Abstract: A melting furnace includes a melting portion to which a metal material is supplied; a burner for melting the metal material in the melting portion; a heating portion that receives the molten material from the melting portion; a temperature regulating portion that receives the molten material from the heating portion; a separator that separates the heating portion and the temperature regulating portion, wherein the lower portion of the separator is immersed in the molten material to form, below the separator, an inlet; an immersion heater wherein at least part of the immersion heater is immersed in the molten material in the temperature regulating portion; and a gas introduction path that is formed in the separator, and that introduces combustion gas from the burner into a space above the molten material in the temperature regulating portion; wherein the burner is controlled so that the combustion gas has an oxygen concentration of 5% or less.

Abstract: An apparatus and method for debindering a cellular ceramic green body. The apparatus includes a flow modulation member to selectively restrict circulation of a heated oxygen-containing atmosphere through a top of a cellular core section of the green body. The method includes heating the green body in a circulating oxygen-containing atmosphere while selectively restricting circulation of the atmosphere through the top of the cellular core section of the green body.

Abstract: An energy efficient metal melter has a portion of melting energy supplied to it by a combustion process for heating a melter charge to a temperature where the melter charge can no longer maintain its shape. A portion of melting energy is also supplied by an electrical process for adding remaining transformational and sensible heat. The combustion process preferably uses a hydrocarbon fuel energy source selected from a distillate compound, gas compound or both and the electrical energy comes from a source selected from an external power grid, a generator and combinations thereof.

Abstract: A heat treatment container for a vacuum heat treatment apparatus according to an exemplary embodiment includes a bottom portion and a sidewall, and a support protruding inward.

Abstract: A lightweight, compact, easy-to-use, portable furnace used for quickly assaying crushed ore samples in the field and used by prospectors, miners, and geologists. The portable furnace can also be used for smelting precious metals and refining and recycling different metals. The furnace includes a metal stand having a stand base with a first end portion with a dish opening therein and a second end portion with an upwardly folded heat shield. The heat shield includes a nozzle groove therein for receiving a gas nozzle. The gas nozzle is part of a gas blow torch having a handle and a gas tank. The stand base also includes first and second sides folded downwardly for holding the metal stand above a flat surface. A bottom of a scorifying dish is received in the dish opening. A cupel is received inside the open top of the scorifying dish. The cupel is adapted for receiving a crushed ore sample therein to be assayed. A dish lid is received on top of the scorifying dish.

Abstract: The device for melting and purifying of a silicon feedstock comprises a crucible arranged inside a sealed chamber. A thermal gradient can be applied to the crucible by an arranged heat exchanger and a heating device. The device likewise comprises a device for reducing the pressure inside the chamber to a value lower than 10?2 mbar and a device for stirring the silicon in the crucible. The silicon feedstock successively undergoes degassing and pre-heating to atmospheric temperature, and then melting and low pressure, high temperature purification. Once the low-pressure purification step has been completed, directed crystallization is carried out.

Abstract: A bead furnace has a furnace with a furnace chamber 4 and opening 6. A closure assembly 20 is provided on closure assembly 22. The closure assembly has a blank closure element 26 and an active closure element 32 on different sides of the closure assembly, each matching the opening 6. A crucible holder 44 with a detent for holding a crucible and a mold holder 60 for holding a mold are provided on the active face. The closure assembly moves between two states, a load state with the blank closure element 26 in the furnace opening and an operation state with the active closure element 32 in the furnace opening with the crucible and mold in the furnace. The closure assembly can agitate the crucible contents and then tip the crucible to pour fused contents into the mold.

Abstract: The invention relates to an apparatus and process for the production of polycrystalline silicon for photovoltaic applications. The apparatus is characterized in that it comprises of multiple chambers, preferably three, arranged longitudinally one after the other and equipped with: gas immission and extraction means; means for guiding and moving the crucible containing the silicon-based material; insulation and temperature control means; heating means; air-tightness means for each chamber. One of said chambers constitutes the furnace of the apparatus and comprises an area in which the smelting of the material contained in the crucible is carried out, said furnace being equipped with heating means and bearing a heat-stable pedestal, suitable for moving the crucible vertically and thus for introducing it into, or extracting it from the smelting area, respectively.

