Cryostat manufacturing
The week the workshop emptied
20 Apr 2020
For a few minutes, the Cryostat Workshop resounded with Beethoven's "Ode to Joy." It was a strange moment, both solemn and poignant. Before long, the self-propelled trailer transporting the base section of the ITER cryostat began to move towards the mega-door facing the Assembly Hall and, soon, the vast hall that had teemed with activity for almost five years stood empty and silent. It will remain so until the segments of the fourth and final section of the cryostat (the top lid) are delivered in July to be assembled and welded.
On April 15, the cocooned cryostat upper cylinder was moved out of its birthplace to be placed in temporary storage. One year earlier to the day its near-twin, the lower cylinder, had followed the same route.
Two days before, on Wednesday 15 April, the upper cylinder had made a similar exit, but instead of being delivered to the Assembly Hall, it was moved to a dedicated storage area to be positioned next to its near-twin, the lower cylinder.
Watching these two huge components slowly crawl out of their birthplace gave a sense of the exceptional dimensions of the ITER Tokamak. It also signalled just how close ITER is to the beginning of the assembly phase.
Watching the cryostat base section entering the antechamber of the Assembly Hall gave a sense of the exceptional dimensions of the ITER Tokamak.
Once inside the Assembly Hall, directly underneath the beams of the overhead crane, the 1,250-tonne base section appeared ready to undertake the 170-metre-long journey to the mouth of the Tokamak pit.
The ITER cryostat—the largest stainless steel high-vacuum pressure chamber ever built (16,000 m³)—will provide a high vacuum, ultra-cool environment for the ITER vacuum vessel and superconducting magnets. The Indian Domestic Agency has collaborated with main contractor Larsen & Toubro Heavy Engineering (manufacturing design, segment fabrication in India and assembly at ITER); MAN Energy Solutions, Germany (Larsen & Toubro sub-contractor for on-site welding); and SPIE Batignolles TPCI, France (Larsen & Toubro sub-contractor for the realization of the Cryostat Workshop) to deliver the components to specification and on time.
See aerial footage of the transfer operations in the latest ITER NOW video.
And it's only one-third of the Tokamak's height ...
There was just enough space for the upper cylinder—and two days later the base—to exit the Cryostat Workshop. The Workshop will remain empty until the segments of the top lid arrive for assembly and welding in July.
Completed in 10 months
Assembly and welding operations on the cryostat upper cylinder (left) began in the summer of 2019. Ten months later, the massive component was finalized, cocooned and ready to be placed in temporary storage next to its near-twin, the lower cylinder.
A remarkable photo, shot by drone, of three ITER cryostat sections. On the left, the soup-dish-shaped cryostat base, heading into the Cleaning Facility; on the right, the lower and upper cylinders cocooned for outdoor storage. The Indian Domestic Agency, responsible for 100% of the cryostat, has collaborated with main contractor Larsen & Toubro Heavy Engineering (manufacturing design, segment fabrication in India and assembly at ITER); MAN Energy Solutions, Germany (Larsen & Toubro sub-contractor for on-site welding); and SPIE Batignolles TPCI, France (Larsen & Toubro sub-contractor for the realization of the Cryostat Workshop). Photo: ITER Organization/EJF Riche
On 192 wheels
Transported on a self-propelled modular transporter with 192 wheels, the 30-metre-in-diameter, 1,250-tonne cryostat base section slowly crosses from the Cryostat Workshop (left) to the antechamber of the Assembly Hall. The cryostat base will be the first major machine component to be lowered into the machine assembly pit.
Like a starship preparing to cross the galaxy, the base section of the ITER cryostat appears ready to undertake the 170-metre-long journey across the Assembly and Tokamak buildings to the opening of the machine assembly pit. The truth is, it will take a couple of weeks to prepare for the first great act of ITER assembly.