Abstract: The present invention provides a method and apparatus for determining the temperature of an object as it moves through a heat treating furnace. The furnace includes a hearth adapted to move through it thusly enabling a number of objects placed on the hearth to be heat treated as they move through the furnace. To obtain the temperature of an object being heat treated as it moves through the furnace, a hole is provided in the hearth. A thermocouple wire is inserted through the hole and into the furnace. An end of the wire is connected to an object being heat treated, and the object is placed in the furnace. The other end of the wire is connected to a temperature display device outside of the furnace which moves along with the hearth and the object as they move through the furnace.

Abstract: A procelain enameling furnace includes a combined entrance/exit zone, an air seal section, a radiation/convection heat transfer section, and a heating section. The entrance/exit zone receives an incoming cool ware and discharges an outgoing hot ware at substantially the same location. The air seal section prevents loss of heat from the furnace through the entrance/exit zone. In the heat transfer section, the incoming ware is parallel to and travels in the opposite direction to the outgoing ware for transferring heat therebetween by radiation and convection. The heating section includes a pre-heating zone and at least one heating zone. The pre-heating zone is formed of U-shaped heat exchanger tubes through which the incoming ware passes following the heat transfer section. The heating zone is formed of U-shaped radiant heating tubes for heating the cool ware following the pre-heating zone.

Abstract: A food preparation oven for baking foods which require less heat energy input into a first surface than into a second surface such as pizzas. A radiant panel is provided which is heated by means of hot air and which is positioned to heat one surface of the food product by radiant heat energy. The second surface of the food product is heated by means of a flow of hot air. The air is heated in a heating chamber and recirculated by means of a fan. The food product is supported on a conveyor belt and travels through the food preparation oven while it is being baked.

Abstract: This invention relates to a method of and a walking beam furnace for the intermediate heating of pipes, or the like, in hot rolling mills, by means of a furnace located between the plug-mill and the sizing mill. According to the invention, in a forehearth (17) of the intermediate heating furnace, at the inlet side thereof, there is maintained a temperature which is lower than that at the outlet side, and which, anyway, is such that the hottest pipes will be cooled down and the coldest pipes will be heated up whereby, when exiting from said forehearth (17) of the furnace, the difference between the temperatures of the various pipes is zero or, at least, is small and, in any case, is smaller than that at the inlet, whereas in the successive chamber (18) of the furnace there is maintained such a temperature as to give the pipes the desired temperature when exiting from the furnace.

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 method is disclosed for thermally conditioning an essentially tubular parison of polyethylene terephthalate material to a desired orientation temperature at which the polyethylene terephthalate material can be biaxially stretched. The method comprises the steps of heating the parison by applying heat to the exterior surface thereof until the surface reaches a maximum heating temperature less than the temperature at which the polyethylene terephthalate material begins to crystalize and then cooling the heated exterior surface of the parison to remove the heat therefrom while the heat within the wall of the parison diffuses therethrough to raise the temperature of the opposing interior surface toward the desired orientation temperature.

Abstract: A method for annealing semiconductor samples, especially following ion-implantation of semiconductor samples is disclosed. A furnace on a set of rails is passed over the semiconductor sample which is supported on a stationary wire basket made of low thermal mass, fine tungsten wire. The furnace temperature may be about 5.degree. above the desired anneal temperature of the semiconductor sample such that the sample temperature rises to within a few degrees of the furnace temperature within seconds. Utilizing the moveable furnace insures uniform heating without elaborate temperature control or expensive beam generating equipment.The apparatus and process of the present invention are utilized for rapid annealing of ion-implanted indium phosphide semiconductors within 10 to 30 seconds and at temperatures of approximately 700.degree. C., thereby eliminating undesired and damaging movement of impurities within the ion-implanted InP.

Abstract: A heating device including a flame burner (40) and a nozzle (52) into which the flame (50) from the burner (40) is directed and in which process air is mixed with products of combustion from the flame; the nozzle (52) having hot gas discharge openings (106) through which the hot gases resulting from the mixing action are projected onto articles (10) or other material to be heated.

