| 摘要 |
A cryostat arrangement with an outer jacket (1) and a first tank (2) has a first cryogen and a second tank (16) with a second liquid cryogen, which boils at a higher temperature than the first cryogen. The first tank comprises a neck tube (4), whose hot upper end (5) is connected to the outer jacket (1) at ambient temperature and whose cold lower end (6) is connected to the first tank at a cryogenic temperature, is characterized in that a riser pipe (3) protruding into the second tank is provided, through which the second liquid cryogen can flow out of the second tank. The lower end of the riser pipe ends in the second liquid cryogen in the second tank. A first heat exchanger (7) is provided, into which the riser pipe opens directly or indirectly with its upper end. The first heat exchanger has an outflow line (17) through which the second cryogen evaporating from the first heat exchanger can flow out. The first heat exchanger is in thermal contact with the neck tube. The neck tube provides local cooling by means of the second cryogen from the riser pipe. It is thus possible to greatly reduce the heat input originating from the neck tube into the first tank, in particular by using a second cryogen, which is normally much less expensive, wherein the existing equipment may be retrofitted easily. |
