Abstract: The invention is direct to a method and an apparatus for the bulk determination of scrap metal content, said method comprising the steps of providing a scrap metal input; preparing said input for submission to a bulk scanning apparatus; scanning at least part of the scrap metal with a bulk scanning apparatus to determine the composition of the scrap metal; and securing said scrap metal from the step of providing the scrap metal input to the step of scanning at least part of the scrap metal. Said apparatus comprises a scanning container together with a low-intensity neutron scattering device, a laser cutting device and/or magnetic sensing device.

Abstract: A method includes obtaining data associated with operation of equipment in an industrial process and identifying training data and evaluation data in the obtained data. The method also includes, during each of multiple training periods, identifying one or more models and one or more first statistical values using at least some of the training data and determining a threshold value using the one or more first statistical values. The one or more models represent the operation of the equipment. The method further includes, during each of multiple evaluation periods, determining one or more second statistical values using at least some of the evaluation data and the one or more models, comparing the one or more second statistical values to the threshold value determined in a preceding one of the training periods, and determining whether the equipment is suffering from at least one specified condition based on the comparison.

Abstract: The invention relates to an optical monitoring system (26) for monitoring operating conditions in a tuyere zone of a blast furnace. This system comprises a light deflecting device (40) with a peep sight (28) arranged in a first face (46) of the light deflecting device (40) and an optical sensor (30) arranged in a second face (48) of the light deflecting device (40). A light deflector (41) is arranged within the light deflecting device (40) for directing incident light from the tuyere zone towards the peep sight (28) and towards the optical sensor (30). The light deflecting device (40) comprises a housing (56) with a spherical body (60) rotatably arranged therein.

Abstract: A quenching tank system includes a cooling tank having an entrance opening adapted to allow a first portion of a heated continuous tube to enter the cooling tank and to allow a first portion of a cooling fluid in the tank to flow out the entrance opening. The cooling tank includes an exit opening adapted to allow a partially cooled second portion of the continuous tube moving through the tank to exit the cooling tank and to allow a second portion of the cooling fluid in the tank to flow out the exit opening. The system also includes a cooling fluid collection and distribution system adapted to collect cooling fluid flowing out of the cooling tank, return the collected cooling fluid to the cooling tank and distribute the cooling fluid in the cooling tank. A method of cooling a heated continuous tube using a quenching tank system is described.

Abstract: A Ruhrstahl-Heraeus (RH) apparatus for performing a vacuum degassing process of molten metal includes a sensor hole formed at a lower vessel of a vacuum vessel; a continuous temperature measuring device mounted on the sensor hole and including a light-to-temperature converter measuring temperature based on received light, a light guide rod receiving light from a measurement target, an optical fiber transferring the light received by the light guide rod to the light-to-temperature converter, a connector connecting the optical fiber to the light guide rod while maintaining straightness of the optical fiber, a primary protection tube enclosing an outer peripheral surface of the light guide rod, a flexible heat resistant tube protecting the optical fiber, and a joint connected to the flexible heat resistant tube and provided with a cooling gas injection tube; and a cooling gas supply unit supplying cooling gas to the cooling gas injection tube.

Abstract: Apparatuses, methods, and systems are disclosed for the characterization of the integrity and profile measurement of a caster mold by use of a scanning device, a positioning fixture, and a data reduction device connected to the scanning device, the data reduction device being configured to characterize the integrity and to measure the profile of the caster mold by comparing scanned distances to reference distance values.

Abstract: A burner for a flash smelting furnace. The burner includes an injector having a sleeve for delivering pulverous feed material to the furnace and having a central lance within the sleeve to supply compressed air for dispersing the pulverous feed material in the reaction shaft of the furnace. The central lance has an annular slot at its tip for creating a substantially continuous air curtain.

Abstract: Embodiments of the present invention relate to automatic sanding hopper systems and methods for supplying sand to a tap hole in a furnace. The automatic sanding hopper system may automatically open a chimney door to provide access to a furnace through a chimney hole. A hopper assembly in the sanding hopper system may automatically move to a position in which a plunger may automatically actuate to clear or clean out the chimney hole. The hopper assembly may thereafter automatically move to a position in which a sand dispenser delivers sand through the chimney hole, into the furnace, and into the tap hole in the furnace. A sensor device may determine whether or not the tap hole is properly filled with sand. The hopper assembly may automatically retract and the chimney door may automatically close to begin another steelmaking heat.

