Abstract: An integral high pressure rapid quenching vacuum furnace utilizing an electrical isolation transformer in the blower motor power control system in order to isolate the motor windings, reduce the possibility of gas ionization and eliminate ground faults, particularly when quenching in argon gas, is described. In order to achieve the desired mechanical properties of certain metal alloys being quenched using argon gas as a quenching medium in the high pressure gas vacuum furnace chamber, a 600 HP—460 Volt motor is required. A 460 Volt primary—460 Volt secondary [delta-delta] isolation transformer, having input and output windings separated by an electrostatic shield connected to ground is placed between the power source and the gas blower motor in the quenching chamber filled with argon gas. The 460 Volt power source is connected to a variable frequency drive (VFD) and the VFD is connected to the primary transformer winding. The secondary transformer winding connects 460 Volts to the blower motor windings.

Abstract: A quenching apparatus capable of quickly reversing a flow of cooling gas flowing in a chamber. The quenching apparatus includes: a chamber provided with a gas inlet and a gas outlet and having an object charged therein; a pair of flow generating means disposed on both sides of the chamber and generating a flow of gas in the chamber; and a flow direction reversing means disposed in the chamber and reversing a flow direction of gas to make the gas flow in any one of a first flow direction in which the gas flows from top to bottom of the object and a second flow direction in which the gas flows from the bottom to the top of the object.

Abstract: A heat treatment device includes: a heat treatment chamber which accommodates an object to be treated; a cooling gas supply unit which supplies a cooling gas into the heat treatment chamber; a cooling gas circulation unit which circulates the cooling gas in the heat treatment chamber; and a gas purge unit which gas-purges, with an inert gas, a portion in which there is a possibility of mixing of the cooling gas supplied into the heat treatment chamber and an oxygen gas, in which the cooling gas supply unit supplies a hydrogen gas into the heat treatment chamber as the cooling gas.

Abstract: A device for measuring distribution of thermal field in a crucible comprises a crucible comprising an upper lid, a body, a growth chamber and a material source zone; a thermally insulating material disposed outside the crucible; a movable heating component for heating the crucible; a plurality of thermocouples enclosed by insulating, high temperature resistant material and disposed in the crucible after being inserted into a plurality of holes on the upper lid to measure distribution of thermal field in the crucible. The thermocouples enclosed by insulating, high temperature resistant material are effective in measuring and adjusting temperature distribution in the crucible to achieve optimal temperature distribution for crystal growth in the crucible.

Abstract: A facility for continuously manufacturing a galvanized steel sheet includes a continuous annealing furnace, a snout, and a galvanization bath. The furnace is divided into a heating zone, a soaking zone, and a cooling zone. The bath is directly connected to the furnace through the snout. The facility has a dewpoint meter and a spray port and a suction port for a furnace gas that are provided in at least one of the zones, gas cyclic paths which connect the spray port and the suction port to a refiner, and a dewpoint meter and a humidification device that are provided in the snout. The gas cyclic paths are separately formed for the respective connected zones. The refiner functions so that a measured value of the dewpoint meter is equal to a target dewpoint, and the humidification device functions so that a measured value of the dewpoint meter in the snout is equal to a target dewpoint for the snout.

Abstract: The invention relates to a method and device for thermally treating workpieces, the device including a cooling chamber and two or more carburizing or heating chambers in which the workpieces are heated to a temperature of 950 to 1200° C. by means of radiation, such as direct heat radiation from a heating device.

Abstract: The vacuum heat treatment device includes: a guide plate used to guide a cooling medium supplied by a cooling unit, into a heat-insulating container through one of at least two openings of the heat-insulating container in a state where the two openings of the heat-insulating container are opened; and a movement mechanism used to move the guide plate so that at least part of the guide plate is inserted into a movement area of a cover portion in a state where the two openings of the heat-insulating container are opened and so that the guide plate is retracted from the movement area of the cover portion before the cover portion is moved in order to close the two openings of the heat-insulating container.

