Applus+ is working with Spanish company Asturfeito to manufacture a cryostat for the JT-60SA nuclear fusion reactor, a project being undertaken under the auspices of the international “Fusion for Energy” consortium, which includes the European Union and Japan. This international project, based in Naka, Japan, aims to deepen knowledge around the production of this energy source.

The work is especially complex given the reactor’s dimensions and the materials from which it is constructed. It is made up of twelve segments, which together measure 15 metres high and 12 metres across and weigh between 400 and 500 tonnes.

The learnings and outcomes from the JT-60SA project will be applied to ITER (the International Tokamak Experimental Reactor), the most important and advanced nuclear project since the Manhattan Project. ITER, which is being rolled out at Cadarache in France, is a joint Japanese, Indian, Korean, Chinese, European and Russian venture that could go into operation in 2025.

 

cryostat for nuclear fusion

 

The cryostat began construction at the end of 2013. It is made of stainless steel and, together with its base (which was built in Avilés, Spain, before being transported to Japan), weighs some 260 tonnes.

Applus+, which played a role in the manufacture of the base, is now responsible for the ultrasonic non-destructive testing and certification of the welds. As such, and given the particular challenges posed by the ultrasonic volumetric inspection of high-thickness austenitic welds, we have launched a new R&D project: Inoxplus. Its goal is to develop the specialist knowledge required to enable inspection teams to work in nuclear fusion facilities, with unfamiliar base materials, through researching, designing and building a semi-automated ultrasonic inspection system.

Applus+ RTD in Rotterdam, with over 20 years’ experience in the manufacture of longitudinal-wave and creeping-wave probes, has been charged with the development of specialist creeping-wave probes for use in this project. Material welding and mechanisation has been particularly challenging owing to the stringent manufacturing tolerances.