Abstract: A cantilever tube for carrying loaded wafer boats into a diffusion furnace and confining flow of gas through the wafers includes an elongated slot extending from an open end of the tube to a predetermined region in which the wafer boats are positioned, the wafer boats abutting each other and forming a sealing cover for the elongated slot. A narrow boat carrier supported on a carriage system extends through the elongated slot and carries a wafer boat loaded with wafers into the open end and to the predetermined region in the cantilever tube without allowing either the carrier, or the wafer boat, or the wafers to touch the cantilever tube. The carrier lowers the boat onto the bottom inner surface of the tube, causing the boat to cover a portion of the elongated slot. The procedure is repeated for subsequent wafer boats, each of which abuts the previous one, to effectively close and seal the elongated slot when all of the wafer boats are positioned inside the cantilever tube.

Abstract: A cantilever diffusion tube apparatus includes a quartz cantilever tube having a support end clamped to a laterally movable carriage mechanism and an outer end portion containing a plurality of spaced semiconductor wafers. The cantilever tube is coaxially aligned with a diffusion tube of a diffusion furnace. The support end of the cantilever tube is sealed by a door plate through which a gas tube extends. The wafers are loaded into the cantilever tube through a window opening. The carriage then moves the cantilever tube and wafers therein into the diffusion tube. Reactant gases are caused to flow into the cantilever tube, between the heated wafers therein, and out of the cantilever tube. Then purging gas is caused to flow through the cantilever tube and wafers therein.

Abstract: The process treats a continuous stream of containers of solid material effecting melting or heating of the material within the package. The dwell time within the process is minimized while at the same time the maximum temperature achieved by any of the material is held within an allowable maximum.

Abstract: An improved semiconductor wafer handling system completely eliminates the need for boats, sleds, paddles, wheeled carriers, etc., customarily employed in transporting wafers during heat processing through the use of a plurality of rigid, polished cantilevered rods having a multiplicity of spaced slots for cooperatively holding wafers in an upright position. The system provides a means for achieving higher production yields of such semiconductor elements by generating fewer contaminating particles and through less exposure to ambient environment.

Abstract: In the resist baking apparatus disclosed herein, heating of the wafer is effected by direct contact with a thin disc-like heating plate whose heat capacity is not greatly disparate from that of the wafer. The heating plate is initially brought to a temperature higher than that which is to be applied to the resist but the corresponding cooling of the plate as the wafer is initially heated prevents damaging temperatures from reaching the resist. The heater plate is perforate and air pressure is utilized to support a wafer over the heater plate before heating is to begin and also to later lift the wafer and thereby sharply define the end of heating. During baking, a vacuum is applied through these same perforations to clamp the wafer tightly against the heating plate for tight thermal coupling.

Abstract: A conveyor is driven in a helical endless fashion within a horizontally annular baking chamber while carrying products to be baked. The air within the chamber is heated by means of burners disposed beneath the conveyor and in non-parallel relationship thereto. Heated air is drawn through an air permeable cover across the top of the chamber and into an upper air space thereabove. The air is circulated from that upper air space to a lower air space located beneath the chamber. The air is then circulated into the chamber through an air permeable floor disposed across the bottom of the chamber. The permeability of the cover and floor varies in order to assure a uniform passage of heated air therethrough.

Abstract: A wafer handling method and apparatus insures proper centering of a wafer at a work station and controls the heat transferred to the wafer in a baking operation. The amount of heat transferred and the rate at which the heat is transferred to the wafer are regulated by controlling the distance between the wafer and a hot plate. The hot plate is maintained at a constant temperature higher than the bake out or equilibrium temperature to which the wafer is to be heated.