Abstract: A method of carburizing ferrous metal parts that includes the steps of providing a furnace for heating the metal parts and a process chamber, purging the air atmosphere from the process chamber and heating said process chamber to a temperature of at least 1100° F., feeding a gas to the process chamber and a source of air at a constant flow rate to the process chamber, boosting the process chamber by feeding an enriching gas to the process chamber to create a carbon potential of at least 0.5%, and more preferably of at least 1.4%, cleaning the process chamber by decreasing the flow of enriching gas to the process chamber to create a carbon potential of less than about 0.25%, repeating the boosting step after performing said cleaning step, and repeating the cleaning step after performing said boosting step.

Abstract: The invention relates to a method and device for thermally treating workpieces, the device including a cooling chamber and two or more carburizing chambers in which the work pieces are heated to a temperature of 950 to 1200° C. by means of direct heat radiation from a heating device.

Abstract: A charging frame for accommodating a batch of parts to be quenched, e.g., metal workpieces, has a circumferentially closed peripheral wall which surrounds the batch and thereby forms a flow channel which prevents bypass flows. The charging frame is a part of a quenching device.

Abstract: A rotating vacuum heat treatment equipment, applicable for heat treatment of rare earth permanent magnetic devices, hydrogen pulverization of rare earth permanent magnetic alloy, and heat treatment of mechanical electronic components, mainly comprises: a vacuum unit, a gas cooling device, and a vacuum furnace, wherein an insulating layer is provided in the vacuum furnace, a heater is provided in the insulating layer, a rotating cylinder is provided in the heater, a nozzle, connected with pipelines of the gas cooling device, is provided on the insulating layer, and cooled gas is sprayed to the rotating cylinder via the nozzle.

Abstract: A vacuum heat treatment method for NdFeB rare earth permanent magnetic devices and an equipment thereof are disclosed. A rotary vacuum heat treatment equipment is for processing the NdFeB rare earth permanent magnetic devices with a vacuum heat treatment and obviously improves magnetic performance of the NdFeB rare earth permanent magnetic device, especially coercivity, which facilitates reducing a usage of heavy rare earth elements and protecting rare earth resources. Thus the vacuum heat treatment method and the equipment thereof are able to manufacture high-performance rare earth permanent magnetic devices.

Abstract: The vacuum heat treatment device includes: a guide plate used to guide a cooling medium supplied by a cooling unit, into a heat-insulating container through one of at least two openings of the heat-insulating container in a state where the two openings of the heat-insulating container are opened; and a movement mechanism used to move the guide plate so that at least part of the guide plate is inserted into a movement area of a cover portion in a state where the two openings of the heat-insulating container are opened and so that the guide plate is retracted from the movement area of the cover portion before the cover portion is moved in order to close the two openings of the heat-insulating container.

Abstract: A heating section 20 having heating elements using carbon which generates heat when a high-frequency electric current is fed to a coil whose pitch can be adjusted as desired is arranged in a heating chamber 10. A cooling chamber 80 configured to cool metal is disposed below the heating chamber 10 in communication with the heating chamber 10 via a connection section 60. A water-cooled vertically movable shaft 90 which is capable of supporting the metal to be heat-treated and entering the heating chamber 10 is disposed so as to penetrate through the bottom portion of the cooling chamber 80. A gas introducing pipe 81 configured to introduce gas for cooling heated metal to be heat-treated supported by the water-cooled vertically movable shaft 90 and moved from the heating chamber 10 to the cooling chamber 80 is disposed in the cooling chamber 80.

Abstract: An alloy flake production apparatus (1) includes a crystallinity control device (2) for controlling an alloy crystal structure of fed alloy flakes to a desired state, a cooling device (3) for cooling the alloy flakes discharged from the crystallinity control device (2), and a chamber for keeping these devices under reduced pressure or under an inert gas atmosphere. The crystallinity control device (2) has a rotary heating drum (21) in a cylindrical shape for heating the fed alloy flakes, and a switching device (23) for switching between storage and discharge of the alloy flakes fed to an inner wall side of the heating drum (21), so that long-time heat treatment is uniformly applied to the alloy flakes immediately after being made by ingot crushing. The heating drum (21) preferably has a scooping blade plate (22) for scooping up alloy flakes fed to the inner wall side with its rotation.

