GB1365368A - Cryostat - Google Patents

Abstract

1365368 Cryostats KERNFORSCHUNG mbH GES FUER 14 Oct 1971 [14 Oct 1970] 47903/71 Heading F4H A cryostat for use in cooling superconducting magnetic coils to very low temperatures for ionoptical devices, comprises a double-walled tube 2 having thermal insulation 3 and a doublewalled tube 4 having an evacuated interior space 5; the surfaces 6 of the tubes 4 being coated with a metallized plastics material foil which prevents the escape of gas. The space between the double-walled tubes 2 and 4 is cooled with liquid nitrogen 7 over which a nitrogen atmosphere 8 is formed. A closure member 13, which is formed so as to be capable of acting as an interconnecting member between two cryostats when connected in series or between a cryostat and an end piece when located at the end of an arrangement, is secured to the double-walled tubes by screws 17. The body to be cooled, shown as consisting of a hollow winding support 18 and a coil arrangement 19, is surrounded by liquid helium 20 over which a helium atmosphere 21 is located. A vacuum chamber 22, supported on the winding support 18 is located adjacent the closure member 13. When the member 13 is located at the end of an arrangement, on additional thermal insulating space in the form of an end-piece 37 is provided. The closure member 13 consists of three discs 24, 25, 26 connected with one another by adhesive. Bores and passages are provided in the discs to supply and exhaust liquid helium and liquid nitrogen to the spaces 20, 7 respectively. Electrical current is supplied to coil via energy supply conduits which extend in the plane of the closure member 13 in a similar manner to the bores and passages. Since the closure member is of a highly insulating material and the conduits do not pass through the jacket of the cryostat, then the formation of heat bridges is avoided.