Power

Nuclear fusion

Overview of the Joint European Torus (JET) at Culham, UK

The equipment for nuclear fusion experimentation brings it's own particular fabrication problems. Joints to be welded may be thick, or thin, or both and be in special stainless steel, copper and nickel alloys as well as conventional steels. The common requirement is for the welded joints to be of the highest quality despite the challenging materials, joints and welding positions that are often found in fabricating the large items of plant.

TWI is able to contribute in this area by offering optimised arc, laser, electron beam, friction and hybrid joining technologies many of which have been specifically developed for this work.

The technology areas of TWI of relevance to nuclear fusion plant are:

Advanced manufacturing techniques aimed at thermonuclear fusion experiment applications

TWI is actively involved with the development of Reduced Pressure Electron Beam welding. This is being explored primarily for the on-site fabrication of the 29m diameter, 80mm thick cryostat vessel, where several circumferential welds are required. The RPEBW process offers the benefits of being much faster than other techniques, and the simpler joint preparation requirement does not lead to the generation of dust in the cryostat. It is expected that the RPEBW equipment will also be employed for welding a number of other on-site joints, particularly in sections from 50mm to 100mm.
Current involvement in the International Thermonuclear Experimental Reactor ( ITER).