Abstract: Inside a furnace body a number of material-stay spaces are set along a predetermined circular locus of travel of materials to be treated. The furnace body is divided into a heating chamber and a cooling chamber, and some of the stay spaces are located in the former chamber while the others are in the latter. A material is placed into one of the stay spaces located in the heating chamber, and heated therein. Then the material is moved into and stopped at one of the stay spaces located in the cooling chamber, and cooled therein. This process of heating and cooling the material is repeated a predetermined number of times so as to treat the material as desired.

Abstract: This invention relates to the walking beam furnaces--particularly of the bilateral-heating type, with fixed and/or walking beams (1, 2) cooled by means of water or other fluid--for the heating of metallurgical products (B), such as billets, blooms or the like. The invention aims to eliminate or minimize the localized cooling effect on metallurgical products where they contact the cooled beams, which cooling generates the so-called skid marks on said metallurgical products.For this purpose, the invention provides a method wherein each metallurgical article is turned over 180.degree. at least once around its longitudinal axis at a region in the furnace which is near the discharge end (18) of the furnace.

Abstract: A continuous combustion furnace in which the charges to be heat processed is passed through the tunnel in the kiln having three temperature zones comprising a preheating zone, a firing zone subsequent to the preheating zone and a cooling zone subsequent to the firing zone, wherein turbulant flows of atmosphere are induced in each of the temperature zones so that the charges are preheated, fired and thereafter cooled uniformly.

Abstract: The present invention relates to a method for the continuous firing of green ceramic articles, such as capacitors. In accordance with the invention a mixture of articles to be fired and heat resistant particulate matter in selected proportions is caused to descend a heated tube defining a furnace. Articles and particulate material such as sand are continuously introduced at the upper end of the furnace and removed at the lower end, after a predetermined dwell time within the furnace to effect firing. Removal is effected by progressively advancing a conveyer which is in partial blocking condition of the lower end of the furnace across the lower end of said furnace whereby the mixture of sand and fired ceramic articles is removed at a selected rate which is a function of the speed of the conveyer, whereby the dwell time in the furnace is closely controlled.

Abstract: The present invention is an oven and method of operation for heating thermoplastic articles. Articles are fed into the oven on a conveyor belt. There is a heating plate directly beneath the article bearing surface of the conveyor belt which heats the supported side of the article. The surface of the article not in contact with the belt is heated by conventional means within the oven.

Abstract: Manufacturing of carbon bodies by heating blanks containing pyrolizable substances in a chamber over in which volatile pyrolysis products are formed and decomposed and thermal energy is generated by combustion of fluid fuels inside the chamber. Below a chamber temperature of 600.degree. C. the fuel is burned by supplying a stoichiometric amount of air, and above a chamber temperature of 600.degree. C. an additional quantity of air is blown into the chamber through nozzles.

Abstract: A furnace for heating pipes each having an upset portion at least at one of its opposite ends includes a housing defining a heating chamber filled with high temperature gas, and a conveying apparatus for sequentially conveying the pipes in the housing in a direction perpendicular to an axial direction of the pipes. A blowing device is provided on one side of a path of the upset portion, and a waving plate is provided on the other side of the path, whereby the upset portion, when passing through a space between the blowing device and the plate, is heated locally by the high temperature gas blown out from the blowing device and also by the reflected high temperature gas and radiant heat from the plate.

Abstract: This disclosure is directed to an oxy-hydrogen torch (10) comprised of a plate (16) captured between first and second outer members (12 and 14). Each outer member has a plenum (18) which open towards, and is separated by, the plate (16). The plate (16) has a plurality of groups (29, 30, 31) of spaced grooves (32--32) in one major surface (34). The groups of grooves (32--32) are arranged in an interleaved relationship with groups (29', 30', 31') of spaced grooves (36--36) on the opposite surface (38). The grooves (32 and 36) extend from one surface 46 of the plate (16) to the respective plenums (18--18) in the outer members (12 and 14). Each of the grooves (32 and 36) in a group are radially directed at a different point. Oxygen is directed into one plenum (18) and hydrogen urged into the other plenum. The gases pass through the respective grooves (32 and 36) to the surface (46) of the torch (10) for mixing and ignition.

