Abstract: The invention relates to a device for the additive manufacturing of workpieces under protective gas, which device is provided with a manufacturing chamber designed as a pressure chamber, said manufacturing chamber being fluidically connected to a pressure container via a gas extraction line, which is provided with a vacuum pump, and via a gas return line. After the manufacturing of a first workpiece, the protective gas present in the manufacturing chamber is evacuated, temporarily stored in the pressure container and, prior to the manufacturing of a second workpiece, is introduced into the manufacturing chamber.

Abstract: A device for producing dry ice pellets comprises a pressing cylinder, into which an inlet opening for feeding liquid carbon dioxide leads and which is equipped with a die, which has one or more openings, and with a piston, which is longitudinally movable in the pressing cylinder. Liquid carbon dioxide is fed to the pressing cylinder, is expanded at the inlet opening, is at least partially converted into carbon dioxide snow and is pressed against and through the die by the movement of the piston. The die is in the form of a cylindrical body that can be connected to the pressing cylinder and is equipped with feed-throughs, which are oriented parallel to a longitudinal axis of the die and are dimensioned in such a way that the length and the diameters of the feed-throughs correspond to the length and the diameters of the dry ice pellets to be produced.

Abstract: An apparatus for introducing dry ice pellets into fresh meat comprises a housing, in which an injection device for introducing dry ice pellets is arranged, and guide channels, which lead to a front face of the housing, for guiding a penetration needle, and a drive device for axially moving the penetration needle. A loading unit can be inserted between a rear portion and a front portion of the housing, which loading unit is provided with feedthroughs, which can be equipped with dry ice pellets and brought into a position in alignment with the guide channels. During operation of the apparatus, penetration channels are first produced, by means of the penetration needles, in a piece of meat to be cooled, into which penetration channels the dry ice pellets are subsequently introduced from the feedthroughs using the penetration needles. The feedthrough enables efficient introduction of dry ice pellets into the meat.

Abstract: A cooling system using carbon dioxide as a coolant comprises a cooling chamber for storing products to be cooled during transport and a cooling unit for cooling the atmosphere in the cooling chamber. The cooling chamber and the cooling unit are mounted on or integrated in a cooling vehicle like a truck, a railway wagon or a ship. The cooling unit comprises a carbon dioxide storage compartment and at least one cooling channel through which air is led from and to the cooling chamber. The carbon dioxide storage compartment and the cooling channel are separated from each other by a thermal well-conducting but gas-tight plate serving as a heat exchanger between the carbon dioxide in the carbon dioxide storage compartment and the air in the cooling channel.

Abstract: When welding with a consumable wire electrode, current contacting occurs when the electrode wire passes by a readily electrically conductive contact element. In order to improve the current contacting and reduce the wear of the contact element in particular, the invention proposes subjecting contact elements to a cold treatment prior to using same. The cold treatment has a cooling phase during which the temperature of the contact element is reduced to a lower target temperature, a subsequent holding phase in which the contact element is substantially held at the target temperature, and a final heating phase, in which the contact element is brought to an upper target temperature. The use of contact elements treated using the method according to the invention leads to a substantial increase of the wear resistance compared to untreated contact elements.

Abstract: For charging a refrigerant-receiving compartment of a cooling container with dry ice, a reservoir vessel has a dispensing opening and a dispensing unit which cooperates therewith and by means of which dry ice blocks stored in stacks in a magazine of the reservoir vessel are ejected one after the other from the reservoir vessel and are respectively inserted into a refrigerant-receiving compartment of a respectively provided cooling container. This makes it possible to provide cooling containers in rapid succession with a precisely metered quantity of dry ice as refrigerant.

Abstract: According to the invention, a metal workpiece made by additive manufacturing is subjected, following the additive manufacturing process, to a cold treatment in which the workpiece is cooled to a lower target temperature of less than minus 30° C. in a cooling phase and is then heated up to an upper target temperature in a heating phase. The cold treatment significantly improves the properties of the workpiece in respect of the mechanical quality thereof.

Abstract: A method for recycling argon from an industrial process; in which the gaseous argon is compressed after the use thereof in the industrial process, is fed to a main heat exchanger and is cooled there in contact with a first cooling medium. The compressed and cooled argon is fed to a rectification column or another cryogenic separating device and is liquefied there by direct heat exchange with a second cooling medium and is freed of low-boiling substances by rectification. The liquefied argon is drawn from the bottom of the rectification column and, after use as the first cooling medium in the main heat exchanger, is fed back into the industrial process, the raw argon being brought into thermal contact with cryogenically liquefied pure argon in the main heat exchanger and/or the rectification column. The product argon that results is highly pure and can be fed back to the industrial process.

