Abstract: A method for annealing a multilayer wafer by subjecting the wafer to a high temperature treatment that includes at least a temperature ramp-up between a boat-in temperature and a process of at least 800° C.; at least a processing phase in the range conduct at or above the process temperature; and a temperature ramp-down from the processing phase to a boat-out temperature. The boat-in temperature is sufficiently lower than the boat-out temperature to reduce or avoid tearing-off defects on the wafer and to reduce particle contaminants on the wafer, as well as to reduce or avoid degrading wafer Dit compared to an annealing method where the boat-in and boat-out temperatures are closer in temperature.

Abstract: A heating apparatus has first through fifth heating furnace arranged along the feeding direction in which glass substrates are fed by a feeding mechanism. The first heating furnace has a first heater for heating a glass substrate to at least a target temperature required for processing the workpiece. The second heating furnace has a heater for heating a glass substrate to a temperature equal to or below the target temperature. The second heating furnace generates an amount of heat smaller than that of the first heating furnace.

Abstract: A heat treating apparatus includes a heating plate for heating a substrate coated with a coating liquid, a cooling plate for cooling the substrate and a heat pipe provided in the cooling plate, a cooling chamber being moved together with the cooling plate by the drive mechanism and accommodating a cooling liquid for cooling one end side of the heat pipe. The apparatus further includes a circulation passage provided in the heat treating apparatus to circulate the cooling liquid in the cooling chamber, a circulation pump for circulating the cooling liquid in the circulation passage; and a heat radiating member provided on the circulation passage to radiate the heat received by the cooling chamber to the outside of the heat treating apparatus.

Abstract: A process of manufacturing a sulfoaluminate or ferroaluminate cement, and an apparatus for the manufacture. The cement is manufactured from a mixture containing CaCO3, Al3 and/or Al(OH)3, CaSO4, SiO2 and/or a product containing silica or silicates such as clay, these compounds being present in the anhydrous or hydrated form. In this process, the mixture is treated up to clinkering by movement in a center of a kiln, in a sheet with approximately constant thickness, at approximately constant speed, along a treatment path having a positive temperature gradient, and for a treatment time during which the mixture remains below its melting temperature. The mixture is clinkered to produce a clinkered mixture that is cooled upon exit from the treatment path.

Abstract: Method of reducing the wrinkles formed in heating zones, by radiant tubes, of continuous heat treatment lines for metal strip, such as annealing or galvanizing lines, the said strip passing over transporting and/or return rollers in the said furnaces, the said method, which consists in modifying the thermal state of the rollers, being characterized in that the said modification is made directly by varying the heating by the said radiant tubes located near the rollers, thereby directly controlling the heat flux emitted by the radiant tubes towards the rollers.

Abstract: An element control system (32) that reduces the effects on image quality of thermal distortions in an optical element (28) of a lithography system (10) includes a heat source (50) that primarily heats a non-illuminated region (44) of the optical element (28) to alter and/or control the shape of the illuminated part of the optical element (28). The heat source (50) directs heat to the non-illuminated region (44) and/or an illuminated region (42) to simplify and/or alter the shape of thermal distortions aberrations in the optical element (28).

Abstract: In a process to control the heating of a coating material for a roof covering, the coating material is heated using a heat exchange medium in a continuous process. The heat exchange medium is cooled in response to a slowdown or stoppage of the continuous heating process to maintain the temperature of the coating material below a predetermined level.

Abstract: The apparatus of the present invention provides for the dual use of a UV source to heat a substrate and to facilitate photochemistry necessary for the treatment of the substrate. The present invention also provides a method for processing a substrate by heating the substrate to a temperature above ambient via UV radiation at a first power level and conditioning the substrate by exposing the substrate to a photochemically (UV) reactive chemical, or a reactive chemical that can react with a compound on the surface of the substrate to form a photochemically reactive compound, in the presence of UV radiation at a second power level.