Abstract: A large scale, industrial system and method for dehydrating fruits, nuts or other produce. The system includes two long air tunnels which are placed end-to-end. Each air tunnel has a conveyor which is used to transport the produce through the air tunnel. As the produce exits one air tunnel, it is dropped from one conveyor onto the other, thus permitting the produce to be turned over before it enters the second air tunnel. Each air tunnel is divided into a number of separate air chambers in which the heated, circulating air is confined so as to reduce heat loss, thus increasing the energy efficiency of the system, and also providing for separate control of the air temperature and humidity levels in each air chamber. Countercirculation of air between adjacent air chambers aids in confining the air through the separate air chambers, as well as the use of resilient flaps which are used to enclose the ends of each air chamber through which the conveyor enters and exits.

Abstract: Metal bodies such as billets and blooms are reheated for rolling in a metal-refining operation having a blast furnace by first heating the top gas of the blast furnace to at least 800.degree. C. by means of a plasma torch, then, before the gas has cooled appreciably, burning the heated top gas in a preheating chamber. The metal bodies are exposed in the preheating chamber to the heat of the burning and heated top gas. The heated top gas is mixed with combustion-inducing gas to burn it. Before it is mixed with the heated top gas it is preheated by heat exchange with combustion-product gas withdrawn from the preheating chamber. In this manner it is possible to raise the temperature of this combustion-inducing gas to at least 600.degree. C., so that the burners firing the preheating chamber burn clean. In addition much of the heat of the process is recovered, again reducing energy costs for the system.

Abstract: Articles--e.g. foodstuffs wrapped in polyethylene bags--to be subjected to heat treatment in a bath of hot water are dropped from an input conveyor into an elongate tank at an inlet end for entrainment by a circulating flow toward an outlet end. A perforated extraction conveyor partly immersed in the water intercepts the entrained articles and lifts them out of the flow onto an output conveyor for drying and subsequent storage. The entering water may be set in vortical motion by convoluted baffles, converging in the flow direction, for insuring full submersion of the articles to be treated.

Abstract: The improvement in a walking beam oil country tube reheat furnace comprises a first row of burners positioned in spaced relationship and transverse the furnace hearth with each of the burners containing a refractory housing positioned in the limited space between the walking beam pass line and the hearth of the furnace. The burner includes a burner body and a centrally disposed fuel tube so as to define an annular air chamber thereabout. The burner includes a 90.degree. bend so as to fire in parallel relationship to the pass line. The method of retrofitting a top fired walking beam furnace includes inserting at least one unitized bung of said spaced burners through the furnace floor and into the space between the pass line and floor and firing the burners in parallel relationship with the pass line.

Abstract: The preform (1) for the production of hollow articles by blow-moulding possesses a profiled false neck (4) provided with a circular toothed collar (6), and during the thermal conditioning of the preform for the purpose of final blowing, the preform, held loosely by idling holding rollers (8) (9) at the level of the profiling of its false neck (4), is caused to rotate about its longitudinal axis by a toothed drive member (13) which cooperates with the circular toothed collar (6).

Abstract: Apparatus is disclosed for heating a plurality of sheets of plastic material between adjacent ones of a plurality of vertically stacked and individually heated platens. The platens are vertically displaceable together and relative to one another, and any two vertically adjacent platens are vertically separable relative to a fixed horizontal pass line to facilitate removing a heated plastic sheet from between the platens and introducing a plastic sheet to be heated therebetween. Vertical separation is achieved by latching the upper one of two adjacent platens in a fixed holding position above the pass line and lowering the lower one of the two platens and any other platens of the stack therebeneath to position the upper surface of the lowered platen at the pass line. Sheet discharge and feed mechanisms are then operable respectively to remove a heated sheet from the lower platen and introduce a sheet to be heated onto the lower platen.

