Magnet Test Laboratory Research Articles

Thermal optimum analyses and mechanical design of 10-kA, vapor-cooled power leads for SSC superconducting magnet tests at MTL

Spiral-fan, 10-kA, helium vapor-cooled power leads have been designed for Superconducting Super Collider superconducting magnet tests at the Magnet Test Laboratory. To thermally optimize the parameters of the power leads, the lead diameters, which minimize the Carnot work for several different lengths, two different fin geometries, and two RRR values of the lead materials were determined. The cryogenic refrigeration and liquefaction loads for supporting the leads have also been calculated. The optimum operational condition with different currents is discussed. An improved mechanical design of the 10-kA power leads was undertaken, with careful consideration of the cryogenic and mechanical performance. In the design, a new thermal barrier device to reduce heat conduction from the vacuum and gas seal area was used. Therefore, the electric insulation assembly, which isolates the ground potential parts of the lead from the high-power parts, was moved into a warm region to prevent vacuum and helium leakage in the O-ring seals due to transient cold temperature. The instrumentation for testing the power leads is also discussed.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Construction and installation of the SSC accelerator system string test cryogenic systems

The Superconducting Super Collider Laboratory is installing three cryogenic systems for refrigerating superconducting magnets to the temperature range of 4.2-2.5K. The first of these three systems is dedicated to the Accelerator System String Test (ASST) which simulates the conditions of the Main Ring for a string of five magnets. The second cryogenic system will be installed adjacent to the first, and together they will be used to service the first actual sector (one-tenth) of the Main Ring. The third cryogenic system will be used for magnet performance testing at the Magnet Test Laboratory (MTL) and includes test stands to support five magnet tests running in parallel. This paper describes the cryogenic refrigeration hardware which has been constructed and reports on the progress of the installation and the commissioning of the ASST, MTL and N15B Cryogenic systems.