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2014 2013


The first cryostat segments arrived in late 2015 from India. Welding operations got off to a start in September 2016. (Click to view larger version...)
The first cryostat segments arrived in late 2015 from India. Welding operations got off to a start in September 2016.
In the northeast corner of the ITER platform, the 6,000-square-metre Cryostat Workshop was built to house the assembly of the four main cryostat sections from 54 smaller segments manufactured in India.

The cryostat is the vacuum-tight container that will surround the ITER vacuum vessel and superconducting magnets. The base section of the cryostat will be the first large component installed in the Tokamak Pit and the top lid of the cryostat will be the last, set into place after the installation of the vacuum vessel, magnets, thermal shielding and central solenoid.

Like the largest poloidal field coils, the size and weight of the main cryostat segments makes travel along the ITER Itinerary impossible. The cryostat base section—1,250 tonnes—is the single largest load of ITER Tokamak assembly; the lower cylinder, upper cylinder and top lid weigh in the range of 600-800 tonnes each. The completed cryostat will measure nearly 30 metres in diameter and as many in height.

As soon as the Tokamak and Assembly buildings and their heavy-lift crane are available, the cryostat base must be ready ... and the lower cryostat cylinder soon after that. A gap of about two years will then follow before the upper cylinder and top lid can be assembled in the Tokamak Pit.

Assembly operations in the Workshop will take place on two 30 x 30 metre platforms that will also act as transporters: once completed, the sections will leave the building on their platforms and travel by rail the short distance to the Assembly Building. Approximately 50 people are expected to manage operations during assembly of the cryostat segments.

The ITER cryostat is the procurement responsibility of the Indian Domestic Agency. The design, fabrication and assembly contract has been awarded to Larsen & Toubro Ltd—this contract also includes the set-up of the Cryostat Workshop, workshop assembly activities, and in-pit assembly (integration of cryostat main sections, welding, etc.).

Cryostat assembly activities are underway now; for more information, visit this page.

Building Facts:

  • Construction: 18 months
  • Length: 110 metres
  • Width: 50 metres
  • Height: 27 metres
  • Number of 30 x 30 metre assembly platforms: 2
  • Building contractor: SPIE Batignolles TPCI
  • Assembly activities begin: 2016
  • First completed section: March 2019 (lower cylinder)
  • Second completed section: July 2019 (base)