ITER first wall/shield blanket

The blanket system comprises first wall/shield modules which are supported on a structural shell called a back plate containing water channels for cooling the modules. A modular design of the first wall/shield was chosen to allow independent maintenance through the horizontal mid-plane ports using in-vessel remote handling equipment. The modules are mechanically attached to the back plate for assembly and maintenance. The first wall/shield modules can be replaced with breeding modules for the EPP. In the first wall (FW) region, the water is contained in 316 LN stainless steel pipes surrounded by a copper heat sink except in high heat flux regions where copper pipes with a stainless steel liner are used in the limiter and baffles. The plasma facing surface of the FW will be beryllium except for the lower region of the baffles, where tungsten is used. Electromagnetic analysis and structural analysis has been performed on the back plate and FW/shield modules during a plasma disruption and for a VDE with toroidally asymmetric halo currents. A major R and D project is being conducted to provide needed input for design of the blanket system and to confirm the fabrication technology. (orig.)