The ITER port limiter design

The limiters in the International Thermonuclear Experimental Reactor (ITER) have been relocated to equatorial ports in order to improve their operability and maintenance. This position reduces to a minimum the total first wall (FW) area subjected to high heat fluxes with resulting savings in component costs along with those in the associated cooling water system. Installation in the ports allows the limiter position to be adjusted from outside the cryostat and greatly simplifies the remote handling tasks required for their replacement. Since all attachments to the device structure, vacuum seals and utilities are at the rear surface of the limiters and accessed through the port, no connector access gaps are required in the plasma facing surface and local hot spots are eliminated. For the limiter module design, an innovative design has been adopted that avoids rather than withstands the large electromagnetic (e.m.) shear loads previously occurring at this position. The design also minimises the thermal stresses.