Abstract: Pottery wares are fired in a saggar in an electric kiln, whereby effects such as reduction firing and soda firing may be obtained.

Abstract: An evaporator for vaporizing an organic material to be deposited on a flexible substrate where the evaporator includes an evaporation tube having a wall encompassing a cavity for vaporizing the organic material, at least one heating device arranged adjacent to the wall and being adapted to heat the evaporation tube, and at least one nozzle assembly protruding from the evaporation tube. The nozzle assembly further comprises a nozzle cover with an opening, and a shutter for selectively opening and closing the opening of the nozzle cover. The shutter is adapted to have in operation of the evaporation tube a temperature within a shutter temperature range of 140° C. such that the temperature of the nozzle cover is within the shutter temperature range.

Abstract: A method for forming polysilicon material for photovoltaic cells. A first silicon material characterized by a first purity level is provided. The first silicon material is subjected to a thermal process to transform the first silicon material to a molten state confined in a first spatial volume. The molten first silicon material is subjected to a directional cooling process provided in a second spatial volume for a predetermined period, removing thermal energy from a first region. A polycrystalline silicon material characterized by a second purity level and an average grain size greater than about 0.1 mm is formed from the molten first silicon material in a vicinity of the first region. One or more silicon wafers is formed from the polycrystalline silicon material. A polysilicon film material characterized by a grain size greater than about 0.1 mm is deposited overlying each of the silicon wafers.

Abstract: The present invention provides a crucible-type continuous melting furnace by which the melted amount of the material can be readily controlled. A crucible-type continuous melting furnace 1 includes a preheating tower 31 for storing the material to be melted (a), and an exhaust port 34 on the top thereof; a melting crucible furnace 11 disposed below the preheating tower 31 and having a melting crucible 71 to which the material to be melted (a) is supplied from the preheating tower 31; a heating burner 3 for heating the melting crucible 71; and a preheating burner 4 for preheating the material to be melted and disposed in a position that is higher than the heating burner 3; the melting crucible furnace 11 having an introduction portion for introducing a combustion gas from the heating burner 3 into the preheating tower 31; and the melting crucible 71 having a molten metal outlet 74 on the side wall for discharging the molten metal (b) obtained by melting the material (a).

Abstract: A kiln and method of firing a kiln are provided for use in connection with the firing of small-scale pottery firing. The kiln includes a kiln wall that defines a main kiln volume that is no larger than 60 cubic feet and is less than 10 cubic feet in one embodiment. The main kiln volume is structured to receive a pottery item for firing. The kiln further includes a combustion chamber that is thermally connected to the main kiln volume. A feeder automatically feeds solid fuel to the combustion chamber to reach and maintain at least a cone 10 temperature within the main kiln volume. In use, solid fuel is automatically provided to a combustion chamber at a controlled rate and is combined with combustion air in the combustion chamber. The solid fuel is combusted in the combustion chamber to warm a thermally-connected main kiln volume.

Abstract: Disclosed is a multilayer structured quartz glass crucible, for pulling up silicon single crystal, whose structure has at least three layers comprising: a translucent outer layer made of naturally occurring quartz glass and having a large number of pores, a translucent intermediate layer, made of synthetic quartz glass and having a large number of pores, and a transparent inner layer substantially free from pores and made of a synthetic quartz glass. Thermal convection within the silicon melt is suppressed by use of the quartz glass crucible, thereby preventing oscillation on the surface of the silicon melt. A method for producing the quartz glas crucible is also disclosed.

Abstract: An apparatus and process for producing charcoal in a kiln from hardwood. The kiln is constructed over an array of hardwood logs supported on a suitable platform. Fill material is used to form a surrounding jacket surrounding the hardwood, a sawdust layer is applied over the surrounding jacket, and an airtight layer of clay earth and sand is applied over the sawdust layer. An ignition access port is provided through the several layers to allow ignition and combustion of the hardwood, after which the access port is closed to prevent air from entering the interior of the kiln during burning of the hardwood. After a predetermined burning time, the kiln and its contents are allowed to cool, and the filler, clay earth, sand and any remaining debris are removed from the hardwood. The hardwood is then cooled a second time, and then cooled a third time by stifling the hardwood, such as in a cooling box capped with earth.

