A cryostat assembly comprises an outer container that houses a coil tank with a superconducting magnet coil system and a first cryogenic fluid, and a storage tank with a second cryogenic fluid. The coil tank is secured to the outer container by a first suspension element and the storage tank is secured to the outer container by a second suspension element. The storage tank is thermally connected to a cover element having a mechanical and thermally-conductive connection to a tube element and to the first suspension element. The cover element connects to the storage tank via a resilient, heat-conducting connection that is in thermal contact with the cover element and the storage tank. This allows thermal coupling between the storage tank and cover element, and independent relative movements between the storage tank and cover element, while suppressing relative movements between the tube element and the superconducting magnet coil system.

The present disclosure relates to using an integrated cooling circuit to provide both forced-flow pre-cooling functionality and closed-loop thermosiphon cooling for persistent mode operation of a superconducting magnet. In one embodiment, the integrated cooling circuit shares a single set of cooling tubes for use with both the forced-flow pre-cooling circuit as well as the closed-loop operating-state cooling circuit.

A fault-tolerant cryogenically cooled system including an outer vacuum chamber defining a vacuum region in its interior volume; a cryogenic refrigerator; equipment to be cooled, housed within the vacuum region; a free volume delimited within the vacuum region and containing a cryogen; a cold plate exposed to the free volume and thermally linked to the equipment to be cooled; a heat exchanger thermally linked to a coldest stage of the refrigerator and exposed to the free volume; a cryogen buffer vessel delimiting a buffer volume; and a passage linking the buffer volume with the free volume.

A sealed container having gloves attached thereto is provided as part of a physical properties measuring system (PPMS). The PPMS includes a sealed pressurized portion that is pressurized with a gas to purge out air from inside the sealed pressurized portion to reduce water vapor inside the sealed pressurized portion below a water vapor threshold. The system further includes a cryogenic tank having a cryostat disposed therein. The cryogenic tank contains a cryogenic liquid cooled to a cryogenic temperature. Test samples are placed inside the sealed pressurized portion in preparation of measuring physical properties of the test samples. One of the test samples is immersed in the cryogenic liquid to measure the physical properties. The test sample is removed from the cryogenic liquid and is exchanged for another test sample inside the sealed pressurized portion to prevent ice formation inside the cryostat.

A split cylindrical superconducting magnet system including two half magnets, each half magnet comprising superconducting magnet coils retained in an outer vacuum chamber, having a thermal radiation shield located between the magnet coils and the outer vacuum chamber, wherein the thermal radiation shield is shaped such that the axial spacing between thermal radiation shields of respective half magnets is greater at their internal diameter than at their outer diameter.

Disclosed are a helium gas liquefier and a method for liquefying a helium gas. The disclosed helium gas liquefier includes: a first cooling part including a first cooling column; a first cold head installed on the first cooling column, and a first cylinder in which the first cooling column and the first cold head are built; a second cooling part including a second cooling column, a second cold head installed on the second cooling column, and a second cylinder in which the second cooling column and the second cold head are built; and a liquid helium storage disposed under the second cooling part.

A super-cooled liquid medium, preferably super-cooled liquid nitrogen, is pumped through a sub-cooler and cooled by the same medium that evaporates in the vacuum. This super-cooled nitrogen is used as coolant for a consumer. If a small amount of heat is emitted by the consumer to the nitrogen, the liquid medium can be guided in the circuit wherein the sub-cooler is arranged. For compensating volume fluctuations, such a circuit requires a compensation vessel, which is very expensive and can only be operated in the presence of a super-cooled medium when either a part of the medium is heated using external energy, or an inert gas which boils at very low temperatures is used as a pressure compensation medium. According to the disclosure, when a supply container for the liquid medium is integrated into the cooling circuit and used as a compensation vessel, a separate compensation vessel is not required.

A superconducting current limiter with a bifilar coil winding made of a T.sub.c superconductor (HTS) conductor in a cryostat that includes a solid filler material, where the solid filling material is particularly formed from a granulate, hollow bodies or an open-pored structure and is surrounded by cryogen.

A cryostat arrangement (1) having a vacuum container (2) and an object (4) to be cooled, which is arranged inside the vacuum container. A neck tube (8) leads to the object, and a cooling arm (10) of a cold head (11), around which a closed cavity (9) is formed, is arranged in the neck tube, which is sealed off fluid-tight in relation to the object and is filled with cryogenic fluid in normal operation. A thermal coupling element (15) couples the cryogenic fluid in the cavity to the object. A pump device (14), to which the cavity is connected via a valve (13) and with which the cavity is pumped out if the cold head fails. A monitoring unit (17) monitors the cooling function of the cold head, and activates the pump device to pump out the cavity if the cooling function of the cold head drops.

The present invention provides acryogenic vessel (200), in particular for use in a magnetic resonance examination system (110) to mount therein superconductive main coils (142, 144) of the magnetic resonance examination system (110), comprising an inner vessel (202), an outer 300K vessel (204), and a radiation shield (206), which is located between the inner vessel (202) and the outer 300K vessel (204) and which surrounds the inner vessel (202), whereby the radiation shield (206) has at least one dry-friction area (206), where dry-friction is generated upon deformation of the radiation shield (206). The present invention also provides a superconductive magnet (114) for a magnet resonance examination system (110) comprising a set of superconductive main coils (142, 144), which are arranged in the above cryogenic vessel (200). The present invention further provides a magnet resonance examination system (110) comprising the above superconductive magnet (122).