Abstract: A resident measurement system for a charge level of a blast furnace includes a chamber, a servo system, a distance measurement unit, and a cooling-cleaning unit. The chamber is combined with a lateral furnace wall of the blast-furnace, covers an opening of the furnace wall, and has a pivoting hole. A pivot of the distance measurement unit is pivotally disposed at the pivoting hole, and the distance measurement unit is driven by the servo system to perform a motion with the pivot as a movement center, so as to measure the charge level. The cooling-cleaning unit is used to supply a high-pressure gas, which flows through the distance measurement unit to perform cooling and cleansing operations.

Abstract: A burner for a flash smelting furnace. The burner includes a distributor for receiving pulverous feed material from a plurality of feed pipes. The distributor has at least one curved deflector that directs the feed stream in an evenly distributed annulus into the sleeve of the burner.

Abstract: A burner for a flash smelting furnace. The burner includes an injector having a sleeve for delivering pulverous feed material to the furnace and having a central lance within the sleeve to supply compressed air for dispersing the pulverous feed material in the reaction shaft of the furnace. The central lance has an annular slot at its tip for creating a substantially continuous air curtain.

Abstract: The main objective of the present invention is to provide maintenance mechanism for lighting equipment in a closed space of high radiation activity, which comprises a passage, a lamp base, a multi-section slide rail, a lighting handle, a stainless steel fixation plate, a lead glass lamp guard and a convex lead plug. On the top side of the passage there is a multi-section slide rail with the lamp base attached to move the lamp. The maintenance hole at the end of the passage has a convex lead plug and a stainless steel fixation plate. When the hole closes, the convex lead plug is locked to the lead plug positioning screw under the stainless steel fixation plate; while the maintenance hole opens, on the top right and top left of the stainless steel fixation plate there is a L-shaped short iron plate and a L-shaped long iron plate respectively. On the L-shaped long iron plate there is an axial screw as the axis for the convex lead plug to move and rotate.

Abstract: A steel production facility and a method of uninterrupted, or at least cyclical, steelmaking in the facility. In the case of uninterrupted steelmaking at least the first three of the following steps and in case of cyclical steelmaking all five steps are performed: charge materials are molten uninterruptedly or cyclically in an electric arc furnace; the charge materials (e.g.

Abstract: A system and method for measuring the inner space of a container provides for the measurement of the wear of the lining of a container such as a torpedo ladle optionally while the ladle is still hot. The interior lining of the container is scanned by a scanner head from a first position in the container which is at an angle relative to the vertical axis of the container. The scanner head is placed in a second position in the container at an angle relative to the vertical axis of the container and from the second position the scanner head scans the portions of the interior lining of the container which were not scanned during the first position scan. By comparing the scanning measurements of the lining from the first position scan and the second position scan after the container has been loaded and unloaded with an initial reference measurement of the lining the wear of the lining can be measured.

Abstract: An apparatus for observing the interior of a blast furnace system includes a visible light guiding unit which defines a light path along a viewing axis that is radial to an upright axis of a furnace wall body of a blast furnace and which is adapted to be secured to a furnace blowpipe to permit the light path to be in visual communication with a tuyere, a beam splitter which is disposed in an accommodation space in the tubular mount to split a beam of light propagating along the light path into a horizontal component so that the operator can observe furnace condition through a peeping hole, and a vertical component, and a video camera system which includes an elongate casing connected to the tubular mount, and a video camera disposed in a cooling chamber of the casing to capture a light image from the vertical component of the light beam.

Abstract: A smelt spout area of a recovery boiler. A bank of smelt spouts is connected to a lower part of the boiler for directing smelt from the boiler to a dissolving tank. A working area is in front of the bank of smelt spouts. A shielding wall is located in front of the bank of smelt spouts and arranged movable in relation to the bank of smelt spouts to separate the bank of smelt spouts from the working area and persons working on the working area.

Abstract: A water-cooling jacket structure 10 for an inspection hole of a flash furnace 1 is arranged at the periphery of a concentrate burner 7 to inspect and clean the inside of the furnace and the concentrate burner 7, and formed in a cylindrical shape by combining a plurality of jacket plates 11, 12, 13, 14 cast internally with cooling tubes 21, 22, 23, 24 for circulating cooling-water, and configured to adjust its cooling capacity and amount of cooling-water by circulating cooling-water to a single or multiple systems of the respective cooling-water systems of each jacket 11, 12, 13, 14 depending on the heat-load of the flash furnace 1.