Abstract: An improved method is disclosed for heat curing a polymerizable impregnant composition within an impregnated porous article. The amount of the article's porosity that is filled with the impregnant composition is maximized by applying successively discrete temperature and pressure increments in a system comprising at least one porous impregnated article and a curing chamber having a heat transfer medium therein. During such curing, both temperature and pressure are controlled for an initial duration and subsequently increased by successive increments wherein each successive temperature and pressure exceeds a previous temperature and pressure, respectively, until a maximum temperature and pressure is achieved. The maximum temperature and pressure are maintained until the impregnant composition is cured, resulting in an improved product having greater structural integrity and surface quality.

Abstract: A tungsten powder having a powder specific surface of 0.4 m2/g or more is hot-pressed at a temperature of 1,600° C. or more and then subjected to HIP at a temperature of 1,700° C. or more without capsuling, whereby a tungsten target for sputtering is manufactured that has a relative density of 99% or more and an average crystal grain size of 100 &mgr;m or less. This manufacturing method can manufacture, stably at a low cost, a tungsten target having such a high density and fine crystal structure as cannot be attained by the conventional pressure sintering method, and can greatly decrease the number of particle defects on a film produced by using such a target.

Abstract: A method and apparatus for accelerated cooling of a furnace such as a furnace containing a susceptor. Cooling gases are split whereby a first percentage are provided to cool the furnace while a second percentage are provided to assist in cooling the heated cooling gases after cooling the furnace, whereby the percentages are changed throughout the process. The system further provides for unique cooling flow arrangement in the furnace which promotes maximum heat transfer through swirling.

Abstract: An apparatus and method for fabricating fiber gratings from optical fibers by imposing constant or variable chiral refractive index modulation along an optical fiber. The refractive index modulation may be of single helix symmetry to produce a fiber grating enabling different propagation speed of signals with the same handedness as the structure with respect to signals with opposite handedness as the structure at a wavelength substantially equal to the pitch of the single helix, or of double helix symmetry to produce a chiral fiber Bragg grating. In several embodiments of the present invention the refractive index modulation is imposed by twisting and moving a specially prepared optical fiber through a heater that heats a small region of the fiber to a temperature sufficient to allow the fiber to twist in that region as it moves through the heater.

Abstract: Apparatus for heat treating a heat treatable material including a housing having an upper opening for receiving a heat treatable material at a first temperature, a lower opening, and a chamber therebetween for heating the heat treatable material to a second temperature higher than the first temperature as the heat treatable material moves through the chamber from the upper to the lower opening. A gas supply assembly is operatively engaged to the housing at the lower opening, and includes a source of gas, a gas delivery assembly for delivering the gas through a plurality of pathways into the housing in countercurrent flow to movement of the heat treatable material, whereby the heat treatable material passes through the lower opening at the second temperature, and a control assembly for controlling conditions within the chamber to enable the heat treatable material to reach the second temperature and pass through the lower opening at the second temperature as a heated material.

Abstract: A metal workpiece to which a brazing material and a flux are previously adhered is set into an index type convection furnace, and a heating medium gas is blown to this metal workpiece, so that the temperatures of the workpiece are increased up to the brazing temperature. After that, the temperatures of the heating medium gas are varied between the temperature slightly higher than the brazing temperature and the temperature at least 5% lower than that, in a predetermined period, while brazing. According to this method, a temperature slope of the workpiece is eliminated and uniform brazing is possible.

Abstract: A method and apparatus for the carbonization of polyacrylonitrile (PAN) precursor fibers. The apparatus comprises a furnace, or series of furnaces in side-by-side arrangement. Each furnace includes a heater, an air inlet and an air diffusion plate. The fiber is located in the furnace above the air diffuser plate, such that heated air is evenly dispersed over the fibers. The method generally comprises the steps of heat treating the PAN precursor in an oxidizing environment to stabilize the fiber, and then further heat treating the stabilized fiber in an oxidizing environment to carbonize the stabilized fiber. The method can be carried out in a single furnace, or can be carried out in a series of furnaces in a continuous process.

Abstract: Firing process and apparatus for uniformly heat-treating a substrate having a film-forming composition thereon, wherein the substrate is subjected to a first soaking step in which the substrate is held for a predetermined time in a first heating chamber whose temperature is maintained at a first value, so that the temperature within the substrate is held at the first value evenly throughout an entire mass of the substrate, and after feeding of the substrate into a second heating chamber whose temperature is maintained at a predetermined second value which is different from the first value by a predetermined difference, the substrate is subjected to a second soaking step in which the substrate is held for a second predetermined time in the second heating chamber, so that the temperature within the substrate is held at the second value evenly throughout the entire mass of the substrate.