Abstract: A portable kiln has a set of wheels, a handle and a platform base. The wheels and the handle are attached on a first side of the kiln so that the kiln can be tilted and rolled on the wheels using the handle. The platform base provides a spaced distance between the wheels and the floor when the kiln is sitting upright in an operational position. The kiln may also include a metal outer shell wrapped about an oven portion. The outer shell has a shell sidewall radially spaced from the oven portion sidewall, which forms an annular air channel between the outer shell sidewall and the oven portion. The outer shell has a C-shaped cross-section and it has upper and lower vent openings for the air channel. A hinge assembly allows a lid of the kiln to rest in an open position.

Abstract: A method of forming a pyrolytic boron nitride (PBN) article and an article having layers of PBN separated by layers of PBN having a dopant of sufficient concentration to induce peeling, the steps of introducing vapors of ammonia and a gaseous boron halide in a suitable ratio into a heated furnace reactor to cause boron nitride to be deposited in layers on a substrate, with at least one gaseous dopant injected into furnace at controlled periodic interval(s) such that at least two selected layers of boron nitride are doped with said gaseous dopant(s) at a minimum average concentration of 2 atomic wt % at a depth ranging from 1000 to 2000 angstroms in each selected layer, and with the selected layers spaced apart about 0.1 micron to 100 microns apart.

Abstract: The furnace body uses a crucible as the innermost layer thereof to reduce wearing of furnace materials and achieve downsizing of the furnace body; the crucible is made into the form of a cartridge so as to fully facilitate replacement thereof; a mixture of a petroleum gas such as propane and butane and an oxygen gas or air is used mainly as a fuel, which is subjected to complete combustion to ensure complete combustion of the fuel, as well as, sufficient temperature control; and an arrangement is employed for contriving arrangement of the burner, the ash charge port, and other elements so as to improve heat efficiency, thus facilitating temperature control in the furnace, reducing wearing of the furnace body and facilitating repair of the furnace.

Abstract: A device for the melting of highly pure optical glasses and/or for the treatment of melts is provided. The device is intended for a subsequent refining or homogenization process making use of the skull technique. The device uses a number of coated metal tubes whose surface is free of glass-coloring ions.

Abstract: A more efficient combustion or oxidation device for the formation of nitrogen, phosphorus and/or sulfur oxides from a sample containing these elemental constituents is disclosed. The device uses multi-staged addition of an oxidizing agent to enhance oxidation and liberation of nitrogen, phosphorus and/or sulfur oxides for subsequent detection. The oxidation devices of the present invention allow for the injection of larger samples or, the introduction of a greater amount of sample per unit of time which results in a larger amount of analyte being delivered to the detector per unit of time, thereby improving detection limits and detection efficiency.

Abstract: A coal/coke sample is heated under controlled circumstances as a step in determining content of volatile matter. The sample is placed in a crucible having a lid and which is suspended by means of a crucible holder in a heating cavity of a furnace. The invention provides precisely, mechanically guiding the crucible holder and crucible into and out of the cavity to prevent inadvertent touching of the cavity wall by the crucible and thus also to prevent possible dislodging of the lid and spoiling of the sample. The crucible holder is secured to a lid of the furnace, and the furnace lid is guided along upwardly extending guide rods. Lifting and lowering of the lid may be manually. Instead, it may be hydraulically or pneumatically.

Abstract: A porous ceramic body having a ceramic framework is produced having a surface roughness of about 40 microns or less. The ceramic body has a plurality of pores where each pore is interconnected with at least one adjacent pore. The ceramic body is made from a powdered ceramic component and a pore-forming polymeric component such as polymeric beads. The ceramic component is alumina which can contain at least one other component selected from the group consisting of calcium oxide, silicon oxide, magnesium oxide, barium oxide, titanium dioxide, and zirconium dioxide. The pore-forming polymeric beads, such as polymethylmethacrylate beads, each having a particle size of 100 microns or less, are mixed with the ceramic powder. The powdered mixture is compressed under pressure and heated to form a porous ceramic body. A coating of an aqueous dispersion of a metal oxide can be applied to the surface of the ceramic body and heated to produce a smooth and durable coating.

