Mechanical preloading of the Central Solenoid Model Coil

The inner and outer modules of the Central Solenoid Model Coil (CSMC) are mechanically compressed by a preload structure. The necessary preload is determined for the support of the modules´ terminal leads. The forces in the preload structure are monitored by strain gauge bridges mounted to each of the structure´s 16 inner and 16 outer tension rods during: (1) room temperature loading; (2) cool-down to the coil´s operating temperature; and (3) electromagnetic operation. The preload structure is described and the variations in the preload with each stage of coil operation are presented. Analytical models are presented, which use the observed variations in preload to deduce equivalent mechanical properties for the coil modules