Abstract: An elongated cryogenic envelope includes a support-spacer for locating a plurality of refrigeration tubes at selected radial and circumferential locations within a vacuum chamber formed between inner and outer coaxial tubes. The support-spacer includes a high-thermal-conductivity ring surrounding the inner tube and a plurality of hollow epoxy-fiberglass, titanium-tipped spokes extending between the outer tube and the high-thermal-conductivity ring surrounding the inner tube.

Abstract: A superconducting power transmission line is comprised of sections of rigid cryogenic envelope and sections of flexible cryogenic envelope. The rigid sections are comprised of rigid inner and outer tubes having a refrigeration shield located in a vacuum chamber therebetween. The flexible sections are comprised of flexible inner and outer tubes surrounded by reinforcing braid. The rigid and flexible inner and outer tubes are joined together and a refrigeration tube which is in contact with the rigid section's shield is coiled about the inner flexible tube.

Abstract: A liquified gas is transferred from a supply tank to a saddle tank by gravity flow. After a predetermined amount of the liquified gas has been transferred, gravity flow is stopped and pressure is equalized between the saddle tank and the container to be filled. Thereafter, vapor from the container flows into the supply tank causing liquified gas to flow from the saddle tank into the container. After the container has received a predetermined amount of liquified gas, liquid flow ends and pressure is equalized between the supply and saddle tanks.