Abstract: The invention relates to a method for heating a furnace comprising at least one burner capable of operating on an oxidant the oxygen content of which can vary; in a first period (P1) the burner is supplied with practically pure oxygen so as to provide a large amount of energy for heating, in a second period (P2) the burner is supplied with an oxidant, the oxygen content of which can vary between about 100% and 21%, in a third period (P3), the burner is supplied with an oxidant, the oxygen content of which is minimal, and which corresponds to a pilot period which requires only a small amount of heating energy. This method makes it possible to optimize the use of the furnace according to the desired thermal performance and oxidant operating costs.

Abstract: In a combustion installation for burning a fuel, which installation includes a hearth operating as a circulating fluidized bed, and in which installation at least a fraction of the flow of solid particles resulting from the combustion of the fuel in the hearth is returned to the hearth via a heat exchanger operating as a fluidized bed, the method of decreasing nitrogen oxide emissions consisting in the heat exchanger being fed with a fluidization gas which is considerably poorer in oxygen than air.

Abstract: A device adapted for attachment to a thermal processing furnace, the device includes a housing having first and second openings with a chamber located therebetween, the second opening is operatively connected to a thermal processing furnace and in communication with the thermal processing furnace for receiving a thermal process generating gas stream containing combustibles from the thermal processing furnace, a gas supply assembly located within the chamber for supplying a heated oxygen-containing gas at a temperature and velocity sufficient to mix the combustibles and the oxygen-containing gas to oxidize the combustibles into harmless byproducts.

Abstract: A method for processing a pulverulent calcium sulphate material in order to obtain a hydraulic binder is described, including combining the following two successive processing steps: (a) heating the pulverulent material in a curing tunnel (1) at a temperature of 220-360° C., under conditions suitable for primarily forming an &agr;-type calcium sulphate, and (b) subjecting the heated material to a thermal quenching step in a cooling apparatus (2), with a cold, dry gas to stabilise the &agr; anhydrite and to prevent its conversion into other crystallographic types. The method provides a novel hydraulic binder with an &agr; anhydrite content of more than 35 wt. %, and with improved strength and behavior in fire resistance properties.

Abstract: In a method wherein semiconductor wafers are accommodated within a treatment furnace that has been heated beforehand to a predetermined temperature, the temperature within the treatment furnace is increased to a predetermined treatment temperature, and the semiconductor wafers are subjected to an oxidation treatment, the temperature-increasing step is performed under a reduced pressure. This makes it possible to suppress the formation of natural oxide films during the temperature-increasing step, and thus makes it possible to form an extremely thin film of a superior quality on the semiconductor wafer.

Abstract: A method of cooling a regenerative thermal oxidizer down rapidly includes the steps of increasing the cycle time of the heat exchangers once a decision has been made to shut the regenerative thermal oxidizer down. By increasing the cycle time, the regenerative thermal oxidizer rejects more heat from the system. That is, the efficiency of the system goes down, and more heat is lost. In this way, the system approaches an ambient temperature much more quickly then in known systems. In one method of performing this invention, the cycle time is increased as much as possible, and as rapidly as possible while monitoring the outlet temperature on the outlet gas. The cycles are reversed only when the outlet temperature approaches a maximum safe operating temperature. In a second method, the cycle times are increased in pre-programmed steps. By utilizing the present invention, one is able to cool a regenerative thermal oxidizer to ambient temperatures in less than half the time of the prior art systems.

Abstract: A method for forming a socket on a pipe of biaxially oriented polyvinyl chloride including: placing a support in an end section of the pipe, heating the pipe in the region of the end section; deforming the pipe to produce a socket in the region of the heated end section, the heated end section being supported internally while the socket is being formed; cooling the pipe in the region of the end section, the end section being supported internally during the cooling operation; and removing the support from the pipe. For the purpose of heating the internally supported end section of the pipe, the end section is first heated until the end section has reached, substantially homogeneously, the glass transition temperature of polyvinyl chloride and is then further heated until the end section has reached, substantially homogeneously, a temperature near, preferably just above, the orientation temperature of polyvinyl chloride.