Abstract: A semi-continuous vacuum heat-treating furnace of two-chambers and one-door type is composed of a vacuum heating chamber which includes a heating element and a heat insulation material, both being stable in chemical property and strength in vacuum condition and atmospheric pressure at high temperature, a cooling chamber which is associated with the vacuum heating chamber, and an intermediate vacuum door which separates the vacuum heating chamber and the cooling chamber from each other.

Abstract: A pusher-type furnace for heating slabs is disclosed having lift rails in its soak zone for periodically raising slabs out of contact with skid rails along which the slabs travel through the furnace. The controlled raising and lowering of the lift rails in the soak zone alternates with extraction of slabs from the furnace discharge end and pushing of slabs along the skid rails, and reduces or eliminates soak zone skid marks on the bottom surface of the slabs without the need for a soak hearth. The lift mechanism comprises an open structure of rails and supporting members to facilitate heating as well as soaking of the slabs in the furnace soak zone, thus promoting efficient use of fuel.

Abstract: A furnace (100) is provided which aids in the reduction of polysilicon and quartz contaminants during polysilicon deposition on monocrystalline wafers. The wafers are heated for polysilicon deposition within the interior of a quartz tube (102) which is mounted so that the interior sidewalls are vertical and the tube opening is at the top of the furnace. A quartz boat (104) is adapted for carrying the wafers in a spaced apart relationship with a quartz rod (144) maintaining the wafers within the boat when it is suspended vertically from an elevator bar (128). The elevator bar moves the quartz boat vertically into the interior of the quartz tube (102) for heating without contact between the quartz boat and sidewalls of the quartz tube. The level of contamination is therefore less and the yield of certain integrated circuits much improved.

Abstract: The hearth of the furnace is indexed in such a manner that successive workpieces in a loading position are loaded in non-adjacent stations of the hearth during one revolution and are loaded in intervening stations during one or more subsequent revolutions. The method of loading and indexing the hearth enables a uniform temperature distribution to be more easily maintained in the furnace and provides flexibility in locating an unloading position relative to the loading position.

Abstract: This relates to a heating system and process for reheating preforms prior to delivering the preforms to a blow molder. The heating system utilizes different types of heating units, one of which will heat the preform wall more highly at the interior surface and the other of which will heat the preform wall at the exterior surface. By effectively controlling the heat input to a preform from each heating unit and by controlling the outputs of the different heating units in combination, the desired temperature profile through the preform wall may be obtained substantially without any time in the oven being provided for heat equilibration and at the same time a maximum heating effort may be effected to produce the necessary heating of a preform within a minimal time and more uniformly than heretofore possible.

Abstract: In a pass-through sintering furnace for sintering a succession of ceramic tubes fed lengthwise through the furnace and rotated as they pass through the furnace, the tubes, when heated in the furnace, are kept apart by pushing each tube into the furnace at one end and pulling it out from the other end. The pulling speed is less than the pushing speed to ensure uniform firing throughout the length of the tube, allowing for shrinkage as the tube is fired, but is sufficient to hold the pulled tube clear of the next following tube so as to obviate any pushing against the end of a hot tube.

Abstract: A control method comprises predetermining a or presuming a fuel flow rate for each of three control zones of a continuous slab reheating furnace, predicting each slab temperature after a plurality of time intervals from the presumed fuel flow rate, and controlling the fuel flow rate for each zone so as to minimize the sum of the differences between the predicted temperatures and corresponding objective temperature rise curves for all the slabs. Alternatively, the method may comprise sensing flow rates of the fuel and air for each zone at time intervals .DELTA.t, calculating the temperature profile within the furnace and then the temperature of each slab at the present time point from the sensed flow rates, repeating the calculations with the calculated slab temperature and any presumed fuel flow rate for each zone to predict the temperature profile within the furnace and each slab temperature after .DELTA.

