get off to a start.

Welders work in perfectly coordinated pairs—one operating from on top of the 50-millimetre-thick steel plate and the other, invisible, from underneath.<br /><br /> (Click to view larger version...)
Welders work in perfectly coordinated pairs—one operating from on top of the 50-millimetre-thick steel plate and the other, invisible, from underneath.

The welding of such a giant component is an impressive sight indeed. Welders, crouching or lying, look positively small on the polished steel surfaces of the segments. With protective masks that are illuminated by the intense blue light of the electric arc, they work in perfectly coordinated pairs—one operating from on top of the 50-millimetre-thick steel plate and the other, invisible, from underneath.

Throwing a bridge between the high-tech world of ITER and the Indian tradition of times immemorial, participants broke coconuts to call upon the welding operations the blessing of the elephant-headed Ganesha, the ''remover of obstacles.'' (Click to view larger version...)
Throwing a bridge between the high-tech world of ITER and the Indian tradition of times immemorial, participants broke coconuts to call upon the welding operations the blessing of the elephant-headed Ganesha, the ''remover of obstacles.''
As each segment is made of two steel plates joined by a series of ribs, the same welding operations will be performed on both the upper and lower plates.

When all welding operations are completed on the six tier 1 segments, the pedestal ring (which supports the machine) and the "rim" that runs around the base will be added, thus completing, less than a year and a half from now, the single largest load of the machine assembly—the cryostat base.


return to the latest published articles