Abstract: Refractory ceramics and composite materials consisting of nitrides, carbides, mixed carbides and oxides, oxycarbides, mixed nitrides and oxides, and oxynitrides of Group IVB metals Hf, Zr, and Ti, Group IIA metals Be, Mg, Ca, Sr, and Ba, and Group IIIB metals Sc, Y, and lanthanides La through Lu are used to form refractory articles, or as coatings for refractory articles. These materials and articles have high resistance to molten metals, molten salts, erosion, and high temperature corrosive environments, and can be engineered to have desirable thermal and electrical properties. The refractory materials encompass nitrides, carbides, reacted ternary and quaternary oxides, mixed carbides and oxides, oxycarbides, mixed nitrides and oxides, and oxynitrides and have the general chemical formula M.sub.x1 M'.sub.x2 M".sub.x3 N.sub.y C.sub.w O.sub.z where M is Hf, Zr, or Ti, M' is Be, Mg, Ca, Sr, or Ba, M" is Sc, Y, and lanthanides La through Lu, N is nitrogen, C is carbon, O is oxygen.

Abstract: A unibody, monolithic, one-piece negative draft crucible for a MBE effusion cell. The crucible maximizes capacity, uniformity and long term flux stability, and minimizes oval defects, depletion effects, and short term shutter-related flux transients. The invention also provides a method and mandrel apparatus for making a unibody containment structure, such as a crucible formed of PBN, having a negative draft, via chemical vapor deposition.

Abstract: In order to reduce concentrations of impurities in an inner layer of a quartz crucible for pulling a silicon single crystal which comprises an outer layer made of quartz glass and an inner layer formed on the inner surface of the outer layer, a migration-preventing layer is formed between the outer and inner layers, wherein the migration-preventing layer prevents migration of the impurities such as alkaline metals included in the natural quartz glass in the outer layer to the synthetic quartz glass in the inner layer.

Abstract: A jig used for heat treatment made from an SiC-coated silicon carbide material, wherein the SiC film is coated by the CVD method on a silicon carbide matrix in which silicon has been impregnated and wherein there are no pores with a diameter of 2 .mu.m or larger in the outer layer of the matrix within 200 .mu.m from the interface of the SiC film and the silicon carbide matrix when observed by a scanning electron microscope at a magnification of 400 times. The jig is manufactured by producing an SiC film on the surface of a silicon carbide matrix in which silicon has been impregnated by introducing a raw material compound for producing the SiC film and forming the SiC film at a temperature from 1000.degree. C. to 1290.degree. C. under a pressure from 500 to 760 Torr in a non-oxidative atmosphere. The jig exhibits superior resistance to high temperature heating cycles and excellent high thermal shock resistance required for heat treatment in semiconductor manufacturing.

Abstract: A unibody, monolithic, one-piece negative draft crucible for an MBE effusion source. The crucible maximizes capacity, uniformity and long term flux stability, and minimizes oval defects, depletion effects, and short term shutter-related flux transients. The invention also includes an effusion source employing such a crucible, as well as a method and mandrel apparatus for making a unibody containment structure, such as a crucible formed of PBN, having a negative draft, via chemical vapor deposition.

Abstract: A unibody, monolithic, one-piece negative draft crucible for a MBE effusion cell. The crucible maximizes capacity, uniformity and long term flux stability, and minimizes oval defects, depletion effects, and short term shutter-related flux transients. The invention also provides a method and mandrel apparatus for making a unibody containment structure, such as a crucible formed of PBN, having a negative draft, via chemical vapor deposition.

