Mechanical design of the ISP device

A sliding joint in the toroidal field (TF) coil of a compact tokamak is used to reduce the amount of the vertical separating force usually supported by the inner leg of the coil. The resulting lower stress permits a smaller allocation of space for the inner leg. This, coupled with reduced design objectives, results in a machine that is significantly smaller than the original Tokamak Fusion Core Experiment (TFCX) designs. Additional benefits of a sliding joint are the ability to have the vacuum vessel and poloidal coils prefabricated and completely assembled before installation. The ohmic heating (OH) solenoid is located inside the TF coil and is manufactured as a monolithic assembly along with the TF inner leg conductor bundle. There are at least two promising candidates for a sliding joint that have had preliminary testing, but a foolproof joint configuration has not yet been found