Abstract: An inspection hole structure 1 forming a furnace inspection hole 2 installed on the reaction shaft ceiling 104 of a flash smelting furnace, comprising a lower-stage water-cooling jacket 3A having an opening 3Aa at the center; an upper-stage water-cooling jacket 3B which is connected integrally to an upper part of said lower-stage water-cooling jacket 3A and forms said inspection hole 2 at the center in cooperation with said lower-stage water-cooling jacket 3A; and a bottom cover water-cooling jacket 4 provided in said lower-stage water-cooling jacket 3A to open or close said opening of said lower-stage water-cooling jacket 3A.

Abstract: An apparatus for observing the interior of a blast furnace system includes a visible light guiding unit which defines a light path along a viewing axis that is radial to an upright axis of a furnace wall body of a blast furnace and which is adapted to be secured to a furnace blowpipe to permit the light path to be in visual communication with a tuyere, a beam splitter which is disposed in an accommodation space in the tubular mount to split a beam of light propagating along the light path into a horizontal component so that the operator can observe furnace condition through a peeping hole, and a vertical component, and a video camera system which includes an elongate casing connected to the tubular mount, and a video camera disposed in a cooling chamber of the casing to capture a light image from the vertical component of the light beam.

Abstract: Methods for treating aluminum in a furnace. An aluminum charge is introduced into a furnace and melted with heat from at least one burner. The burner is supplied with at least one oxidizer and at least one fuel. The oxidizer is made up of at least 10% oxygen by volume. The concentration of a first gas is measured in the furnace atmosphere or in a flue gas exiting the furnace. The oxidation of the molten aluminum is then reduced by holding the flow rate of the oxidizer steady while varying the flow rate of the fuel, according to the concentration of a second gas in the furnace or in the flue gas exiting the furnace. The concentration of the second gas is determined by comparing the measured species concentration and the intrinsic concentration which would be present absent the aluminum charge.

Abstract: The present invention relates to an industrial furnace for smelting metals, in particular nonferrous metals, and the respective nozzle element.

Abstract: An inspection hole structure 1 forming a furnace inspection hole 2 installed on the reaction shaft ceiling of a flash smelting furnace, comprising a lower-stage water-cooling jacket 3A having an opening 3Aa at the center; an upper-stage water-cooling jacket 3B which is connected integrally to an upper part of said lower-stage water-cooling jacket 3A and forms said inspection hole 2 at the center in cooperation with said lower-stage water-cooling jacket 3A; and a bottom cover water-cooling jacket 4 provided in said lower-stage water-cooling jacket 3A to open or close said opening of said lower-stage water-cooling jacket 3A.

Abstract: The invention relates to a metallurgical vessel (1), particularly a converter (2), with support consoles (10) arranged on the wall (3) of the vessel. Said consoles are fixed to a support body (4) that does not fully surround the periphery of the vessel by means of a fixing system (9) which comprises clamping means (12) that engage with the support consoles (10) and can be pivoted into and out of a position of engagement. The vessel (1) can be removed from the support body (4) and can be reconnected therewith when the clamping means (12) are not in a position of engagement. According to the invention, the clamping means (12) comprise a clamping lever (13) which is engaged on one side and which describes a pivoting movement by means of a hydraulic pressure unit (17).

Abstract: A flange (1) for optical flame observation in a gas turbine includes at least one bore for optical observation, in which bore there is arranged at least one pane (9, 10) for separating the flame-side space, which is in substantially direct communication with a combustion chamber in which the at least one flame that is to be monitored is arranged, from the outside space, from which the observation of the at least one flame can take place. In a flange (1) of this type, fogging of the at least one pane (9, 10) is made possible in a simple manner which can be guaranteed over a prolonged period of time by virtue of the fact that two panes (9, 10), which delimit a sealed intermediate space (22) in the bore for optical observation, are arranged one behind the other with respect to the optical axis (8), and that a device (24) for dehumidifying the sealed intermediate space (22) is includes.

Abstract: The invention provides a cooling system for protecting an image fiber and an imaging device from thermal influences and a temperature measurement apparatus, for a molten metal, capable of being easily controlled and stably measuring the temperature. The temperature measurement apparatus for a molten metal comprises four connectable portions of a nozzle portion a purge/cooling gas introduction portion, an image fiber fitting portion with a window glass and an image fiber to a double pipe nozzle protection tube. A distance from a nozzle distal end as an introduction portion of thermal radiation light to a light reception portion at an image fiber distal end becomes short so that a greater amount of thermal radiation light can be received.