Abstract: This invention relates to an apparatus comprising:a) a article having a composition selected from the group consisting of graphite, carbon/carbon, carbon/graphite, and mixtures thereof, andb) a ceramic coating thereon, wherein the ceramic coating comprises a material selected from the group consisting of:i) a ceramic having an average thermal expansion coefficient of between 2 and 8.times.10.sup.-6 /.degree. C. between 22.degree. C. and 1200.degree. C. which is also phase stable in the temperature range of 22.degree. C. and 1450.degree. C., andii) alumina having at least 99% purity.

Abstract: A solid material delivery system for a furnace which melts the solid material has a delivery tube located at least partially within the furnace which is mounted by a rotor assembly for selective radial positioning in the furnace over a crucible in the furnace. The rotor assembly is constructed to compensate for thermal expansion and contraction caused by the furnace so that free movement of the delivery tube is achieved at all operating temperatures. The rotor assembly is also constructed to prevent jamming caused by particulate solid material in the rotor assembly. The delivery tube is formed so that flowable solid material will flow in a controlled fashion but without clogging to an outlet. The delivery tube and outlet are shaped to drop the material in a substantially columnar stream into the crucible.

Abstract: An exhaust system for use with a high temperature furnace used to perform oxidation and/or annealing operations of the type used in semiconductor fabrication. The exhaust system is designed to permit the furnace to be used with a controlled environment chamber surrounding the entry to the process chamber of the furnace. The exhaust system allows a relatively high velocity flow of exhaust gas from the process chamber through the exhaust system to occur when a positive pressure (e.g., annealing) operations are performed. Such high velocity flow prevents (a) backstreaming and (b) the accumulation of non-uniform concentrations of exhaust gases in the exhaust system, thereby permitting the accurate monitoring of the concentration of a selected gas in the exhaust system. Based on such monitoring, the opening of the door to the process chamber of the furnace may be prevented when the concentration of the selected gas exceeds a predetermined level.

Abstract: A bulk adhesive handling system (10) having a hopper (16) and a lid (26) includes a vapor removal system (12) comprising a plurality of vent holes (40) formed in the side wall (42) of the hopper (16) of the system. The vent holes (40) are in communication with a venting plenum (44) surrounding the hopper (16), which is connected to a vacuum source (46). The vapor removal system (12) is adapted to withdraw gas from the hopper (16) when the lid (26) is in an open position and to withdraw air from an ambient source when the lid (26) is in a closed position.

Abstract: In a baking oven for baking a relatively planar work such as semiconductor substrates, LCD panels and integrated circuit boards, a laterally elongated slot is formed in a shutter door which is moveable in the vertical direction. The oven main body is internally provided with a rack having a plurality of shelves which are each associated with the slot of the shutter door in such a manner that the work supported by each of the shelves of the rack may be aligned with the slot of the shutter door by appropriately determining the vertical position of the shutter door. Thus, by minimizing the area of the access opening of the oven main body, not only the loss of energy is minimized but also undesirable fluctuations in the internal temperature of the oven main body is minimized.

Abstract: An exhaust system for use with a high temperature furnace used to perform oxidation and/or annealing operations of the type used in semiconductor fabrication. The exhaust system is designed to permit the furnace to be used with a controlled environment chamber surrounding the entry to the process chamber of the furnace. The exhaust system allows a relatively high velocity flow of exhaust gas from the process chamber through the exhaust system to occur when a positive pressure (e.g., annealing) operations are performed. Such high velocity flow prevents (a) backstreaming and (b) the accumulation of non-uniform concentrations of exhaust gases in the exhaust system, thereby permitting the accurate monitoring of the concentration of a selected gas in the exhaust system. Based on such monitoring, the opening of the door to the process chamber of the furnace may be prevented when the concentration of the selected gas exceeds a predetermined level.

Abstract: Provided is an apparatus for producing a silicon nitride sintering body made of a furnace including a heater source. The furnace includes a furnace core chamber defined by at least one partition inside the furnace to prevent an atmosphere containing more than about 30 ppm of carbon monoxide from contacting said silicon nitride sintered body. At least an inner surface of the partition is made of a carbon-free heat-proof material which prevents formation of carbon monoxide gas in an atmosphere in contact with the silicon nitride sintered body during sintering. The furnace also includes a gas supply pipe for supplying an N.sub.2 gas or an inactive gas including an N.sub.2 gas into the furnace core. Also provided is a sintering case made of a vessel defining a sintering atmosphere. The vessel has an opening for loading an object to be sintered into the vessel.

