Mechanical design and analysis of joints for the ITER PF coils

The Poloidal Field (PF) coils of the International Thermonuclear Experimental Reactor (ITER) are designed with NbTi cable-in-conduit conductors (CICCs) wound in double pancakes which are connected in series by joints. These joints have to operate in the poloidal magnetic field which generate large varying forces. The conceptual design of the joints is based on the overlap concept with twin-boxes and includes a tie-bar to carry the tensile load and a clamping support to resist the radial and vertical loads. The mechanical analysis is performed with several finite-element models of the joint area. It is shown that the design allows to keep both the tensile stress in the conductor and the shear stress in the insulation within acceptable limits.