Abstract: A method for heating a glass sheet includes the steps of heating a glass sheet to a first predetermined temperature and applying microwave energy to the glass sheet to heat the glass sheet to at least a second predetermined temperature to allow the glass sheet to be formed.

Abstract: A heat treatment apparatus comprising a reaction vessel located in a vertical furnace, and a ladder boat for mounting a plurality of semiconductor wafers one above another in parallel with each other. A vertical mounting pitch of mounting the wafers on the ladder boat is set at, e.g., 40 mm. When a treatment temperature is 1000.degree. C., intra-surface temperature differences of the wafers, objects to be treated, can be suppressed to 10.degree. C. at the time of passing 900.degree. C. even when 600.degree. C. is raised to 100.degree. C. at a 100.degree. C./min rate, whereby no slip occurs in large-diameter semiconductor wafers of an above 250 mm diameter even with high temperature increases at high rates in heat treatments, as of oxidation, diffusion, etc.

Abstract: A process for the continuous fluidized bed agglomeration of a solid in powder form, wherein the powder, a granulating liquid and propelling air are fed through a three-substance nozzle into the center of a fluidized bed to form a three-phase mixture in the center of the fluidized bed.

Abstract: A cooling system for annealing material (4) in the form of plates, strips or bulk material moving on a transport means (5) consists of a plurality of zones (1, 2, 3), in which the annealing material (4) is treated on its lower and/or upper surface with an oblique blast of cooling medium in the form of air or gas emerging from nozzles of nozzle bars (10, 10a, 10b) fed by a compressor-type blower (7, 8, 8a, 11). In order to reduce the required amount of cooling medium, and to reduce the technical effort involved, only the last zone (3) disposed on the outlet end for the annealing material (4) is connected to the supply (7) of pressurized fresh cooling medium. In this zone (3) a collecting fan (8, 11) is provided, which upon formation of the oblique blast urges the cooling medium into a distribution box (9). To the distribution box (9, 12) the nozzle bars (10) of the penultimate zone (2) are connected.

Abstract: A kiln and method of firing kilns or the like in which high firing rate gas streams are introduced into the ware treating chamber in the form of pulsed jets and a continuous low firing rate gas stream is also introduced into the ware treating chamber for maintaining uniformity of temperature and atmosphere within the ware treating chamber. The time interval between the pulsed jets is controlled in accordance with the difference between a set predetermined temperature and the actual temperature in the ware treating chamber. Also disclosed is a burner for the kiln including coaxial primary and secondary nozzles for burning fuel. The primary nozzle burns fuel at a high rate and is pulsed intermittently while the secondary nozzle burns constantly at a low rate.

Abstract: A heated crucible apparatus allows the adjustment of a thermal profile within a combustion chamber surrounding the crucible by introducing a sub-stoichiometric or a super-stoichiometric mixture of fuel and oxidant into the combustion chamber and varying the oxidant flow for sub-stoichiometric or fuel flow for super-stoichiometric downstream of the initial combustion to control the release of heat in defined areas within the combustion chamber. The adjustable thermal control system allows for an even thermal energy release or varying thermal energy release over the length of the crucible. The apparatus a crucible having an inlet and and outlet surrounded by the combustion chamber which chamber includes an oxidant and fuel supply at the primary injection point followed by secondary injection of the remaining oxidant supply for sub-stoichiometric (or fuel supply for super-stoichiometric) at specific intervals to achieve the desired thermal profile and heating of the crucible.

Abstract: A method for sintering industrial waste into environment conserving stones. The process mixes waste industrial earth and industrial waste in a predetermined ratio, and forms sterile environment protecting stones with high strength by the following processes: vacuum ejection, drying, breaking, screening, separating, sintering, and vibrating screening. The stones can be uses in the construction of civil engineering projects, or used as stone additives in asphalt pavement.

