Abstract: An apparatus for heating a workpiece at elevated temperatures both under vacuum and under superatmospheric pressures comprises a vacuum pressure vessel comprising a cylindrical pressure shell having an inner cylindrical sealing face near the upper edge thereof and a cover at one axial end and a bottom plug at the other axial end. Both are arranged to be placed within a reaction frame bearing thereupon. A furnace within the shell has an insulating hood for protecting the shell from the heated workspace. A vacuum manifold is mounted to the top edge of the cylindrical shell and is sealed thereto. The manifold has a cylindrical interior through which the cover passes and an inner cylindrical sealing face at the upper end thereof. Mechanically powered means are provided for raising and lowering the cover and placing it in a first or a second position.

Abstract: The high pressure furnace comprises a cylindrical pressure vessel with fr and rear pressure closures. An electrical heating element is supported within the interior of the pressure furnace. The front closure supports a relatively thin-walled inner container opening only to an aperture in the front closure. A small closure plugs the aperture. A reaction frame secures the various closures. Blanket gases are introduced into the furnace chamber and process gases into the process chamber defined by the interior of the inner container. Means are provided for minimizing the pressure difference across the inner container to enable it to maintain its original shape.

Abstract: An apparatus or system for cooling the interior of an autoclave furnace vessel after it has been pressurized with a gas and heated. The system comprises a heat conducting conduit opening at one end to the furnace interior and at the other end to a shut-off valve exterior to the vessel. Intermediate the two ends of the conduit is a coil portion comprising a heat exchanger positioned at a location in the furnace where hot vessel gases may be forced through or past the coil. Furnace gases are forced into the conduit and therefore through the coiled portion where they are heated prior to being exhausted. According to a preferred embodiment of this invention, there is a Joule-Thomson valve before the coiled portion of the conduit to reduce the temperature of the exhausting gases prior to arriving at the coiled portion.

Abstract: Apparatus for treating a workpiece at elevated temperatures both under vacuum and under superatmospheric pressures to provide for vacuum sintering and hot isostatic pressing in the same apparatus. The apparatus according to this invention comprises a vacuum-pressure vessel and a furnace within the vessel having a pedestal upon which the hearth rests extending up into the furnace. A first electrical heating means spaced about the pedestal is entirely below the hearth. At least one second electrical heating means is spaced about the workspace above the hearth. Means for separately controlling the first and second electrical heating elements are provided. The furnace can provide substantial uniform temperature distribution to the workpiece resting upon the hearth when the vessel is evacuated by direct radiation from the electrical heating means above the hearth. When the vessel is pressurized, uniform temperature distribution is maintained by convection from the electrical heating means below the hearth.

Abstract: This invention relates to an electric furnace and, in particular, an electric furnace having graphite rod heating elements electrically connected into more than one series circuit. In this way, the heating elements can be arranged to provide individually controllable heating zones.The heating elements are supported by hollow graphite cylinders and flanges extending radially inward from the hollow cylinders. The rod heating elements extend upwardly from the flanges being held near the lower ends thereof.

Abstract: An apparatus or system for cooling the interior of an autoclave furnace vessel after it has been pressurized with a gas and heated. The system comprises a heat conducting conduit opening at one end to the furnace interior and at the other end to a shut-off valve exterior to the vessel. Intermediate the two ends of the conduit is a coil portion comprising a heat exchanger positioned at a location in the furnace where hot vessel gases may be forced through or past the coil. Furnace gases are forced into the conduit and therefore through the coiled portion where they are heated prior to being exhausted. According to a preferred embodiment of this invention, there is a Joule-Thomson valve before the coiled portion of the conduit to reduce the temperature of the exhausting gases prior to arriving at the coiled portion.

Abstract: An apparatus for treating a workpiece at elevated temperatures and pressures comprising an elongate cylindrical pressure vessel. Within the pressure vessel a hearth sits upon a pedestal. Heating elements are circumferentially spaced about the hearth. A heat insulating hood separates the workpiece from the pressure vessel. A cylindrical reflecting shield separates the heating element from the insulating hood.

Abstract: The high pressure furnace comprises a cylindrical pressure vessel with front and rear pressure closures. An electrical heating element is supported within the interior of the pressure furnace. The front closure supports a relatively thin-walled inner container opening only to an aperture in the front closure. A small closure plugs the aperture. A reaction frame secures the various closures. Blanket gases are introduced into the furnace chamber and process gases into the process chamber defined by the interior of the inner container. Means are provided for minimizing the pressure difference across the inner container to enable it to maintain its original shape.

Abstract: An apparatus for treating a workpiece at elevated temperatures and pressures comprising an elongate cylindrical pressure vessel. Within the pressure vessel a hearth sits upon a pedestal. Surrounding the pedestal and the workspace immediately thereabove is an insulated furnace enclosure. A cavity near the base of the pedestal defines an impeller chamber. An impeller is positioned in the chamber and has a downwardly extending drive shaft. The impeller circulates the pressurized atmosphere. A remotely actuated gate directs the circulating atmosphere to either circulate totally within the furnace enclosure or partially within the furnace enclosure and partially along the interior wall of the pressure vessel.

Abstract: An apparatus for treating a workpiece at elevated temperatures and pressures comprising an elongate cylindrical pressure vessel. Within the pressure vessel a hearth sits upon a pedestal. A cavity near the base of the pedestal defines an impeller chamber. An impeller is positioned in the chamber and has a downwardly extending drive shaft which is magnetically driven from outside the pressure vessel.

Abstract: This invention relates to an electric furnace and, in particular an electric furnace having graphite rod heating elements electrically connected into more than one series circuit. In this way, the heating elements can be arranged to provide individually controllable heating zones.

Abstract: A work piece in a hot gas isostatic bonding furnace is cooled by increasing convection within the furnace prior to depressurizing. The convection may be wholly due to thermal gradients or may be supplemented by a compressor. The cooling jacket for the furnace walls may supply the entire cooling or may be supplemental heat exchanger. The quenching takes place within the furnace without changing the atmosphere.