In order to obtain a highly versatile superconducting cable capable of absorbing differences in thermal contraction amounts that arise between three members, these being a cable core, an inner tube, and an outer tube, and to obtain a superconducting cable manufacturing method of the same, a superconducting cable includes a thermal insulation vacuum tube and a cable core. The thermal insulation vacuum tube includes an inner tube fixed at both ends and having a cooling medium filled inside, and an outer tube disposed at an outer peripheral side of the inner tube with a space between the outer tube and the inner tube maintained at a vacuum, and is configured to include a winding section wound with one or more turns. The cable core is fixed at both ends and disposed inside the inner tube.

A bushing includes an insulating housing, an electrical conductor, extending through the housing and an insulating fluid in the housing, wherein the insulating fluid has a viscosity at a temperature of 100? C. of equal or less than 2 mm.sup.2/s. The bushing includes a condenser body surrounding the electrical conductor, wherein the condenser body includes electrically insulating layers and electrically conductive layers, wherein the electrically insulating layers are formed from a paper impregnated with the insulating fluid.

A bushing includes an insulating housing, an electrical conductor, extending through the housing and an insulating fluid in the housing, wherein the insulating fluid has a viscosity at a temperature of 100? C. of equal or less than 2 mm.sup.2/s. The bushing includes a condenser body surrounding the electrical conductor, wherein the condenser body includes electrically insulating layers and electrically conductive layers, wherein the electrically insulating layers are formed from a paper impregnated with the insulating fluid.

A dielectric material with heat transfer properties includes a first fluid and a second fluid different from the first fluid and miscible with the first fluid. The first fluid and the second fluid are mixed with each other so as to form a mixture and are kept at a temperature and a pressure so that the mixture is maintained in a supercritical phase. The mixture has at least one parameter that is preferably different from a corresponding parameter in both a supercritical phase of the first fluid and a supercritical phase of the second fluid. In a method of insulating electrical contacts and removing heat therefrom, the mixture is disposed about the electrical contacts and is maintained at a temperature and at a pressure that causes the mixture to be in a supercritical phase so that the mixture has favorable dielectric and heat transfer properties.

A dielectric material with heat transfer properties includes a first fluid and a second fluid different from the first fluid and miscible with the first fluid. The first fluid and the second fluid are mixed with each other so as to form a mixture and are kept at a temperature and a pressure so that the mixture is maintained in a supercritical phase. The mixture has at least one parameter that is preferably different from a corresponding parameter in both a supercritical phase of the first fluid and a supercritical phase of the second fluid. In a method of insulating electrical contacts and removing heat therefrom, the mixture is disposed about the electrical contacts and is maintained at a temperature and at a pressure that causes the mixture to be in a supercritical phase so that the mixture has favorable dielectric and heat transfer properties.

A high-voltage insulator has at least two separate insulators that can be joined to create a post and that each have an essentially rotation-symmetrical support tube made of glass-fiber-reinforced epoxy resin and having an empty internal space, respective top and bottom metallic flanges that surround top and bottom ends of the respective support tube and close the respective tube's empty internal space with an air-tight seal relative to the outer atmosphere, and a shielding of silicone that fits around each support tube. A tubular coupling piece connects the at least two insulators in such a way that the respective empty internal spaces of the at least two insulators form a common gas space and pressure between the spaces is equalized through the coupling piece.

A high-voltage insulator has at least two separate insulators that can be joined to create a post and that each have an essentially rotation-symmetrical support tube made of glass-fiber-reinforced epoxy resin and having an empty internal space, respective top and bottom metallic flanges that surround top and bottom ends of the respective support tube and close the respective tube's empty internal space with an air-tight seal relative to the outer atmosphere, and a shielding of silicone that fits around each support tube. A tubular coupling piece connects the at least two insulators in such a way that the respective empty internal spaces of the at least two insulators form a common gas space and pressure between the spaces is equalized through the coupling piece.

A dielectric material with heat transfer properties includes a first fluid and a second fluid different from the first fluid and miscible with the first fluid. The first fluid and the second fluid are mixed with each other so as to form a mixture and are kept at a temperature and a pressure so that the mixture is maintained in a supercritical phase. The mixture has at least one parameter that is preferably different from a corresponding parameter in both a supercritical phase of the first fluid and a supercritical phase of the second fluid. In a method of insulating electrical contacts and removing heat therefrom, the mixture is disposed about the electrical contacts and is maintained at a temperature and at a pressure that causes the mixture to be in a supercritical phase so that the mixture has favorable dielectric and heat transfer properties.

A dielectric material with heat transfer properties includes a first fluid and a second fluid different from the first fluid and miscible with the first fluid. The first fluid and the second fluid are mixed with each other so as to form a mixture and are kept at a temperature and a pressure so that the mixture is maintained in a supercritical phase. The mixture has at least one parameter that is preferably different from a corresponding parameter in both a supercritical phase of the first fluid and a supercritical phase of the second fluid. In a method of insulating electrical contacts and removing heat therefrom, the mixture is disposed about the electrical contacts and is maintained at a temperature and at a pressure that causes the mixture to be in a supercritical phase so that the mixture has favorable dielectric and heat transfer properties.

A wall bushing, comprising a head assembly, a conductive rod, and a connecting terminal sealing and covering the head assembly and the conductive rod. The connecting terminal and the conductive rod are electrically connected. The head assembly includes a transition tank and a transition plate that are connected to each other. An upper end of the transition tank is provided with a first through hole, and a lower end of the transition tank is hole-through. The transition plate is provided with a second through hole. The conductive rod extends through the first through hole and the second through hole. The transition tank and the transition plate are fixedly connected such that an accommodation cavity is formed around the conductive rod and in the transition tank.