Abstract: In accordance with one aspect of the disclosure, a method of sensing the temperature of a molten metal vehicle is provided. In one exemplary embodiment, the method includes utilizing at least one thermal imager located to the side of the molten metal during the dispensing of the molten metal and capturing at least one thermal image for determining the rotational position of the molten metal vehicle by calculating an area of the molten metal.

Abstract: A system for optically analyzing a molten metal bath wherein a high velocity gas stream is passed from a lance to the bath and is maintained coherent by a flame envelope to provide a clear sight pathway through the gas stream for sighting the molten metal bath longitudinally through the gas stream from a remote or spaced sighting point.

Abstract: An improved method and apparatus for recovering metal values from Electric Arc Furnace dust, particularly zinc and iron values, by mixing EAF dust and carbonaceous fines to form a particulate mixture; heating the mixture at a sufficient temperature and for a sufficient time to reduce and release volatile metals and alkali metals in a flue gas; collecting the released metals, and removing the metal values from the process as product.

Abstract: A method for representing slag in a molten metal stream is disclosed, comprising the steps of obtaining and storing digital images of the molten metal stream, identifying areas of similarity on the basis of texture and intensity, defining a subset of those areas, comparing at least one selected property of the subset against a defined parameter and generating an output signal on the basis of the comparison, wherein the output signal is indicative of the presence or absence of slag. Also disclosed is a system for carrying out the above method and visually displaying the resulting output signals to facilitate operator analysis of the results. The system allows use of inexpensive optical equipment in place of an expensive infrared detection apparatus.

Abstract: The present invention is directed to an oxygen lance crane assembly that includes a measuring device positioned to take measurements to a target area within a BOF vessel. The measuring device includes an optical head for receiving and directing an energy beam to the target area within an associated metallurgical vessel, and for receiving and directing a reflected energy beam to a processor that converts the reflected energy beam into a distance measurement. A drive means, provided within a housing fastened to the lance crane assembly, is attached to the optical head so that when the drive means is operated the optical head is either extended through an opening in the housing to a remote measuring position at a line of sight to the target area within the metallurgical vessel, or retracted back through the opening to a stored position within the housing.

Abstract: An apparatus and method for reclaiming contaminated scrap metal, more particularly an improved reverberatory furnace designed for melting scrap. The amount of hydrocarbons volatilized from the melting of contaminated scrap is measured and the fumes are passed into the main hearth for burning. As the amount of fuel value contained within the fumes increases, the amount of fuel provided to the burner is proportionally reduced while the amount of oxygen is kept constant. This will ensure that the amount of fuel and the amount of oxygen present within the furnace is completely burned without excessive free oxygen or unburned fuel building up within the furnace or furnace exhaust. The burner will be operating under lean fuel conditions or under fuel rich conditions such that the flame temperature is lower than at stoichiometric firing, whereby the burners create reduced NOx.

Abstract: A method and an apparatus for monitoring and controlling the quality of the galvannealed coating of steel strip immediately following the galvannealing step, wherein the hot galvanized coating of the steel strip produced by hot dipping is converted into FeZn phases by diffusion reactions through a thermal treatment in an annealing furnace at temperatures above the melting point of zinc. The measurement value used for the quality of the galvannealed coating of the steel strip is the visual appearance of the galvannealed coating recorded by a visual recording device in the form of measurement signals as the quality measurement value, wherein the measurement signals are processed by measurement technology and the resulting measurement values are used after conversion into control variables for the direct control of the annealing furnace.

Abstract: A flame detection system for detecting blockage in oil injection paths into blast furnaces utilized in the manufacture of iron. The flame detection system, as designed and installed, monitors the amount of light seen through a blowpipe peephole and causes an alarm to be actuated when a voltage falls below a predetermined threshold thereby indicating that the amount of light being received by a photocell mounted at the peephole is at a low enough level to possibly indicate injection path or port clogging. Efficient calibration circuitry and techniques are also provided.

Abstract: An apparatus and method for viewing and analyzing the interior of a molten metal bath during treatment in a metallurgical vessel comprises a concentric pipe tuyere extending into an open mouth of the vessel and below the surface of the bath and comprising an inner pipe through which a pressurized transparent fluid is passed, and an outer pipe forming, with the inner pipe, an annulus through which a cooling fluid is passed. A sight glass is disposed in alignment with an opening in the inner pipe and with a centerline of the tuyere providing visual access to the interior of the bath. An optical sensor is associated with the sight glass to receive and analyze light generated in the bath to determine molten metal properties such as temperature and chemical composition.