Abstract: A method between a diffusion and a quenching process including normalizing by step cooling including alternating temperature lowering and temperature keeping treatment for a temperature history that satisfies a predetermined condition; after normalizing, maintaining the temperature of the whole workpiece so that the whole workpiece becomes the predetermined temperature, thereby producing fine crystal grains in the workpiece; then reheating the workpiece to raise its temperature to the second temperature. There is uniformity in temperature between the surface and the inside of a workpiece, and crystal grains are prevented from being coarse.

Abstract: An installation for the dry transformation of a material structure of semifinished products, particularly for dry bainitization, includes a quenching chamber and heating and/or cooling mechanism for setting the temperature prevailing on the inside of the quenching chamber, wherein the heating and/or cooling mechanism is developed as heating or cooling mechanism of a wall that borders on an inner chamber of the quenching chamber.

Abstract: A vacuum furnace for heat treating and rapid gas quenching insitu a work piece at pressures up to 20 Bar and high gas velocities. The furnace comprises a single chamber having an inner portion including a plurality of graphite heating elements and graphite insulation, an outer portion and an access door. Further included are movable radiation baffle doors. In their closed position hot gases heat treat the work piece. In their open position the hot gases escape through the opening created onto chevron-shaped baffles in the outer portion which reflect radiation heat energy back into the inner portion and diffuse only convective heat energy into a heat exchanger and a variable speed drive recirculating fan. The recirculating fan directs the cooling gases through cooling nozzles onto the work piece to quench it to a pre-programmed temperature.

Abstract: Systems and methods for hydrogen out gas of a porous metal scaffold are disclosed. A method can comprise heating a porous metal scaffold for a period of time sufficient to remove at least a portion of a hydrogen concentration from the scaffold, subjecting the porous metal scaffold to a vacuum while heating it, flowing an inert gas through or around the porous metal scaffold while heating it, and enhancing a mechanical property of the porous metal scaffold. Heating of the porous metal scaffold can include maintaining a temperature of the scaffold between 1035° C. and 1065° C., inclusive. A system can comprise a reaction chamber, a heater, a gas feed, and a vacuum apparatus. The heater can be configured to heat the reaction chamber and the porous metal scaffold, while the gas feed and the vacuum apparatus respectively flow inert gas and subject the porous metal scaffold to a vacuum.

Abstract: A vacuum carburization processing method includes a preparatory heating step of increasing the temperature of a workpiece in a heating chamber to a first temperature, a carburizing step of carburizing the workpiece by supplying carburizing gas into the heating chamber from a state where the pressure inside the heating chamber is reduced to an extremely low pressure, a diffusing step of terminating the supply of the carburizing gas and making carbon diffuse from a surface of the workpiece into its internal part, and a quenching step of abruptly cooling the temperature of the workpiece from a state where the temperature of the workpiece is at a second temperature; and also includes, between the diffusing step and the quenching step, a normalizing step of reducing the temperature of the workpiece so that the temperature history of the workpiece from the first temperature to a predetermined temperature satisfies predetermined conditions, a post-normalization maintaining step, performed after the normalizing step,

Abstract: Embodiments of methods for vacuum heat treating refractory metal articles (e.g., implantable medical devices), and heat treating apparatuses for use in such methods are disclosed. Heat treating refractory metal articles under high vacuum (e.g., 10?6 Torr) may improve strength and ductility and remove material contaminants (e.g., oxygen or hydrogen) that may be absorbed during manufacturing processes. Heat treating methods include disposing a refractory metal article in a heat treating apparatus, drawing a vacuum therein, and moving the article to a heated zone in the furnace using a drive system that permits movement of the article while the vacuum is maintained in the apparatus. A heat treating apparatus may include an elongate furnace tube that may be sealed and placed under vacuum, a heating element disposed around at least a portion of the tube, and a drive system configured for moving articles disposed inside the furnace tube while under vacuum.

Abstract: Provided is an annealing apparatus, which is free from a problem of reduced light energy efficiency resulted by the reduction of light emission amount due to a heat generation and capable of maintaining stable performance. The apparatus includes: a processing chamber 1 for accommodating a wafer W; heating sources 17a and 17b including LEDs 33 and facing the surface of the wafer W to irradiate light on the wafer W; light-transmitting members 18a and 18b arranged in alignment with the heating sources 17a and 17b to transmit the light emitted from the LEDs 33; cooling members 4a and 4b supporting the light-transmitting members 18a and 18b at opposite side to the processing chamber 1 to make direct contact with the heating sources 17a and 17b and made of a material of high thermal conductivity; and a cooling mechanism for cooling the cooling members 4a and 4b with a coolant.

