Testing of Compact Bolted Fasteners with Insulation and Friction-Enhanced Shims for NCSX
Authors: L. E. Dudek, J.H. Chrzanowski, G. Gettelfinger, P. Heitzenroeder, S. Jurczynski, M. Viola and K. Freudenberg
Abstract:
The fastening of the National Compact Stellarator Experiment's (NCSX) modular coils presented a number of
engineering and manufacturing challenges due to the high magnetic forces, need to control induced currents, tight
tolerances and restrictive space envelope. A fastening method using high strength studs, jack nuts, insulating spacers, bushings and alumina coated shims was developed which met the requirements. A test program was conducted to verify the design. The tests included measurements of flatness of the spacers, determination of contact area, torque vs. tension of the studs and jack nuts, friction coefficient tests on the alumina and G-10 insulators, electrical tests, and tension relaxation tests due to temperature excursions from room temperature to liquid nitrogen temperatures. This paper will describe the design and the results of the test program.
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Presented at: 23rd Symposium on Fusion Engineering, San Diego, CA May 31-June 4, 2009
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Download PPPL-4452 (pdf 207 KB 4 pp)
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