Abstract: An on-line system for measuring the composition of scrap metal, including a loader with a load sensor having a motion compensator linked to a bulk material analyzer such as a prompt gamma-ray neutron activation analyzer. The grade of scrap used to prepare batches for a melt is controlled to provide a batch having desired properties and composition.

Abstract: An apparatus and method for viewing and analyzing the interior of a molten metal bath during treatment in a metallurgical vessel comprises a concentric pipe tuyere extending into the vessel below the surface of the bath and comprising an inner pipe through which a pressurized transparent fluid is passed, and an outer pipe forming, with the inner pipe, an annulus through which a cooling fluid is passed. A sight glass is disposed in alignment with an opening in the inner pipe and with a centerline of the tuyere providing visual access to the interior of the bath. An optical sensor is associated with the sight glass to receive and analyze light generated in the bath to determine molten metal properties such as temperature and chemical composition.

Abstract: Vortex melting furnace facilities picks up an image of molten slag flow in a direction traverse to the molten slag flow discharged from the furnace, calculates a molten slag flow rate by brilliance discrimination of the image pick-up signal and controls a water feed rate of a molten slag wet granulation and granulated slag dewatering apparatus and a flow rate of the molten slag in the vortex melting furnace. A video camera is arranged such that a direction of image pick-up traverses to a direction of the molten slag flow and the resulting image is brilliance discriminated by a high brilliance area for the molten slag and a low brilliance area for a molten slag conduit, and the high brilliance area is converted to the fusion flow rate from a liquid level of the molten slag in the fusion conduit.

Abstract: A sensor dropper for storing, shielding and dropping sensors into a BOF vessel. The sensor dropper includes a support frame to move the stored sensors toward or away from a sensor drop path leading into said BOF vessel, a dropper assembly supported on the support frame for storing and releasing sensors into the sensor drop path to the BOF, and a shield gate to protect the sensor dropper and stored sensors from BOF fume. The dropper assembly includes a plurality of storage and release mechanisms and corresponding shear mechanisms. Each storage and release mechanism includes a threaded sensor support shaft from which a stored sensor is suspended and dropped into the sensor drop path when the threads of the sensor support shaft are rotated in an outward direction, and each shear mechanism includes a shear blade housed within a tubular cutter having outer shear blades to sever an electrical sensor cable when the inner shear blade is rotated past the outer shear blades.

Abstract: An impact pad for use in a ladle for molten metal comprising a body of refractory material having a lower portion shaped to fit in a ladle and a tapered upper portion having corrugations at the top, the lower portion being grooved around its periphery and having refractory bricks of contrasting color with respect to the refractory material of the body embedded in the body, adapted to be exposed on wearing away of the body.

Abstract: An incineration kiln of the slagging mode, which has an outer shell and a protective layer inside the shell with quantum failure identifiers. The quantum failure identifiers recognizes one or more stages of increasing degree of failure of the protective layer, so that an operator may be warned and take suitable measures to protect further deterioration of the protective layer and restore the same.

Abstract: An apparatus, system and method for viewing an industrial process in an obscuring environment, such as molten metal atomization, is disclosed. An enclosure defining a chamber for containing a particulate form from atomized liquid metal has a nozzle for atomizing liquid metal mounted thereon in communication with the chamber whereby particles recirculate throughout the chamber. The nozzle being comprised of a cylindrical plenum means and a melt guide tube extending axially therethrough to an exit orifice. The plenum means is configured to provide a jet of atomizing gas converging in an atomizing zone extending from the exit orifice. A viewing means extends through the enclosure to a viewing orifice adjacent the atomization zone, the viewing means being configured to extend a field of view through the chamber to the atomization zone.

Abstract: A temperature probe is disclosed for determining the temperature at which residual oils can be vaporized from cold rolled strip without producing free carbon. The probe includes an open ended first tubular member with a burner mounted at one end of the first tubular member for closing the end thereof so that the burner fires its products of combustion through the first tubular member and out the other end thereof. A closed end second tubular member concentrically receives the first tubular member to define an annular heat space therebetween and has an exhaust port in fluid communication with said annular heat space adjacent the burner.

