Subscribe options

Select your newsletters:

Please enter your email address:

@

Your email address will only be used for the purpose of sending you the ITER Organization publication(s) that you have requested. ITER Organization will not transfer your email address or other personal data to any other party or use it for commercial purposes.

If you change your mind, you can easily unsubscribe by clicking the unsubscribe option at the bottom of an email you've received from ITER Organization.

For more information, see our Privacy policy.

News & Media

Latest ITER Newsline

  • European Physical Society | ITER presents its new plans

    The new ITER baseline and its associated research plan were presented last week at the 50th annual conference of the European Physical Society Plasma Physics Di [...]

    Read more

  • Image of the week | The platform's quasi-final appearance

    Since preparation work began in 2007 on the stretch of land that was to host the 42-hectare ITER platform, regular photographic surveys have been organized to d [...]

    Read more

  • Cryopumps | Preparing for the cold tests

    Before being delivered to ITER, the torus and cryostat cryopumps are submitted to a  comprehensive series of factory acceptance tests. This is not sufficie [...]

    Read more

  • Fusion technologies | Closing a fusion schism

    Historically, inertial confinement and magnetic confinement approaches to fusion have been parallel, separate processes. The ITER Private Sector Fusion Workshop [...]

    Read more

  • Toroidal field coil celebration | "A good day for the world"

    A little before 2:00 a.m. on 17 April 2020 a powerful transport trailer, accompanied by dozens of technical and security vehicles, passed the gates of the I [...]

    Read more

Of Interest

See archived entries

Vacuum vessel repair

A portfolio

Whether standing vertically in the Assembly Hall or lying horizontally in the former Cryostat Workshop now assigned to component repair operations, the non-conformities on three vacuum vessel sectors are undergoing similar treatment: the depressions along the bevel joints, where sectors are to be welded to one another, are filled with metal, while the "bumps" are machined in order to restore geometry to nominal. Following close to one year of study and preparation, repair work on sector #7 began in the Assembly Hall in March and is expected to be completed by late August. Sector #6 should follow soon afterwards. As for Sector #8, the most affected of the three, repair work in the former Cryostat Workshop started in earnest a few weeks ago.

Up to three milling machines can operate simultaneously on one sector bevel (here, at the lower section of sector # 6). Repair work on sector #7 began in the Assembly Hall in March and is expected to be completed by late August. Sector #6 should follow soon afterwards. As for Sector #8 repair work started in earnest a few weeks ago in the former Cryostat Workshop. (Click to view larger version...)
Up to three milling machines can operate simultaneously on one sector bevel (here, at the lower section of sector # 6). Repair work on sector #7 began in the Assembly Hall in March and is expected to be completed by late August. Sector #6 should follow soon afterwards. As for Sector #8 repair work started in earnest a few weeks ago in the former Cryostat Workshop.
Metal build-up operations on the bevels of sector #7 passed the 95% mark last week and machining is half-way to completion. Work is a little less advanced on sector #6, with approximately 65% of build-up done and machining just beginning. Metal build-up, which is done manually on sectors #7 and #6, is a delicate operation that demands extreme concentration to achieve uniformity, homogeneity and reliability. It is also a lengthy one —no less than 24 kgs of metal fill-up need to be deposited, pass after patient pass, on the bevels of both sectors. The repairs on sector #8 will require significantly more fill-up and, as a consequence, the process will be partly automated. A massive support structure is now in place inside the component to support the automated welding machine which will be installed this week.

Machining is an automated but no less lengthy process. The milling heads that shave the excess metal have to be positioned with micrometric precision along a series of predetermined positions along the bevel. Each position requires approximately 10 days to be fully machined and there are thirteen successive positions to cover on each side of every sector. Three milling machines can be operating at the same time at different locations on the same sector.

The nature of the work, both a painstaking craft and an industrial process, is illustrated in the gallery below.



return to the latest published articles