Abstract: A heating section 20 having heating elements using carbon which generates heat when a high-frequency electric current is fed to a coil whose pitch can be adjusted as desired is arranged in a heating chamber 10. A cooling chamber 80 configured to cool metal to be heat-treated, which has been heated by the heating elements, is disposed below the heating chamber 10 in communication with the heating chamber 10 via a connection section 60. A water-cooled vertically movable shaft 90 which is capable of supporting the metal to be heat-treated and entering the heating chamber 10 is disposed so as to penetrate through the bottom portion of the cooling chamber 80.

Abstract: A method and a device for recovering hydrogen pulverized powder of a raw-material alloy for rare-earth magnets capable of lowering a possibility that hydrogen pulverized powder after hydrogen was pulverized remains in a recovery chamber and capable of enhancing magnetic properties by reducing an amount of oxygen of an obtained rare-earth magnet, a processing container 50 is carried into a recovery chamber 40 from a processing chamber through a carry-in port after inert gas was introduced into the recovery chamber 40 by inert gas introducing means 12, the raw-material alloy for rare-earth magnets in the processing container 50 is discharged into the recovery chamber 40 after the pressure in the recovery chamber 40 was reduced by evacuating means 33 and thereafter, inert gas is introduced into the recovery chamber 40 by inert gas introducing means 12, and the raw-material alloy for rare-earth magnets is recovered into the recovery container 50 from an discharge port 40a after a pressure in the recovery chamber

Abstract: There are provided a method, between a diffusion process and a quenching process, a normalizing process of performing step cooling in which a temperature lowering treatment and a temperature keeping treatment are alternately repeated plural times so that a temperature history from the first temperature to a predetermined temperature satisfies a predetermined condition; an after-normalizing maintaining process of maintaining the temperature of the whole workpiece for a predetermined time after the normalizing process so that the whole workpiece becomes the predetermined temperature, thereby producing fine crystal grains in the workpiece; and a reheating process of raising the temperature of the workpiece to the second temperature, after the after-normalizing keeping process.

Abstract: A heat treating furnace is disclosed for nitride case hardening and gas cooling a stationary workload in the same furnace which is comprised of a single chamber and an access door. The chamber is segregated into an outer portion and an inner portion, with the inner portion being adapted to receive the workload to be nitride case hardened through the access door. The inner portion is surrounded by graphite insulation to retain the gas used to nitride case harden the workload. The inner portion further includes a plurality of graphite resistance heating elements and a plurality of graphite plates juxtaposed in near proximity to the graphite resistance heating elements forming a conduit or plenum between them. The inner portion further includes a fan assembly including a graphite radial fan wheel adapted to circulate the nitriding gas within the inner portion and through the conduit to provide uniform nitride case hardening of the workload.

Abstract: A system for heat treating an alloy steel component includes a first enclosure and a second enclosure opposed to the first enclosure. The first and second enclosures define a chamber around only a portion of the alloy steel component. The system further includes a heating element in the chamber to heat the portion of the alloy steel component. A method for heat treating an alloy steel component includes placing a first enclosure against a first side of the alloy steel component and placing a second enclosure against a second side of the alloy steel component. The method further includes creating a substantially airtight chamber around only a portion of the alloy steel component between the first and second enclosures and heating the portion of the alloy steel component inside the substantially airtight chamber.

Abstract: A method and measurement system for the control of an active charge surface in a low pressure carburizing process can avoid formation of by-products and achieve regular carburized layers. This can be achieved through sampling of outlet gas at a specified time and comparison with experimentally set model characteristics.

Abstract: A metal powder production system includes a vacuum chamber having a vacuum chamber interior, a stock feed mechanism communicating with the vacuum chamber interior, a radiation source provided in the vacuum chamber interior, a cooling chamber having a cooling chamber interior communicating with the vacuum chamber interior and a container communicating with the cooling chamber interior. A metal powder production method is also disclosed.

