Abstract: An assembly for closure of an opening into a vessel, has a valve chamber, a valve biased toward a closed position in which the valve closes the first opening, and a retainer that retains the valve in an open position. A flow of cryogen from a first opening through the valve chamber to a second opening acts to displace the retainer and allow the valve to close.

Abstract: An assembly comprising has a two-stage cryogenic refrigerator and an associated mounting arrangement, and comprising a sock having first and second stages corresponding to first and second stages of the refrigerator, wherein with the first stage of the refrigerator being in thermal contact with the first stage of the sock and the second stage of the refrigerator being in thermal contact with the second stage of the sock.

Abstract: An assembly comprising has a two-stage cryogenic refrigerator and an associated mounting arrangement, and comprising a sock having first and second stages corresponding to first and second stages of the refrigerator, wherein with the first stage of the refrigerator being in thermal contact with the first stage of the sock and the second stage of the refrigerator being in thermal contact with the second stage of the sock.

Abstract: An assembly has a two-stage cryogenic refrigerator and an associated mounting arrangement, and a sock having first and second stages corresponding to first and second stages of the refrigerator, with the first stage of the refrigerator being in thermal contact with the first stage of the sock and the second stage of the refrigerator being in thermal contact with the second stage of the sock.

Abstract: An abstract for a quench valve of a cryostat, in particular for use in a magnetic resonance imaging system, is attachable to the quench valve so as to raise the cracking pressure of the quench valve without changing the operability of the quench valve. Such an accessory device is usable to enable the cryostat, containing a cryogen, to be safely transported by air transportation.

Abstract: In a cryostat, in particular for use in a magnetic resonance imaging (MRI) system, and a method for reducing heat input into such a cryostat, an insert is provided that is adapted to be inserted into an opening of the cryostat. The insert is adapted to provide one or more passageways for a cryogen through the opening by defining at least one space between the outer surface of the insert and at least one part of the inner surface of the opening. This space allows the cryogen to pass over the part of the inner surface of the opening.

Abstract: A mechanical actuation arrangement for remotely applying a force to a cryogenically-cooled device has a mechanical actuator composed of multiple parts. In use, the parts bear against one another to enable a force to be applied to the device by an actuator device, and when not in use, the parts separate.

Abstract: An assembly for closure of an opening into a vessel, has a valve chamber, a valve biased toward a closed position in which the valve closes the first opening, and a retainer that retains the valve in an open position. A flow of cryogen from a first opening through the valve chamber to a second opening acts to displace the retainer and allow the valve to close.

Abstract: A cryostat includes a cryogenic refrigerator arranged to cool the interior of a cryogen vessel within the cryostat, the cryogenic refrigerator being arranged inside a refrigerator sock. A pipe is controlled by a passive temperature-sensitive valve to selectively provide a path for cryogen gas flow through the refrigerator sock. The passive temperature-sensitive valve is controlled according to a temperature of the cryogen gas supplied from the refrigerator sock to the passive temperature-sensitive valve.

Abstract: A cryogen vessel port arrangement for a magnetic resonance imaging (MRI) system has a port for guiding cryogen into a cryogen vessel. The port has a siphon tube, a siphon cone, which is in flow connection with the siphon tube, and a pipe with an inlet opening and an outlet opening. The inlet opening is configured for connecting it with a coldhead sock and the outlet opening is in flow connection with the port and the siphon cone. The port has a port component that has a flow channel with a first opening configured for connecting it with a service siphon, a second opening in flow connection with the siphon cone, and a third opening in flow connection with the outlet opening of the pipe.

Abstract: An abstract for a quench valve of a cryostat, in particular for use in a magnetic resonance imaging system, is attachable to the quench valve so as to raise the cracking pressure of the quench valve without changing the operability of the quench valve. Such an accessory device is usable to enable the cryostat, containing a cryogen, to be safely transported by air transportation.

Abstract: An over-pressure limiting arrangement for a cryogen vessel includes an access neck providing access into the cryogen vessel, a tubular structure extending through the access neck, a turret outer assembly joined leak-tight to the cryogen vessel and defining an interior volume that is separated from the atmosphere by a protective valve or burst disc, enclosing an upper extremity of the access neck and the tubular structure. An egress path defines a route for cryogen gas to escape from the turret outer assembly, and a pressure-responsive quench valve seals the egress path and opens when a differential pressure between the interior of the turret outer assembly and the interior of the egress path exceeds a predetermined value. An auxiliary burst disc, or a valve, is attached to the tubular structure within the turret outer assembly, with an inner surface thereof exposed to the interior of the tubular structure and an outer surface thereof exposed to the interior of the turret outer assembly.

