The ISABELLE Magnet Support and Adjustment System

The ISABELLE superconducting magnet is supported at the quarter points within a carbon steel vacuum vessel by four fiberglass straps. These are positioned at a small angle to the vertical so that contraction of both the magnet core and the suspension straps do not change the position of the magnet centerline. Two smaller fiberglass straps at each support provide horizontal position location. The fiberglass straps are fabricated of uniaxial epoxy fiberglass tape. Creep tests at room temperature and 1.3 times design load show no extension after one year and there was a factor of safety of 5 in breaking strength. An Engineering Test Model was constructed and cycled to 5° K. Heat leak for the eight straps was less than 0.5 W and position stability was within ± 0.005¿. The vacuum vessel is vertically positioned by means of three jack screws with sliding pads and spherical washers between the top of the jacks and the support boxes. Longitudinal and lateral positioning is done by three horizontal screws at each support box. Three shim plates on the top of the support boxes are used to set the magnetic plane and sockets in two of these are used to set the lateral plane.