Abstract: A process for firing ceramic bodies, in particular tiles, is disclosed, consisting in conveying the ceramic bodies through an elongated heat treatment chamber, both main faces thereof being freely exposed to heat transmission, simultaneously heating said bodies and the chamber walls by means of a heating fluid, generally combustion gases, the temperature of the portions of the chamber walls which are in view of the ceramic bodies not being higher than that of the heating fluid and controlling the flow of the heating fluid so that its actual volume flow rate, measured axially of the chamber and at the point thereof where the chamber temperature is 900.degree. C., is comprised between 4500 and 12,000, and preferably between 6000 and 10,000 cu.m. per sq.m. of transverse cross-section. Preferably the surface rate of travel of the tiles, when tiles are fired, is comprised between 22 and 30 sq.m. of tile per hour and per linear meter of inner perimeter of the chamber, for 4.5 mm.

Abstract: A temperature controlling method for heating, with a heating furnace having at least one heating zone provided with a controllable heating means, materials charged into the heating furnace such that an aimed temperature of the material is reached by the time when the materials leave the heating furnace. The characteristic feature of the invention resides in that the instructions for changing the operating condition of the heating furnace in response to a change in the rolling condition of the rolling line connected to the heating furnace is treated as a change in the period of stay of the material in the heating furnace. In the controlling system in accordance with the invention, determination of the material temperature rise pattern in response to the change in the staying period of the material in the furnace is made to minimize the supply of fuel to the heating means, and the set temperature of each heating zone is calculated from the thus determined temperature rise pattern.

Abstract: Appropriately spaced aligning pins are engaged with respectively corresponding portions of each of plural saggers disposed on a pallet. The pallet and aligning pins are then moved relative to one another so as to accurately and substantially simultaneously space apart the plural saggers on the pallet prior to firing.

Abstract: For each of three control zones in a furnace, a computer calculates, at time intervals .DELTA.t, the heat input to slabs from the actual flow rates of the fuel and air and other stored data through the use of the equation of the thermal equilibrium and then determining the heat input to each slab by apportioning the calculated heat input among the slabs according to its heat content before the .DELTA.t. Subsequently, the computer estimates the fuel flow rate after the time interval .DELTA.t from a difference between the calculated heat input and an objective heat input and then determining the fuel flow rate through the use of the equation of the thermal equilibrium. For each control zone, a fuel regulator controls the fuel flow rate in response to the estimated flow rate while an air regulator controls an air flow rate in response to an optimum air ratio as determined by the estimated flow rate.

Abstract: A process and arrangement for the continual zonal heating or cooling of perably elongate treatment members within at least one zone extending perpendicular or transverse to the longitudinal axis, which programmatically traverses the treatment member in the longitudinal direction.

Abstract: A method and system is provided for controlling a reheating furnace having entrance and discharge ends, a preheating zone at the entrance end, and heating and soaking zones sequentially adjacent the preheating zone in the direction toward the discharge end, and an exhaust gas flue at the entrance end. The method and control system provides for obtaining an optimum temperature profile through the preheating and heating zones with minimum fuel consumption in connection with operation of the preheating zone by controlling the fuel supply to the preheating zone in accordance with the rate or quantity of fuel flow to the heating zone and the temperature of the exhaust gas from the furnace.

Abstract: An electrophotographic copying machine comprises at least one paper supply unit from which a copying is automatically supplied towards a processing station, a manual feed mouth through which a copying paper is manually inserted into the machine, an electrophotographic processing unit for forming thermally fusible powder image on the copying paper, and a heat-fixing device for fusing and fixing the powder image on the copying paper. This machine is provided with a manual paper feed inhibiting device operable in such a manner the manual feed of the copying paper through the manual feed mouth is permitted only when and after the heat fixing device has attained the predetermined high temperature.

Abstract: An electrographic apparatus by which powder images corresponding to electrostatic images can be formed on receiving material and fixed onto the receiving material by heat and contact is provided with a control system which regulates the quantity of receiving material transported to the fixing device per unit of time so as to keep the heat content of heated surface elements of the fixing device suited for the heat capacity of the receiving material even when receiving materials of different weights are used. The control system can also make the formation of either electrostatic or powder images dependent upon the existance of heat content in the fixing device suited for the heat capacity of the receiving material.

