Procurement Arrangement 44 for ITER's thermal shields

On Monday, 17 May, Procurement Arrangement #44 for ITER's thermal shield system was signed between the ITER Organization and the Korean Domestic Agency. The thermal shields, a key component for the successful operation of ITER, minimize the heat loads transferred by thermal radiation and conduction from the warm components inside the tokamak to the components and structures that operate at 4.5 K. The shields themselves will operate at approximately 80 K.

The thermal shield system is made of single-wall stainless steel panels with the cooling pipes welded to the panels. The panels are cooled by 1.8 MPa pressurized helium gas supplied by the cryoplant. Thermal radiation to the superconducting magnets confining the plasma is further reduced by providing a 5 μm thick, low emissivity silver coating on both sides of the shield plates. The shield's surface area covers 5,000 square metres and, once assembled, will stand 25 metres at its highest point.

The contract was signed by ITER Director-General Kaname Ikeda on behalf of the ITER Organization and the Director of the Domestic Agency Kijung Jung on behalf of the Republic of Korea. The component will be manufactured under the supervision of the National Fusion Research Institute and is expected to be delivered to the ITER construction site in southern France by late 2016.