Abstract: A cryogen vessel port arrangement for a magnetic resonance imaging (MRI) system comprising a port (30) for guiding cryogen into a cryogen vessel is described. The port (30) comprises a siphon tube (32), a siphon cone (33), which is in flow connection with the siphon tube (32), and a pipe (34) with an inlet opening (35) and an outlet opening (36). The inlet opening (35) is configured for connecting it with a coldhead sock and the outlet opening (36) is in flow connection with the port (30) and the siphon cone (33). The port (30) comprises a port component (40) which comprises a flow channel (44) with a first opening (41) configured for connecting it with a service siphon (53, 63), a second opening (42) which is in flow connection with the siphon cone (33), and a third opening (43) which is in flow connection with the outlet opening (36) of the pipe (34).

Abstract: A mechanical actuation arrangement for remotely applying a force to a cryogenically-cooled device has a mechanical actuator composed of multiple parts. In use, the parts bear against one another to enable a force to be applied to the device by an actuator device, and when not in use, the parts separate.

Abstract: An assembly has a two-stage cryogenic refrigerator and an associated mounting arrangement, and a sock having first and second stages corresponding to first and second stages of the refrigerator, with the first stage of the refrigerator being in thermal contact with the first stage of the sock and the second stage of the refrigerator being in thermal contact with the second stage of the sock.

Abstract: In a method for cooling a superconducting magnet device suitable for magnetic resonance imaging, and a cooling system, a small quantity of cryogen is used by cooling the magnet coils of the magnet device by a cooling pipe assembly, the cooling pipe assembly having one or more cooling pipes through which a cryogen flows. The one or more cooling pipes are in close thermal contact with the magnet coils. Liquid cryogen is filled into a cryogen vessel to provide a cryogenic temperature for at least parts of the magnet device for superconducting operation. The magnet coils are cooled during energizing of the magnet device by this cooling pipe assembly.

Abstract: In a cryostat, in particular for use in a magnetic resonance imaging (MRI) system, and a method for reducing heat input into such a cryostat, an insert is provided that is adapted to be inserted into an opening of the cryostat. The insert is adapted to provide one or more passageways for a cryogen through the opening by defining at least one space between the outer surface of the insert and at least one part of the inner surface of the opening. This space allows the cryogen to pass over the part of the inner surface of the opening.

Abstract: An over-pressure limiting arrangement for a cryogen vessel includes an access neck providing access into the cryogen vessel, a tubular structure extending through the access neck, a turret outer assembly joined leak-tight to the cryogen vessel and defining an interior volume that is separated from the atmosphere by a protective valve or burst disc, enclosing an upper extremity of the access neck and the tubular structure. An egress path defines a route for cryogen gas to escape from the turret outer assembly, and a pressure-responsive quench valve seals the egress path and opens when a differential pressure between the interior of the turret outer assembly and the interior of the egress path exceeds a predetermined value. An auxiliary burst disc, or a valve, is attached to the tubular structure within the turret outer assembly, with an inner surface thereof exposed to the interior of the tubular structure and an outer surface thereof exposed to the interior of the turret outer assembly.

Abstract: A cooled current lead for conducting electrical current into a cooled vessel. The current lead comprises an electrical conductor (22) comprising a region (29) which, in use, is heated by electrical current flowing through it; a cooled component (31) situated above a the region (29) and which is provided with a path for removal of heat; and a thermo-siphon comprising a cavity (35) in thermal contact with both the region of the electrical conductor and the cooled component, said cavity containing a fluid (35).

Abstract: The present invention provides a cryostat comprising a cryogen vessel (1), a thermal radiation shield (2), and a sleeve (5) for accommodating a cryogenic refrigerator. Also provided is a first thermal contact for thermally and mechanically connecting a first stage of a cryogenic refrigerator to the radiation shield for cooling thereof. A secondary recondensing chamber is provided (8) for accommodating a second stage of a cryogenic refrigerator, and means (10; 24) are provided for thermally connecting the secondary recondensing chamber to a recondensing surface (11a; 44) exposed to the interior of the cryogen vessel. The cryostat further comprises a pressure control arrangement (100) for controlling the pressure of a gas within the secondary recondensing chamber.