Abstract: A method and apparatus are described for controlling the rate of pouring of molten metal. Examples are given of pouring metal onto a steel strip to form a coating having a uniform controlled thickness thereon. The method comprises the use of an intermediate holding dish having pouring means in the form of a generally vertical slot. The metal head presented to the slot is variable in response to signals from sensors measuring, for example, total strip thickness and the metal level within the holding dish. Signals from the sensors are also used to generate control signals to vary the rate of pouring from a holding furnace into the dish.

Abstract: A method for controlling a flow rate of gas for prereducing ore comprises the steps of prereducing ore in a prereduction furnace having a fluidized bed with a gas generated in a smelting reduction furnace and controlling a pressure of gas generated in the smelting reduction furnace and introduced into the prereduction furnace, thereby controlling the actual flow rate of gas introduced into the prereduction furnace. An apparatus for controlling a flow rate of gas for prereducing ore comprises a flow passage for introducing gas generated in a smelting reduction furnace into a prereduction furnace and a gas pressure control valve positioned in the flow passage.

Abstract: A process and apparatus for producing a spray of atomized metal droplets includes providing an apparatus that forms a spray of molten metal droplets, the apparatus including a metal source and a metal stream atomizer, producing a stream of liquid metal from the metal source, and atomizing the stream of liquid metal with the metal stream atomizer to form the spray of molten metal droplets. A controlled spray of atomized metal droplets is achieved by selectively varying the temperature of the droplets in the spray of molten metal droplets, the step of selectively varying including the step of varying the flow rate of metal produced by the metal source, responsive to a command signal, and sensing the operation of the apparatus and generating the command signal indicative of the operation of the apparatus. The step of atomizing may be accomplished by directing a flow of an atomizing gas at the stream of liquid metal, and then selectively controlling the flow rate of the atomizing gas.

Abstract: Increased cooling rate of an article heated to an elevated temperature is achieved by flowing an inert gas mixture of helium and another inert gas over the article under conditions of turbulent flow.

Abstract: A probe (14) comprises a tubular electrical conductor (15) supported by a sleeve of insulating material (16). The two ends of the conductor are connected to couplings (23, 24) for the circulation of a reducing gas through the entire length of the conductor, as well as to an electric circuit (20) kept at a constant voltage and hence permitting measurement of the resistance in a segment (15c) of the conductor which is exposed to the atmosphere of a furnace, the resistivity of the segment varying as a function of the carbon content of the wall of the conductor.

Abstract: An annealing treatment in a continuous furnace in which a flow of dense inert gas is injected in a rising duct and a descending duct, these flows being regulated by the analysis of hydrogen detected by a pressure controller acting on valves to achieve a minimum escape of hydrogen.

Abstract: In a method to determine disturbances when pouring molten metal from a container having an outlet channel, vibrations generated by the molten metal flowing from the container are measured at parts of the outlet and deviations from a desired vibrational characteristic are determined. From these vibrations disturbances such as blockages in the outlet channel, vortexes and, above all, the outflow of slag can be detected. With this method the reliability of the pouring process can be significantly increased.

Abstract: A torsion pendulum apparatus and a dialometer are combined for simultaneous measurement of the internal friction and the expansion of an alloy. The combination is controlled by a programmable controller so as to conduct in-situ measurements of the internal friction and the expansion of a metal during its phase transformation or specific heat treatment. The results of the internal friction measurement and the expansion measurement can be checked and assumed by one another so that more accurate and detailed information can be obtained for the study of metal alloys.

Abstract: Method and apapratus for inhibiting stress corrosion cracking adjacent weldments in steel workpieces such as stainless steel pipe through generation of a controllable throughwall temperature differential by exposure of one workpiece surface to extermally generated radiant heat while maintaining a flow of coolant fluid past the other surface thereof.

Abstract: A system for automatically or semi-automatically controlling the operation of a tuyere puncher comprises a distance measuring device which measures the distance of the puncher from a reference position, and a programmable device having a memory which may be used to store the position of each tuyere relative to such reference position, the capability of communicating with the distance measuring device to obtain the current puncher position, input capability to read signals from external devices, output capability to control indicating devices and the movement and punching operations of the puncher, and the calculating facility to determine the motion of the puncher to punch all possible punchable tuyeres.