Abstract: A titanium nitride film forming method employing an ion-plating method to produce good decorative properties, to a titanium nitride film forming method which can maintain the stability of the color tone even under high temperatures, and to the vessel obtained through the above methods.

Abstract: This invention relates to a combustion device for feeding hydrogen gas and oxygen gas into a combustion vessel, while heating the same, to generate water vapor. The combustion device comprises a hydrogen gas injection nozzle for feeding hydrogen gas into the combustion vessel, and an oxygen gas injection nozzles for feeding oxygen gas into the combustion vessel. The oxygen nozzles are projected further upward in the combustion vessel beyond the forward end of the hydrogen gas injection nozzle, and opened at a plurality of positions, whereby to diffuse oxygen widely around. The combustion device of this structure can feed a large amount of hydrogen gas for the combustion, whereby a large amount of water vapor can be generated without enlarging the combustion vessel, and troubles, such as the devitrification of the forward ends of the nozzles, abnormal heating in the combustion vessel.

Abstract: An induction heating furnace is disclosed comprising an induction coil assembly and a ladle having a metallic shell that supports a crucible holding metal to be heated by the furnace. The ladle is readily separated from the induction coil assembly so that the heated metal may be conveniently and reliably moved among operational stations. The induction coil assembly has a preselected length which is less than the length of the shell. The induction coil assembly surrounds, but does not touch the shell and generates an electromagnetic induction field. The induction coil assembly comprises a coil, upper and lower yokes and an intermediate yoke coextensive with the coil. The upper and lower yokes are separated from each other and electromagnetically coupled together by the intermediate yoke. The upper, lower and intermediate yokes each comprise stacked laminates formed of sheets of ferrous material.

Abstract: A crucible assembly for use in induction melting furnaces utilizes an inner crucible formed of partially stabilized zirconia and an outer support member formed of a sintered alumina. The crucibles are in the shape of a cylinder with a closed bottom wall and in the cylindrical wall area, the inner crucible and the outer support member are separated by a layer of porous ceramic fibers of alumina and silica and the entire assembly has been centered as a unit so that the outer support member with a porous layer allows for the thermal expansion and contraction of the inner crucible while limiting any stresses applied to the inner crucible and providing additional strength and support for the inner crucible.

Abstract: A heat-treatment apparatus comprises a heat-treatment section for subjecting a heat-treatment to a wafer and a loading section for loading a wafer boat into and unloading it from the heat-treatment section. The loading section is connected to the heat-treatment section and includes in it a movable support member, a drive mechanism and a vertical base board as well as a load-lock chamber for maintaining the inside in vacuum. The movable support member supports a wafer boat. The movable support member is attached to a vertical base board so that it can move up and down. The drive mechanism is attached on the major surface of the vertical base board opposite to the surface facing the wafer boat. The drive mechanism drives the movable support to move up and down. The heat-treatment apparatus further comprises a wafer transfer section that includes an orientation flat alignment mechanism and a buffer stage disposed near the orientation flat alignment mechanism.

Abstract: An exhaust system for use with a high temperature furnace used to perform oxidation and/or annealing operations of the type used in semiconductor fabrication. The exhaust system is designed to permit the furnace to be used with a controlled environment chamber surrounding the entry to the process chamber of the furnace. The exhaust system allows a relatively high velocity flow of exhaust gas from the process chamber through the exhaust system to occur when a positive pressure (e.g., annealing) operations are performed. Such high velocity flow prevents (a) backstreaming and (b) the accumulation of non-uniform concentrations of exhaust gases in the exhaust system, thereby permitting the accurate monitoring of the concentration of a selected gas in the exhaust system. Based on such monitoring, the opening of the door to the process chamber of the furnace may be prevented when the concentration of the selected gas exceeds a predetermined level.

