Development of disk fin type compact current leads

This report describes compact current leads for a VENUS superconducting solenoid magnet (operating current of 4.1 kA) at KEK. The disk fins of a special type were devised which are suited to be cut straightly with numerically controlled machines such as wire cutter and milling. Since the straightcut disk fins increase both the heat exchange efficiency and the thermal inertia, they make it possible to construct the current leads compactly. The current leads fabricated were as short as 60 cm. Good performance was achieved experimentally in the heat flow at cold end and the pressure drop of coolant gas. The reliability estimated is equivalent to that of current leads of about twice length in the case of no cooling-fin type. (author)