Abstract: Process and device for the treatment of lumpy products using process media, the treatment including a predetermined sequence of process steps. A chain of treatment units is moved in a stepwise manner. The product to be treated remains within the same treatment unit for the duration of the sequence of the process steps. A supply unit supplies and removes process media in a stopping-station specific manner so that the process steps can proceed simultaneously in the treatment units.

Abstract: A method for depositing sequential thin films on glass substrates by single substrate deposition comprising loading a batch of substrates into a load lock chamber and evacuating the chamber, transferring the substrates to a batch heating chamber for heating the substrates to elevated temperatures; transferring the glass substrates singly to one or more single substrate processing chambers, and sequentially transferring the substrates back to the load lock chamber where they are batch cooled.A vacuum system for carrying out the method includes a load lock/cooling chamber for evacuating a plurality of glass substrates; a heating chamber for heating a plurality of substrates to elevated temperatures; one or more single substrate processing chambers; and a transfer chamber having access to all of said chambers and having automated means therein for transferring the glass substrates into and out of said chambers in a preselected order.

Abstract: A ring section furnace device for the calcination of carbon bodies includes a number of serially connected chambers with or without lids on top. Each chamber contains a number of cassettes the walls of which have therein vertical and/or horizontal flue gas channels. A flue gas exhaust system from each chamber leads to a main ring duct. The furnace is fitted with an additional, separately attached ring duct, and each of the chambers is fitted with a recovery device in the form of a lid, manifold, or a similar device with a closeable opening or joining pipe, which allows for exhaust removal of the air used for cooling the cassettes through a pipe connection fitted between the additional ring duct and the recovery device on the chamber.

Abstract: For use in the fabrication of electronic circuit modules, there is provided a heating furnace which can be arbitrarily set in a desired temperature profile. The furnace includes a plural number of independently controllable heaters located in spaced positions to provide a plural number of heating zones in the furnace, and a plural number of cooling panels provided in the heating zones of the respective heaters. Each heater is independently controlled according to a specified type of substrate to establish a temperature profile for the specified substrate type in the furnace to carry out the curing of a sealing synthetic resin material of a semiconductor device and the reflow soldering of surface mounting devices in one and single furnace.

Abstract: An Au/si die attach method for attaching a die to a package including preheating the package, melting an Au/Si preform in the package cavity, scratching the die onto the package cavity to form a die attach bond, and gradually cooling an Au/Si die bond by reducing heat supplied to the package, so as to cool the package through a monotonically decreasing sequence of temperatures, wherein the package is maintained for a predetermined period of time at each temperature in the sequence.A heating block with segments supplies a decreasing amount of heat to the packages to let the die attached bond gradually cool. The packages are kept on top of the segments of the heating block for a predetermined period of time and each segment is heated to a specific temperature. The gradual cooling of the die attach bond decreases the thermal resistance and prevents the creation of voids in the die attach bond.

Abstract: A gas burner assembly for a baking furnace is described. It includes a burner tube having an open outer end and an open inner end, with the inner end being arranged to extend through an opening in a furnace wall. A connector is provided for connecting the burner tube to a fuel supply and an infra-red pyrometer is mounted at the outer end of the tube. The pyrometer is axially aligned with the burner tube such that in use the pyrometer is sighted axially through the burner tube and onto an internal furnace wall. This gas burner assembly is particularly useful for heating the flue of a ring furnace used in the production of carbon anodes in the aluminum industry.

Abstract: A process for firing ceramic shaped bodies is disclosed, which comprises the step of making a heating temperature in a temperature range up to a decomposing temperature of a shaping aid contained in the ceramic shaped body smaller than that in a temperature range from the decomposing temperature to a firing temperature. A tunnel kiln is also disclosed, which comprises a preheating zone, a firing zone, a waste heat zone, combustion burners provided at the firing zone, an exhaust means provided at an inlet side of the preheating zone for evacuating combustion gases from the combustion burners outside the kiln, and another exhaust means provided at an outlet side of the preheating zone for evacuating the combustion gases outside the kiln.