Abstract: A device, e.g., a stirring plug or a mono-block stirring plug and pocket block set, for introducing gas into a mass of molten metal. The devices each have a body formed of a first refractory material. The stirring plug has plural V-shaped, gas carrying slots extending therethrough, while the mono-block set includes plural helical passageways extending therethrough. A wear indicator comprising a thin walled, thermally insulative tube having a central core of a second refractory material of a different coefficient of light emission but similar coefficient of thermal expansion to the first material is disposed within a central recess in the body adjacent either the top or the bottom end of the device. The wear indicator extends towards an intermediate point representing the remnant height of the device.

Abstract: An improved cell for removal of silver ions from a liquid such as used photographic fixer includes a container having enclosed side and bottom walls. Fluid flow inlets and outlets for the flow of a liquid into and out of said cell are provided at opposite ends of the container. A layer of iron-containing material is positioned between the inlet and the outlet, and a layer of pellets, preferably spherical, having a density greater than water, is positioned above the layer of iron-containing material so that the iron-containing material is continuously compressed by the weight of the pellets, thereby avoiding formation of voids in the material as it is consumed.

Abstract: A peepsight for a blast furnace tuyere sensor system comprises a housing in which is mounted a colored glass viewing window and one end of a fiber optic cable directed toward a tuyere so that an operator can view the interior of the furnace and the cable can receive light energy emitted at the tuyere for transmittal of such light energy to an optical sensor.

Abstract: A gas stirring plug for introducing gas into a mass of molten metal. The plug is a generally frusto-conical shaped member which is worn away during use and which should be replaced when it has worn away to a predetermined point and comprises a shell, a core, and a low melting point component disposed within a cavity in the core. The core is located within the shell and is comprised of a refractory material extending between the bottom end and the top end of the plug. The cavity is of a predetermined height and has a bottom located a first predetermined distance above the bottom end of the plug. The cavity is filled with the low melting point component, e.g., soapstone, calcium silicate, talcum, or some other material having a melting point lower than steel, from its bottom to an intermediate point located a predetermined height above the bottom of the cavity. Mortar or some other high melting point refractory component is disposed in the cavity from the intermediate point to the top of the plug.

Abstract: A refractory gas permeable injection device for introducing gas into a metallurgical vessel containing molten metal has a surface to be exposed to and progressively worn away by the molten metal during operation of the vessel. The device includes an outer body and an inner body within the outer body, at least the inner body being formed of a fireproof refractory material. A gas permeable space extends through the device in the direction of wear thereof, and the space has a plurality of different geometric shapes spaced in such direction. Upon the metallurgical vessel being emptied, and with the device still relatively hot, gas is caused to flow through the space such that the gas will create on the surface an optically recognizable image in a particular geometric shape as a function of the relative degree of wear of the device.

Abstract: The invention relates to a device for the detection with measuring techniques of the temperature course of a metal or metal alloy melt in a container (39) which is influenceable by a heating device (22 to 24) and a cooling device (33). The temperature course is herein detected via a thermal camera (49) which is directed toward the region of the solidification front (48) of the melt. The data supplied by the thermal camera (49) are used for the purpose of determining the thermal gradient along on a coordinate of the container (39) and to control the heating device (22 to 24) according to the thermal gradient. Moreover, the data supplied by the thermal camera (49) are used for the determination of the solidification velocity of the melt to regulate the cooling device (33) in accordance with this solidification velocity.

Abstract: The torch fitted with a nozzle (6) comprises a visual observation optical device having one end part coaxially inside the central gas feed pipe (7) and the other end extending outside the body (1) at the opposite end to the nozzle; the optical device being situated a specific distance from the main orifice (17) of the nozzle so that the bounds of its angle of view pass through the edges of said main orifice.

Abstract: A method and apparatus for determining the correct temperature of a heated coil of sheet material and for using said measurement to control a heat treating furnace. The method includes providing a spot of heat resistant material having a known and constant emissivity that is substantially unity on an uneven edge of the coil, the material of the spot remaining on peaks of the uneven edge. The constant emissivity of the spot is independent of that of the edge, the emissivity of which changes and indicates a temperature is substantially different from the true temperature of the edge. The coil is heated and the spot emits infrared energy in an amount that is substantially representative of the correct temperature of the coil and edge. This infrared energy is sensed by an infrared detector aimed at the spot, the output of the energy being indicative of the true temperature of the edge and of the coil mass after it attains the temperature of the edge.