| abstract |
A method for converting a cryostat assembly (1) with room temperature vacuum container (10), in which a first container (2) with a liquid-helium bath (3) whose operating temperature is maintained by helium evaporation below 5 K, and a second container (6) is arranged, which is filled for thermal shielding of the first container with liquid nitrogen (7) and held by nitrogen evaporation at an operating temperature of 80 K, is characterized in that one at a temperature of 60 K and a Pressure of 1 bar fluid cooling medium (12) is introduced into the second container, which is cooled by a refrigerator (16) by means of a cooling circuit (11), the coolant lines into the second container in, to an operating temperature of ≤ 60 K. Thus, as a retrofit for existing Kryostatanordnungen which use both liquid helium and liquid nitrogen to cool a superconducting coil, the use of liquid nitrogen with a retrofit system completely avoided and additionally the evaporation rate of the liquid helium can be significantly reduced, without reliquishing the used cryogens to have to. |