5th solenoid module heads to ITER

Manufactured by US subcontractor General Atomics on behalf of US ITER, this 110-tonne central solenoid module magnet is being loaded for transport to the port of Houston.

The ITER central solenoid is the giant electromagnet at the centre of the ITER machine that will generate most of the magnetic flux charge of the plasma, initiating the initial plasma current and contributing to its maintenance. Six individual coil modules will be stacked vertically within a "cage" of supporting structures. General Atomics will also produce a seventh module as a spare.

Each central solenoid module was wound from approximately 6,000 metres of niobium-tin (Nb3Sn) conductor supplied by the Japanese Domestic Agency. (See a photo reportage of production at General Atomics here.) Four have already been received on site at ITER and are assembled one on top of another in the ITER Assembly Hall. Once all six are stacked, a support structure will be built around the tower—including 18-metre-tall tie plates that run the full height of the central solenoid assembly (9 interior and 18 exterior) and that connect at top and bottom to massive upper and lower "key blocks."