Sector sub-assembly
Twin meets twin
15 Oct 2018
Although they were born one full year apart, they are identical twins: when the second vacuum vessel sector sub-assembly tool (SSAT-2) is complete, nothing will distinguish it from its sibling.
Powerhouse: this 800-tonne tool stands 22 metres tall and can handle a 1,200-tonne subassembly. And it will soon have an identical twin in the Assembly Hall ...
In the vast and resounding Assembly Hall, the first sub-assembly tool is a towering presence: the mechanical structures have all been assembled and work on electrical and hydraulic connexions will soon proceed.
SSAT-2, by contrast, is just hatching—four batches of components, out of a total of six, have been delivered by Korea to the ITER site. Specialists from the French contractor CNIM are busy installing and precisely aligning the toroidal rail tracks upon which the wings of the giant tool will travel, and the first leg segment has been brought in for installation.
Full assembly of the second vacuum vessel sub-assembly tool should be complete by the end of January 2019.
For more pictures and details, check the gallery below.
From the rafters
The technician walking along the curved rails gives us a sense of the tool's scale. The first segment of tool #2 has been positioned for installation.
Twins standing in 2019
The double giants will be capable of steadying 440-tonne vacuum vessel sectors vertically, while two toroidal field magnets (310 tonnes each) and thermal shield segments are rotated inward and secured. The tools will be tested with dummy loads next year.
Tool #1
All the pieces of the first tool are in place; only hydraulic and electrical connections must be installed. Ahead are functional tests (integrated system tests without the test load), followed by full-load tests.
Load tests next year
Both tools will be tested with a full-weight dummy load, expected on site in March 2019. Load testing is the final tool qualification activity, allowing operators to verify the tools' ability to accurately adjust the dummy load toroidally and to six degrees of freedom within tolerances of +/- 1 millimetre.
The advantage of lessons learned
Final adjustments are made to the curved rails that will allow the tools' wings to travel inward. Because of lessons learned in the assembly of the first tool, the installation of SSAT #2 will proceed quickly and be completed in January 2019.
First segment positioned
Four batches of SSAT #2 components out of six have arrived on site, and the French company CNIM (local contractor to Korean manufacturer Taekyung Heavy Industries) is starting assembly activities.