Superconducting magnet development

A major milestone in the international Large Coil Task (LCT) was reached in October 1985, when experimental operation of a six-coil toroidal array of superconducting test magnets was begun. During the first months of the year, work in the International Fusion Superconducting Magnet Test Facility (IFSMTF) consisted of installing the five completed test coils and the system of remotely movable pulse coils. Meanwhile, Westinghouse encountered a technical problem with one component of its coil, which delayed delivery until August. This placed extreme schedule pressure on its installation in the IFSMTF. Foreign participants in the LCT expressed grave concern to the Department of Energy, which was allayed only when extraordinary effort by the ORNL Fusion Energy Division, the Engineering Division of Martin Marietta Energy Systems, Inc., and the Y-12 Maintenance Division resulted in installation of the Westinghouse coil and remaining equipment and closing of the vacuum tank by the date that had been promised before the setback at Westinghouse occurred. Following the closure of the 11-m-diam tank housing the test array, a satisfactory vacuum was achieved, and cooldown to the required cryogenic operating temperature was started in December. There were some delays due to problems with the helium compressor system, and the cooldown was interrupted for replacement of a leaking helium heat exchanger. On the whole, however, at the end of the year, prospects were good for achievement of all the goals of the LCT test program within a reasonable period of time. Concurrently with the mainline effort on the LCT, development of advanced superconductor concepts continued at a modest level