Stay tuned for a remarkable lift

Vacuum vessel sector #6 will always have a special place in the ITER story. Of the nine sectors that will form the torus-shaped plasma chamber, it was the first to be received (in August 2020), the first to get fitted with instrumentation, the first to be upended to vertical, and the first to be docked in a standing sector sub-assembly tool.

The 440-tonne double-walled steel sector manufactured by Hyundai Heavy Industries and supplied by the Korean Domestic Agency for ITER spent just about one year in vertical tooling, as elements were added to create the first complete "sub-assembly" of the vacuum vessel. A complete set of vacuum vessel thermal shielding plus two toroidal field magnet coils were positioned with the highest degree of accuracy and adjusted with precision by the actuators of the tool.

Lessons learned with these first-of-a-kind operations have already facilitated work on subsequent sectors.

Now, the ITER Organization construction teams, including the TAC-2 assembly contractor DYNAMIC, are preparing for the crowning event in the sequence—the transfer by overhead crane of the 1,250-tonne, 40° section from tooling into the Tokamak assembly pit.

The final preparatory rigging activities are underway.

Because the 40° section must be lifted over the rim of the bioshield on its way to the pit—and because the large mass to be lifted necessitates the use of a rigging attachment called the "dual crane heavy lifting beam" that adds to the height of the ensemble—the lift will be one of the tallest assemblies to be handled by the overhead crane system.

In the 3D animation above, you can see how the different rigging elements combine to carry out the necessary steps, from extraction from the tool, to rotation, transfer, and descent.

-          The dual crane heavy lifting beam (in yellow) allows the cranes to work in tandem and facilitates the rotation of the sub-assembly from its tooling orientation to the orientation required for installation in the pit.

-          The sector lifting tool (in grey, directly underneath) connects directly to the beam supporting the sub-assembly, and has a balancing control system to precisely position the load's centre of gravity.

-          The radial beam that supports the assembly directly, and which played a role in docking the vacuum vessel sector in tooling, is designed to continue to support the sub-assembly during in-pit sector-to-sector welding by bracing itself between the tall centre column in the pit and brackets on the surrounding wall.

This long-planned operation is imminent. At the centre of the first-completed sub-assembly of the ITER vacuum vessel, sector #6 will once again be a trailblazer.

The animation is also on the ITER Organization's YouTube page (courtesy of Brigantium Engineering).