Abstract: A double-chamber type heat-treating furnace comprises a hermetically closable cooling furnace, a hermetically closable heating furnace, and a transfer unit. The transfer unit has free rollers disposed within the heating and cooling chambers and for supporting the object at only both ends in a direction of width thereof, a push-pull member moving while being engaged with the object to push or pull the object, and a drive unit provided at a position adjacent to the heating chamber on a side opposite to a side on which the cooling chamber is disposed and driving the push-pull device.

Abstract: A refining apparatus for scrap silicon using an electron beam which is suitable for recycling of scrap silicon which is formed during the manufacture of silicon products such as silicon wafers includes a vacuum chamber, a crucible installed within the vacuum chamber, a hearth which is installed next to the crucible within the vacuum chamber and which receives granular scrap silicon and which melts granular silicon by irradiation with an electron beam and which supplies molten silicon to the crucible, and a raw material supply apparatus which is installed within the vacuum chamber and which stores a prescribed amount of granular scrap silicon and supplies the stored granular scrap silicon via a chute.

Abstract: Provided is an annealing apparatus, which is free from a problem of reduced light energy efficiency resulted by the reduction of light emission amount due to a heat generation and capable of maintaining stable performance. The apparatus includes: a processing chamber 1 for accommodating a wafer W; heating sources 17a and 17b including LEDs 33 and facing the surface of the wafer W to irradiate light on the wafer W; light-transmitting members 18a and 18b arranged in alignment with the heating sources 17a and 17b to transmit the light emitted from the LEDs 33; cooling members 4a and 4b supporting the light-transmitting members 18a and 18b at opposite side to the processing chamber 1 to make direct contact with the heating sources 17a and 17b and made of a material of high thermal conductivity; and a cooling mechanism for cooling the cooling members 4a and 4b with a coolant.

Abstract: The invention relates to a gas quenching method of the type that makes use of (i) a quenching cell (V1) which is intended to receive objects to be quenched with a quenching gas and (ii) a buffer capacity (V2) which is designed to contain the quenching gas.

Abstract: A vacuum furnace adapted to cool a load. The vacuum furnace has one or more means for cooling a fluid and a muffle substantially comprised of carbon fiber composite and substantially containing the load. The fluid flows in a substantially unidirectional flow substantially within the muffle.

Abstract: Versatile vacuum furnace (also having high internal pressure capability) designed for facilitating directed gas flow has a treating chamber including a long, low profile work zone configuration, and powerful gas recirculation equipment with unique structure supporting gas flow patterns that facilitate high velocity gas flow into and through the chamber. The furnace can be used for single or multiple step metal treatment processes. An entire multi step process, for example, carburizing, including gas quenching, is accomplished relatively quickly in a single self-contained chamber of the furnace.

Abstract: In an improved annealing furnace for laminations having a purge vestibule and an oxidation section, atmosphere injection tubes with atmosphere injection jets are provided in the oxidation section at a conveyor directly beneath trays conveying the laminations. Atmosphere extraction tubes are also provided along with a fan which draws atmosphere from the extraction tubes and provides a pressure output to the atmosphere injection tubes. The speed of the fan may be variable.

Abstract: The present invention includes a furnace, a plurality of pallets, a pusher device, and a pusher-puller device. The furnace includes a carburizing zone in which carburizing processing is performed upon workpieces loaded upon trays during the conveyance of these trays along a direction of conveyance, and a plurality of regions which are arranged successively along the direction of conveyance at the upstream side of the carburizing zone. Along with a tray upon which workpieces are loaded being mounted upon each one of the plurality of pallets, these pallets are movable along a linear conveyance direction, with the number of pallets being the same as the number of regions. The pusher device pushes the trays along the direction of conveyance. And the pusher-puller device, along with pushing the plurality of pallets all together forward along the direction of conveyance, also pulls one of the plurality of pallets backward into each of the plurality of regions.

Abstract: There are provided a method, between a diffusion process and a quenching process, a normalizing process of performing step cooling in which a temperature lowering treatment and a temperature keeping treatment are alternately repeated plural times so that a temperature history from the first temperature to a predetermined temperature satisfies a predetermined condition; an after-normalizing maintaining process of maintaining the temperature of the whole workpiece for a predetermined time after the normalizing process so that the whole workpiece becomes the predetermined temperature, thereby producing fine crystal grains in the workpiece; and a reheating process of raising the temperature of the workpiece to the second temperature, after the after-normalizing keeping process.