Abstract: Graphite substrate holders for employment in apparatus for chemical vapor deposition of diamond decrease the tendency of the formed diamond sheets to crack or shatter upon separation from the substrates. Said holders and the substrates therein preferably have rounded edges, to suppress crack formation at sharp corners. The holders are preferably coated, at least in part, with a tie-layer and a hydride-forming metal such as niobium. Also, certain maximum distances between the edges of the holder and substrates are preferably maintained in order to prevent contact of diamond with a heated filament employed for thermal activation.

Abstract: The present invention includes a crucible which holds volatile material to be tested. The crucible is lowered into an oven apparatus and removed from the oven apparatus by equipment programmed in a predetermined manner.

Abstract: An interchangeable module for supporting a receptacle into which a molten sample, prepared by a fluxer, can be poured for analysis. One module can support a resistively heated casting dish into which a molten sample can be poured and cooled to form a solid sample for instrumental analysis. This module includes an insulator having a depression for receipt of a casting dish. A heating coil is positioned below the recession. A cooling gas conduit extends through the insulator support. The insulator is supported on a frame. The frame is supported on a back plate.

Abstract: An instrument and system for the preparation of a sample for analysis provides a crucible holder which improves the holding and control of a melting crucible during operation of the device for agitating a powdered sample and flux while being heated. The crucible holder is coupled to an agitation assembly which provides independently controlled operation on two different axes using separately adjustable variable frequency and amplitude motion along each of the two operating axes to provide an finite number of agitation patterns for the crucible. In one preferred embodiment of the invention, the heating flame is controlled by controlling the supply of compressed air and a combustion gas. In another preferred embodiment of the invention, a pilot burner is provided which both ignites the main burner located under the crucible and preheats the casting dish to a temperature which is substantially the same as the crucible.

Abstract: Apparatus for melting preferably highly reactive metals, such as titanium for example, in a vacuum melting furnace, for example a vacuum arc furnace for the remelting of metals, with one or more melting positions, a melting crucible (5, 28) being provided at each melting position, these crucibles being closed vacuum-tight after the end of the melting operation and then separated from the melting furnace, the furnace being provided with a single manipulator and by this manipulator each single crucible (5, 28) can be closed vacuum-tight by means of a separate crucible closure plate (13, 37).

Abstract: A system for safely disposing of pathogenic waste materials. The waste material is disposed in a chamber and heated by forced hot air to temperatures above approximately 450.degree. F. to destroy harmful bacteria within several minutes. The high temperatures melt plastic waste materials. The harmless waste is cooled providing a solid block in which syringes and other sharp items are generally encased. The temperature within the chamber is continuously sensed and the operation of the apparatus is microprocessor controlled to adjust the process time in accordance with the load size. The microprocessor further stores the sensed temperature to provide verification that the waste has been exposed to sufficient temperatures and for a sufficient time to render such waste harmless.

Abstract: A boron nitride crucible having a closed end, an open end, an internal surface and an external surface, and wherein at least a portion of the external surface, preferably proximate the open end of the crucible, has a duplex coating comprising an undercoat of pyrolytic graphite and a top coat of pyrolytic boron nitride. A process for making the boron nitride crucible is also disclosed.

Abstract: A unit for heating initially solid asphaltic material to provide asphaltic concrete in a condition suitable for application, including an inner enclosure defining a volume for containing the material to be heated, an outer enclosure surrounding and spaced from the inner enclosure to define a space beneath the inner enclosure and passages for heated air flow around the walls of the inner enclosure, a screw disposed in an open-top channel at the floor of the inner enclosure to move heated material, an opening in the inner enclosure floor in communication with a passage in the outer enclosure floor for delivery of heated asphaltic material moved by the screw to the unit exterior, heating chambers projecting upwardly from the floor of the inner enclosure above the heating sources to provide regions through which hot air rises from the sources, and flues extending transversely from the upper portions of the heating chamber to the end walls of the inner enclosure for conducting the heated air from the heating chamb

Abstract: A rotary kiln system wherein oxidant injection means are positioned at each stationary end and inject oxidant toward each other creating gas recirculation within the rotary kiln for improved mixing, combustion efficiency and temperature uniformity.