By Udbhav Bhargava

The cryostat base built by Indian tech giant Larsen & Toubro (L&T) has been successfully lifted and put in the ITER reactor facility in France, marking a significant milestone in the field of nuclear engineering. 

ITER (International Thermonuclear Experimental Reactor) is an international research megaproject in nuclear fusion engineering. It is an experimental “tokamak” nuclear fusion reactor being constructed in southern France, next to the Cadarache site. It would be the first industrial-scale fusion reactor and will shed light on the way hundreds of thousands of years of generating safe, inexpensive, and plentiful electricity. This will begin, by 2025, to produce a molten mass of “plasma” electrically charged gas within the reactor core.

The program comprises of seven-member countries that fund the enormous 25 billion USD project. The countries are the European Union (included as one unit), USA, China, India, Japan, Russia and South Korea.

India, formally included in the ITER project in 2005, is responsible for delivery of several key apparatuses and machinery systems such as cooling water system, cryogenic system and heating systems, power supplies and some diagnostics and the cryostat as well. The intellectual manpower of the country is also giving its contribution in the successful completion of the project; more than 100 Indian nuclear scientists are involved in the project.

The cryostat is analogous to the nuclear reactor container that is used in a fission-based nuclear power plant. The cryostat contains the vacuum-tightened container around the experimental vacuum vessel and the superconducting magnetic material and functions as a very massive refrigerator in principle. The purpose of the Cryostat is to provide fusion reactor with cooling, and to keep very extreme temperatures under control at its core. The ITER cryostat is to be the first high-vacuum pressure chamber in the world. The Cryostat frame that is referred as the Top Lid or Cap, weighing more than 600 metric tons, will be mounted along with other components of the Cryostat. Also for Cryostat, L&T already supplied the base section, the lower cylinder and the upper cylinder.

The Cryostat is a proud specimen of the technological might and the Make in India Program and its importance stems from the fact that the fusion reaction will take place inside this gigantic container under controlled conditions. It will be a fully welded stainless steel cylindrical vacuum pressure chamber that is 29 meters in height, has a diameter of 29.4 meters and weighs 3,850 metric tons. The number are a symbol of its enormity. It is the largest structure made up of steel in terms of size and a marvel of Indian engineering.