Review gives green light to pursue ITER cryostat manufacturing

Inaugurated last November, the 5,500-square-meter ITER Cryostat Workshop will not remain empty for long. Later this year, in mid-September, the first batch of the 54 segments of the ITER cryostat (the huge vacuum chamber that insulates the superconducting magnets of the machine) will leave the Larsen & Toubro factory in Hazira, India, to be delivered to the ITER site for welding and assembly.

This first shipment will consist of the six 60° segments that form the first tier of the cryostat base section. The base section is one of four main sections (along with lower cylinder, upper cylinder and top lid) of the 30-meter-tall, 30-meter-diameter component. The cryostat base section—1,250 tons—is the single largest load of ITER Tokamak assembly. It will also be the first component to be installed in the Tokamak Pit when assembly begins.

In April 2013, a first Manufacturing Readiness Review was held for the base section and lower cylinder segments. A second review followed on January 30, 2015, for the remaining items, namely the upper cylinder, top lid, shielding blocks, assembly tooling and transporter frames.

“A Manufacturing Readiness Review consists of a complete review of documents, from drawings to manufacturing guidelines, that ensures that every production step has been carefully observed,” explains Igor Sekachev, the engineer in charge of the cryostat at ITER Organization, who participated in the review along with representatives of ITER India and contractor Larsen & Toubro.

Chaired by S. C. Chetal, former head of the Indira Gandhi Centre for Atomic Research, the panel also assessed the ongoing fabrication of the base section and lower cylinder at the shop floor. “All in all, and as a result of the intense collaborative efforts between the ITER Organization, ITER India and Larsen & Toubro,” adds Sekachev, “everything appears to be beautifully prepared and we gave our green light for the remainder of the manufacturing.”

On-hold items are very few, principally interfacing components that haven’t yet reached a sufficient level of maturity. This is the case for the tokamak cooling water system, the large rectangular bellows, the circular bellows for the neutral beam injectors, and the housings for the torus cryopumps. “We’re all working hard to bring these components to final design in order to release the on-hold items as soon as possible.”