Abstract: Disclosed is a method of controlling the temperature of a joining area between two different strip materials in a continuous strip processing line. In the case where a strip material after the joining area requires a nozzle pressure greater than that of a preceding strip material, the opening of a damper is initially gradually throttled, at a timing before the joining area passes through a predetermined location in a treating furnace, by an amount required for changing the nozzle pressure so that an optimum pressure of the preceding strip material is changed so that of the following strip material. The rotational speed of a recirculation fan is then raised to keep the nozzle pressure substantially constant, and the damper is rapidly opened to the opening before the throttling at a time the joining area passes through the predetermined location.

Abstract: The invention relates to the control of a tunnel furnace partitioned into a plurality of zones for heat treatment of, e.g., ceramic or glass workpieces. As usual the temperatures of the respective zones are controllable individually. Furthermore, in each of selected zones the temperature of that zone is varied from a first level to a second level during the stay of each workpiece in that zone and returned to the first level in a predetermined time after letting the workpiece out of that zone, and the length of stay of each workpiece in that zone is controlled such that another workpiece can be introduced into that zone while the preceding workpiece stays in the next zone and such that a number of workpieces can be heat treated in succession under the same time-temperature conditions.

Abstract: An apparatus for precisely heating a continuous stream of heading tool dies to a desired temperature for immediate use thereafter in a rivet heading operation comprises a closed-loop transport system having a variable-speed drive and receptacle means for receiving and retaining heading tool dies for transportation therewith, with a first section of the die transport system being exposed to fluid medium having reference temperature below the desired die temperature, and a second fixed-length section of the die transport system being exposed to a constant temperature heat source. The temperature of the dies is thus normalized by exposure to the reference temperature fluid medium, whereafter a metered quantity of heat is transferred to each die by the controlled exposure thereof to the constant temperature heat source as determined by adjustment of die transport speed, whereby the dies are precisely heated to the desired temperature.

Abstract: A plurality of burners are provided for burning a combustible gas mixture. A conduit extends to each of the burners for supplying a combustible gas mixture thereto. A mixing device is coupled between the conduit and a source of air and a source of combustible gas for mixing combustible gas and air for flow to the conduit. An air valve is coupled between the source of air and the mixing device for controlling the flow of air to the mixing device. First and second gas valves are coupled between the source of combustible gas and the mixing device. A control circuit is provided which is adapted to be operated in a flame intensity cycle of high/low flame or in a burner on/off cycle. In the flame intensity cycle, flow of air through the air valve is cyclically increased and decreased and gas flows continuously through the second gas valve for cyclically increasing and decreasing the flame intensity at each of the burners.

Abstract: In heating control method of a heat furnace, three non-linear models, model to calculate furnace temperature based on the fuel flow rate by unsteady heat balance system, model to estimate furnace wall temperature distribution based on the furnace temperature and model to estimate material temperature based on the furnace temperature, are used, linearization is performed by perturbation simulation to vary the flow rate stepwise and the optimization to minimize the fuel flow rate is performed and the optimum furnace temperature per each material is determined, and the mixed combustion ratio of plural fuels obtained by dividing total calorific value of each fuel by total calorific value of all fuels and the furnace temperature setting value are calculated using the optimum furnace temperature per material and then set.

Abstract: A rotary kiln, in particular, a kiln for reburning of lime mud, wherein the drying and intermediate zones of the kiln chamber are furnished in part with turbulence-forming baffle arrangements to produce a turbulent motion in the hot combustion gases and thereby to force the hotter gases, which flow through the axial central region of the kiln, out towards the kiln wall. The kiln shell is additionally furnished in part with thresholds in order to increase the transit time of the material through the kiln and further with lifters and a cog-wheel lining in order to lift the material and bring it into contact with the gases. The burner tube can be furnished with turbulence-forming baffles and the surrounding kiln shell with lifters and with thresholds at both ends of the burner tube. The baffles are preferably conical in cross-section with the apices coincident with the center of the cross-section of the kiln.

Abstract: A method of controlling the rolling efficiency in a continuous hot rolling process. A rolling schedule and a conveying schedule are determined on a mill line for the slabs arranged in succession based on an aimed extraction temperature of the slabs from a heating furnace and a predetermined temperature at the exit of a finish mill. A minimum extraction pitch is calculated for the slabs from the heating furnace under restriction of the side of the mill line, and a different minimum extraction pitch is calculated for slabs from the heating furnace under restriction of the side of the heating furnace based on slab temperature charged to the heating furnace and the aimed extraction temperature. An optimum extraction pitch is determined for slabs from the heating furnace by comparing both of the minimum extraction pitches. With such a method, the continuous hot rolling operation is carried out under an optimum condition.