Abstract: A method and device for inhibiting contamination of a workpiece during the heating of a workpiece by a contaminant. The method includes placing the workpiece in a first container, and, in a first step, filling the first container with a protective gas. The first container is placed in a second container, and in a second step, the second container, and hence the first container contained therein, is evacuated to create a vacuum inside the first and second containers so that during the first and second steps the partial pressure is reduced for the contaminants in the first container before the workpiece is heated.

Abstract: A hydrogen closed-cycle hardening unit is disclosed that consisting of a vacuum oven with an internal quenching and circulation system, adjusted to operate under a pressure of 2 MPa, fitted with conduits and valves for feeding and discharging of quenching atmosphere. The oven, fitted with a hydrogen and/or nitrogen inlet line and an operating gas outlet line, is connected to two conduits, between the conduits' valves, and, through these conduits, to a unit of two containers. The first container, which is connected to an external hydrogen source, contains a metal alloy absorbing hydrogen as a high-pressure hydride, while second container contains a metal alloy absorbing hydrogen as a low-pressure hydride. Both containers are connected by another conduit.

Abstract: The present invention provides a vacuum heat treating method, such as carburization, carbonitridation, high temperature carburization, high concentration carburization and the like, performed while supplying a mixed gas of ethylene gas and hydrogen gas under reduced pressures. The method includes: detecting a quantity of ethylene gas and that of hydrogen gas in a vacuum heat treating furnace (1); calculating an equivalent carbon concentration of atmosphere on the basis of the detected quantity of ethylene gas and that of hydrogen gas; and comparing the calculated value with a targeted value which is set on the basis of a material specification and required heat treatment performance of an object to be treated (a workpiece), to control quantities of ethylene gas and hydrogen gas supplied into the vacuum heat treating furnace (1) on the basis of a difference between the calculated value and the targeted value. A heat treatment quality required for the workpiece can be obtained with accuracy and reproducibility.

Abstract: A vacuum carburization processing method includes a preparatory heating step of increasing the temperature of a workpiece in a heating chamber to a first temperature, a carburizing step of carburizing the workpiece by supplying carburizing gas into the heating chamber from a state where the pressure inside the heating chamber is reduced to an extremely low pressure, a diffusing step of terminating the supply of the carburizing gas and making carbon diffuse from a surface of the workpiece into its internal part, and a quenching step of abruptly cooling the temperature of the workpiece from a state where the temperature of the workpiece is at a second temperature; and also includes, between the diffusing step and the quenching step, a normalizing step of reducing the temperature of the workpiece so that the temperature history of the workpiece from the first temperature to a predetermined temperature satisfies predetermined conditions, a post-normalization maintaining step, performed after the normalizing step,

Abstract: The invention provides a carburization treatment method in which a carburization treatment is conducted simultaneously with an operation of supplying a hydrocarbon gas and an oxidative gas into a furnace kept under a reduced pressure. Preferably, the internal pressure within the furnace is kept at 0.1 to 101 kPa, the hydrocarbon gas is one, two or more than two kinds of gases selected from the group consisting of C3H8, C3H6, C4H10, C2H2, C2H4, C2H6 and CH4, while the oxidative gas is an air, an O2 gas, or CO2 gas.

Abstract: Vacuum carburizing of ferrous workpieces is performed at low pressure in a vacuum furnace using an unsaturated aromatic such as benzene as the carburizing medium. The unsaturated aromatic is gas phase hydrogenated into naphthenes, such as cyclohexane, which is metered into the furnace chamber proper and functions as the carburizing gas. The furnace is constructed to be generally transparent to the naphthenes so that cracking tends to occur at the workpiece which functions as a catalyst to minimize carbon deposits. The unsaturated aromatic is supplied in liquid form to fuel injectors which inject the liquid aromatic as a vapor at duty cycles and firing orders to produce a uniform dispersion of the hydrocarbon gas about the work resulting in uniform carburizing of the workpieces. An in-situ methane infrared sensor controls the process.