Abstract: A process is described according to which tiles are taken up from the oven in which they have been fired, are accelerated to space them from one another, and then are further accelerated and brought into alignment in a direction transverse to that of travel, and are finally discharged onto a terminal conveyor. The apparatus for carrying out the process comprises, in combination with each firing oven chamber and with a terminal conveyor, a first conveyor for taking up the tiles from the oven, a second conveyor for accelerating them, a third conveyor for ejecting the tiles onto the terminal conveyor, and means for aligning the tiles with respect to the direction of travel of this latter before they leave the ejecting conveyor. The speeds on the accelerating conveyor and on the ejecting conveyor for high speed ovens, are respectively 1.8 to 2.2 times and three to five times the linear speed of the tiles in the oven.

Abstract: An improved conveyor assembly is provided for transporting a transparent vitreous substrate along a group of controlled radiative heaters. A plurality of control groups are formed from the radiative heaters and the illumination for the various control groups is isolated so that areas of the conveyor or substrate are illuminated by only a single control group at any one time. Heater control thermocouples are affixed to the radiative heater elements and the output signals from the control thermocouples are calibrated from a calibration thermocouple extending to a position between the control thermocouple and the substrate surface. A wire mesh belt assembly permits illumination of the substrate through the conveyor assembly while supporting the substrate in a manner effective to obtain uniform heating of the substrate.

Abstract: This invention relates to a method of controlling the temperature of a heating furnace which has at least one furnace zone capable of being controlled by heating means and which conveys materials to be heated, that are introduced thereinto, by conveyor means such as a walking beam or a pusher so that the materials are heated to a predetermined temperature until they are withdrawn from the discharge side.More specifically, the present invention relates to a method of controlling set furnace zone temperature of the heating furnace when the materials to be heated, that are introduced into the heating furnace, have different temperature elevation patterns. The method of the invention is specifically characterized in that the predetermined set temperatures of each zone is used when the temperature elevation patterns of slabs are different with each other.

Abstract: A method for controlling, in a reheat furnace of the type having a heat zone through which metal work pieces are moved over support skids and a soak zone in which slab temperature differentials are reduced, the variations in deformation resistance of the workpiece due to temperature gradients produced by the skids. This method first provides for establishing, for the furnace and the workpiece to be rolled, an initial skid mark characteristic expressing, at the time the workpiece leaves the support skids and enters the soak zone, the ratio of the deformation resistance of the workpiece in a region immediately contiguous the skids to the deformation resistance of the workpiece in a second region which is located approximately mid-way between adjacent skids. A skid mark decay characteristic defining the decay of the skid mark characteristic as a function of time elapsed after the workpiece has left the skids is then established.

Abstract: A method and apparatus for condensation heating. Articles to be heated are conveyed into a heating chamber which is filled with vapors of a fluid having a relatively high boiling point. When the vapors contact the article to be heated they condense thereon and transfer the latent heat of vaporization, thus heating the object. Vapors escaping from the heating chamber are trapped by flows of carrier gas at the inlet and outlet of the heating chamber. The carrier gas, which is thus partially saturated with vapor, is channeled into a gas/vapor separator wherein the vapor is extracted and recycled back to the heating chamber.

Abstract: A method and an apparatus for the heat treatment of a float glass ribbon in which a tunnel lehr is provided with arrays of parallel heat-exchange tubes above and below the path of the ribbon and for each of the longitudinally divided zones of these arrays, the tubes are grouped and provided with respective heaters at the upstream end of the zone while all of the tubes at the zone are connected to a flow at the downstream end for drawing the heated air through the tubes. The temperature of the glass ribbon is measured at the upstream end and the throughflow of the individual groups is controlled selectively to ensure a homogeneous temperature distribution in the glass ribbon.