Abstract: A method of operating a controlled atmosphere furnace. To prevent the entry of oxygen into the controlled atmosphere in the chamber of the furnace, which has a furnace door for the receipt and removal of parts by means of a feeding and removal device, the device is designed to seal a vestibule located immediately in front of the furnace door when the device approaches the furnace door. The oxygen-containing ambient air thus trapped in the vestibule is then removed therefrom. The furnace door is opened, and the feeding and removal device, while still sealing the vestibule from the ambient air, then moves into the furnace chamber for feeding or removing the part which is to be heat treated.

Abstract: A plant for preheating and, possibly, heat-treating bars (2) of aluminum or aluminum alloys and subsequently severing the bars (2) into slugs (10) comprises a furnace (4) for the heat treatment and preheating only, if desired, billet hot shears (7), and a quick preheating furnace (16) connected between the hot shears and the furnace. Upon selection of the operating mode of heat treatment of the bars (2), the quick preheating furnace serves as cooling apparatus providing for temperature controlled cooling and corresponding renewed heating to a predetermined billet pressing temperature when the admissible temperature is not reached. When the plant operates alone to preheat the material, the quick preheating furnace serves as preheating furnace the exhaust gases of which serve to preheat the bars (2) in the furnace (4) through an exhaust gas conduit (19). This plant permits particularly economic and flexible operation, i.e.

Abstract: A method and system is provided for controlling a selected zone in a fuel fired furnace of the type used for heating work as it moves through the zone from an entrant end to an exit end. The method and system includes providing a fuel fired burner at the exit end for propelling a flame toward the entrant end of the zone, controlling the firing rate or capacity of this flame in accordance with the temperature of the work adjacent the exit end of the zone, continuously establishing a gas temperature for the entrant end of the zone corresponding to the firing rate of the flame and then continuously controlling the length of the flame to obtain the established gas temperature at the entrant end of the zone. The combined adjustment of capacity and flame length in accordance with the measured temperature at the entrant end of the zone controls the heating profile through the zone and increases the efficiency of the heating zone.

Abstract: A ring section baking furnace for the indirect heating of shaped bodies or particulate material, particularly for calcination, includes vertical ducts, or channels, in pit walls arranged in groups by means of partition walls under the bottom of the pits. Flue gases are led up and down through these ducts. Combustion chambers are not provided, and the volume thereof otherwise required is incorporated into the pit volume. The ducts in each pit wall lead out over the pit wall into one or more separate rooms which connect, in series, two neighboring groups in this pit wall. A small cover plate is provided over each pit wall. Compared with earlier designs with the same external dimensions, less refractory brick is required, a more even temperature of the calcined material is achieved, the consumption of fuel is reduced and the capacity increased.

Abstract: A high gradient directional solidification furnace is disclosed which includes eight thermal zones throughout the length of the furnace. In the hot end of the furnace, furnace elements (25, 26, and 40) provide desired temperatures. These elements include Nichrome wire (28) received in a grooved tube (30) which is encapsulated by an outer alumina core (32). A booster heater (40) is provided in the hot end of the furnace which includes toroidal tungsten/rhenium wire (42) which has a capacity to put heat quickly into the furnace. An adiabatic zone is provided by insulation barrier (62) to separate the hot end of the furnace from a cold end. The cold end of the furnace is defined by heating elements (80 and 90). A heat transfer plate (70) provides a means by which heat may be extracted from the furnace and conducted away through liquid cooled jackets (72).

Abstract: An installation is disclosed for processing a wet slurry of raw materials for cement manufacture having from 28% to 45% of water, the installation comprising a horizontal centrifugal separator connected to an extruder which produces slugs of partially dewatered material which is then pelletized and fed to a rotary Portland cement kiln. The extruded slugs can be admixed with dry powdery material to prevent their sticking together and to introduce powdery dry material in the kiln.