Abstract: A method and an apparatus for the thermal treatment of metallic workpieces with which gas quenching can be obtained that is low in distortion, even for workpieces with an undulating shape or workpieces that are projectingly stackable are provided. In accordance with the method, after being heated the workpieces are cooled in a quenching chamber with a quenching gas, whereby the quenching gas is intentionally caused to flow around the workpieces by means of guide channels that have a closed lateral surface and that enclose the workpieces along the direction of flow of the quenching gas. The apparatus comprises a quenching chamber in which the workpieces can be cooled with a quenching gas, and wherein guide channels are provided to ensure that the quenching gas flows around the workpieces, the guide channels having a closed lateral surface and enclosing the workpieces along the direction of flow of the quenching gas.

Abstract: A check valve assembly for the forced gas cooling system of a vacuum heat treating furnace is disclosed. The check valve assembly includes a check valve for installation on the exterior of a hot zone wall in a vacuum heat treating furnace. The check valve includes a valve body forming an inlet, an outlet, and a channel extending longitudinally through the valve body. The valve body has an inner wall that forms a recess near the inlet. The channel contains a flap pivotally supported on a shaft that extends through the recess. The flap pivots in and out of the channel to permit a cooling gas to flow through the valve body in one direction while substantially preventing the flow of gas through the valve body in the opposite direction. The flap is operable between a closed position in which the flap extends into the channel to obstruct the channel, and an open position in which the flap is pivoted out of the channel and into the recess.

Abstract: A continuous vacuum carburizing furnace of the invention includes: a heating chamber for heating a workpiece under a atmospheric pressure; a first conditioning chamber in which the pressure is reduced from the atmospheric pressure after the receipt of the workpiece from the heating chamber; a carburizing/diffusing chamber receiving plural workpieces from the first conditioning chamber and conducting plural cycles of carburizing and diffusing processes under the reduced pressure; a second conditioning chamber in which the reduced pressure is returned to the atmospheric pressure after the receipt of the workpiece treated in the carburizing/diffusing chamber; and a cooling chamber for cooling the workpiece introduced from the second conditioning chamber under the atmospheric pressure, the furnace further comprising a door member disposed between a respective adjoining pair of the above chambers, the door member opened/closed only when the workpiece is transported from one chamber to another.

Abstract: In an apparatus for the treatment of metallic workpieces (4) with cooling gas, having a cylindrical housing (3) with an opening at the end face for introducing and removing the workpieces (4), two support plates (6, 7) extending in parallel planes vertically in the housing (3) and two air-guiding plates (14, 15) are provided, the workpiece batch (4) being held between the support plates (6, 7), and the air-guiding plates (14, 15) each forming, with the adjacent support plates (6, 7) and with the respectively adjacent inner wall of the housing, shafts (16, 17 and 26, 27, respectively) through which the cooling gas conveyed by blowers held on the housing (3) flows, controlled by reversing flaps (18, 19, 20, 21) arranged at the upper and lower ends of the air-guiding plates (14, 15).

Abstract: A furnace for heat treating of metal parts includes a hot zone enclosure defining a hot zone therein. The hot zone enclosure has a side wall, a first end wall, and a second end wall. The side wall has slots formed therethrough and along the length thereof. The heat treating furnace also includes a system for injecting a cooling gas into the hot zone through the hot zone enclosure. The heat treating furnace further includes a damper arrangement for directing the cooling gas over a selected portion or portions of the workpiece load and through one or more of the slots. In one embodiment of the invention, all actuated components in the furnace are located outside of the hot zone to minimize damage to moving parts that are caused by exposure to extreme heat.

Abstract: The present invention provides a vacuum heat treating method, such as carburization, carbonitridation, high temperature carburization, high concentration carburization and the like, performed while supplying a mixed gas of ethylene gas and hydrogen gas under reduced pressures. The method includes: detecting a quantity of ethylene gas and that of hydrogen gas in a vacuum heat treating furnace (1); calculating an equivalent carbon concentration of atmosphere on the basis of the detected quantity of ethylene gas and that of hydrogen gas; and comparing the calculated value with a targeted value which is set on the basis of a material specification and required heat treatment performance of an object to be treated (a workpiece), to control quantities of ethylene gas and hydrogen gas supplied into the vacuum heat treating furnace (1) on the basis of a difference between the calculated value and the targeted value. A heat treatment quality required for the workpiece can be obtained with accuracy and reproducibility.