Enable Recite

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

  • Data | Archiving 20 gigabytes per second—and making it usable

    One of the main deliverables of ITER is the data itself—and there will be a tremendous amount of it to store and analyze. During First Plasma, the highest produ [...]

    Read more

  • Electrical tests | High voltage, high risk

    In the southern part of the construction platform, a one-hectare yard hosts some of the strangest-looking components of the entire ITER installation. Rows of to [...]

    Read more

  • Vacuum vessel | First sector safely docked

    It was 8:00 p.m. on Tuesday 6 April and something quite unusual happened in the ITER Assembly Hall: applause spontaneously erupted from the teams that h [...]

    Read more

  • Remote ITER Business Meeting | Virtual interaction, tangible opportunities

    While the advent of Covid-19 has not stopped the relentless advancement of the ITER Project, it has certainly prompted ingenuity in how ITER conducts its work. [...]

    Read more

  • Manufacturing | Europe completes pre-compression rings

    The French company CNIM (Toulon) has produced a tenth pre-compression ring for the ITER Project on behalf of Fusion for Energy, the European Domestic Agency. Th [...]

    Read more

Of Interest

See archived entries

Pre-compression rings

An iron fist - in reverse

Knowing that the large electromagnetic forces at work during machine operation would cause stress over time to ITER's largest magnet set, engineers devised a compression system to "push back." The resilience of the solution—large composite "pre-compression" rings that will encircle the tips of the toroidal field coil cases at top and bottom—is about to be tested at a dedicated facility. 

This unusual test bench has 36 actuators exerting a force of 1,000 tonnes each. They will operate simultaneously to subject the toroidal field coil magnet system's pre-compression rings to ITER-like forces in order to test their resistance and durability. (Click to view larger version...)
This unusual test bench has 36 actuators exerting a force of 1,000 tonnes each. They will operate simultaneously to subject the toroidal field coil magnet system's pre-compression rings to ITER-like forces in order to test their resistance and durability.
At a brand-new facility at CNIM (La Seyne-sur-Mer, France) everything is ready for the arrival of an exceptional test bench, capable of applying stresses similar to those of ITER operation to the toroidal field coil pre-compression rings and measuring millimetric deformation.

The tool, developed by Douce Hydro (France) in collaboration with CNIM, will subject the rings to a combined circumferential force of 36,000 tonnes while maintaining a positional accuracy of 0.1 mm. The test on each ring will last a few hours and will be supplemented by other tests to confirm creep and fatigue performance.

The ITER Organization is procuring the test facility and tooling through a contract awarded to the CNIM/Douce Hydro consortium, while the European Domestic Agency has developed the conceptual design of the test facility and is responsible for technical progress.

Neil Mitchell, ITER Magnet Division head, cites the collaboration as "an excellent example of ITER Organization and the European Domestic Agency working as a single team to construct the facility within budget and to schedule."

At a newly created facility at CNIM, representatives of ITER, the European Domestic Agency, manufacturer Douce Hydro and host CNIM stand before the test bench where nine pre-compression rings will be tested (three upper, three lower and three spare). (Click to view larger version...)
At a newly created facility at CNIM, representatives of ITER, the European Domestic Agency, manufacturer Douce Hydro and host CNIM stand before the test bench where nine pre-compression rings will be tested (three upper, three lower and three spare).
The European Domestic Agency is responsible for the fabrication of nine pre-compression rings (three top, three bottom and three spare). Weighing roughly 3 tonnes each, with an inner diameter of 5 metres, they are made of a fiberglass composite that consists of more than one billion minuscule glass fibres glued together using epoxy resin. This material—the result of an in-depth R&D program—has proved to be the best material for withstanding high loads and avoiding the circulation of current.

The first full-scale prototype should be delivered to the test facility by the European Domestic Agency before the end of the year.  Eventually all nine of the pre-compression rings will be proof tested before installation.

Read the original report on the European Domestic Agency website.


return to the latest published articles