Abstract: For the transmission of electrical current, determined superconducting current carriers are accommodated in a cryostat, in which they are cooled with an undercooled cryogenic cooling medium, e.g. liquid nitrogen. The current carrier is electrically connected at the ends thereof to two normally conducting current supply means. The cooling medium is undercooled from a storage container to a temperature below its boiling temperature and supplied to the cryostat via a cooling medium inlet, brought into thermal contact with the superconducting current carrier, and subsequently discharged via a cooling medium outlet of the cryostat. According to the invention, the cooling medium from the cryostat is to be used for cooling at least one of the normally conducting current supply means.

Abstract: In a tank filling process for filling a refrigerant tank of a vehicle with a cryogenic refrigerant, firstly a liquefied cryogenic refrigerant stored at a pressure p1 in a storage tank is supplied to a conditioning vessel, subsequently the flow connection between storage tank and conditioning vessel is interrupted, and the pressure in the conditioning vessel is increased, for example by virtue of a flow connection to a pressure build-up vessel being produced, to a pressure p2, wherein p2>p1, whereby the liquefied refrigerant is present in the conditioning vessel in the supercooled state. Subsequently, the supercooled, liquefied refrigerant is supplied to the tank to be filled. By means of the device according to the invention and the process according to the invention, evaporation losses during the filling process can be substantially avoided.

Abstract: The disclosure relates to a device for improving a vacuum in the housing of a machine, in particular a centrifugal-mass energy store, comprising a rotor, for example a shaft having a centrifugal mass arranged thereon, which rotor is supported on at least one superconducting bearing in a contactless manner and is arranged in a vacuum container. In order to maintain the operating state of the superconducting bearing, the superconducting bearing is thermally connected to a cold source cooled by a cryogenic medium. According to the invention, the vacuum in the vacuum container is improved by means of an adsorber thermally connected to a cooling apparatus. The cooling of the adsorber occurs preferably by means of evaporated cooling medium from the superconducting bearing.

Abstract: In a method for manufacturing metallic components by means of generative production, a layer of metal powder is selectively melted or sintered by being exposed to an energy beam in an evacuated radiation chamber. When the radiation chamber is subsequently flooded with a cooling gas, the melted or sintered part solidifies to form a solid contour. Instead of the previously common practice of using helium, which is expensive and not readily available, as the cooling gas, it is proposed according to the invention to use a gas that contains hydrogen. Hydrogen has a higher thermal conductivity than helium and does not impair the surface of the workpiece, or only to a negligible extent.

Abstract: 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.

Abstract: The disclosure relates to a device for improving a vacuum in the housing of a machine, in particular a centrifugal-mass energy store, comprising a rotor, for example a shaft having a centrifugal mass arranged thereon, which rotor is supported on at least one superconducting bearing in a contactless manner and is arranged in a vacuum container. In order to maintain the operating state of the superconducting bearing, the superconducting bearing is thermally connected to a cold source cooled by a cryogenic medium. According to the invention, the vacuum in the vacuum container is improved by means of an adsorber thermally connected to a cooling apparatus. The cooling of the adsorber occurs preferably by means of evaporated cooling medium from the superconducting bearing.

Abstract: 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.

Abstract: In a process for chlorine-alkali electrolysis, use is made of an oxygen depletion cathode. The process is run with a high excess of oxygen. The oxygen needed for this is provided for a device of the gas separation, for example a VPSA plant or an air fractionation plant. The large quantities of oxygen produced lead to considerable costs of the process. According to the invention, the oxygen-rich atmosphere remaining after passing through the process is fed back into the device for gas separation as input gas. The device the gas separation is therefore operated with an oxygen-rich input gas and therefore produces a larger quantity of oxygen-rich gas, which in turn is fed to the oxygen depletion cathode. As a result of the circulation of the gas, the economy of the overall process is increased considerably.

Abstract: In a process for chlorine-alkali electrolysis, use is made of an oxygen depletion cathode. The process is run with a high excess of oxygen. The oxygen needed for this is provided for a device of the gas separation, for example a VPSA plant or an air fractionation plant. The large quantities of oxygen produced lead to considerable costs of the process. According to the invention, the oxygen-rich atmosphere remaining after passing through the process is fed back into the device for gas separation as input gas. The device the gas separation is therefore operated with an oxygen-rich input gas and therefore produces a larger quantity of oxygen-rich gas, which in turn is fed to the oxygen depletion cathode. As a result of the circulation of the gas, the economy of the overall process is increased considerably.