Abstract: Inference is carried out through intermediate hypotheses representing physical states of a blast furnace using HG (Heuristic Grade) in order to comprehensively diagnose the state of the furnace to ascertain optimum actions. Specific parameters are monitored to immediately recognize a transition of conditions inside the furnace to additionally execute the inference. Various types of actions such as defensive actions and offensive actions are covered in this inference. A burden distribution estimation model considering collapse of a coke bed is used for calculating distribution inside the furnace to aid in deciding on an optimum action when an action to alter distribution in the furnace is required as the result of the inference. Creation and alteration of a knowledge base for the inference are carried out without interrupting the inference.

Abstract: A method and apparatus for cooling samples of hot rolled steel sections. A programmable controller directs a predetermined sequence of air and cooling water sprays against the sample while held in a closed container. The controlled cooling of the sample prevents dimensional distortion of the sample so that accurate measurements of the finished hot rolled steel section can be determined.

Abstract: Pyrogenic processes in which gas or fume is evolved are monitored by impinging a beam of X-rays (3) from an X-ray source (1) on the gas or fume whereby radiation is produced by the X-ray fluorescence which is detected by a radiation detector (7) and analyzed by an analyzer (8) for the various constituent elements. In this way the progress of the metallurgical process can be monitored and the information used for process control.

Abstract: Method and apparatus for recovering a metal from an ore by kinetic metallurgy as distinct from the usual static blast furnace approach.

Abstract: A device for monitoring the level of molten metal in a converter comprises a .gamma.-radiation source, a .gamma.-radiation receiver connected to an input of an amplifier connected to a pulse amplitude analyzer, a timer, a molten metal level data display unit. The device for monitoring the level of molten metal in a converter also comprises a processor, a converter position transducer, an oxygen lance position transducer. The inputs of the processor are connected, respectively, to the pulse amplitude analyzer, to the timer, to the converter position transducer, and to the oxygen lance position transducer. The processor outputs are connected to the molten level data display unit and to the timer respectively.

Abstract: A method of monitoring a heating cycle of an induction heating system wherein an inductor encircles a metal workpiece and an alternating current is applied through the inductor from a power supply during the heating cycle. This method comprising the steps of generating an analog signal representative of the voltage across the inductor, as the voltage varies during the heating cycle by changes in the electromagnetic characteristics of the workpiece as the workpiece is being heated; digitizing the voltage representative analog signal; creating a trace of the digitized voltage representative analog signal, with the trace being indicative of the electromagnetic characteristic of the workpiece as sensed by the inductor voltage during the heating cycle; and, comparing the created trace with a preselected pattern.

Abstract: This invention relates to a method and apparatus for reducing iron oxide to metallic iron, utilizing a continuous process employing a reducing gas with high hydrogen and carbon monoxide content made by a catalytically reforming mixture of hydrocarbons, reacted off-gases from the reduction process and steam generated from waste heat from the process and or flue gases. Carbon dioxide and water vapor present in the reacted off-gas is utilized as a hydrocarbon reforming oxidant. Steam generated from waste heat from process and/or waste flue gas is also used as a hydrocarbon reforming oxidant. The steam injected into the process gas stream is also used to control the hydrogen-carbon monoxide ratio required for efficient reduction of iron oxide to metallic iron.

Abstract: An annealing operation is performed with controlling tension force to be exerted on a metal strip depending upon thermal crown of hearth rolls. The thermal crown magnitude is assumed based on various factors influencing for the magnitude of the effective crown.

Abstract: A method for controlling heat conditions in a blast furnace wherein the heat conditions are inferred and judged in comparison of data output from sensor means provided for the blast furnace with knowledge base means formed by accumulated experience on the operation of the blast furnace. The heat conditions are inferred and judged from levels of heat conditions and from levels of transition of heat conditions, wherein data regarding molten metal temperature and those regarding sensors are used. The inference and judgement are carried out by inference engine means included in a small-scale computer.

Abstract: A method and apparatus for measuring the bulk temperature of a workpiece in a quenching apparatus. The temperature is calculated by monitoring the change in size of the bore in the workpiece.

Abstract: The invention concerns an apparatus for studying quenching fluids and quenchability of materials in the form of testpieces 5, comprising a heating furnace, a means for introducing each testpiece into the quenching liquid and extracting the quenched testpiece, a quenching tank 20 containing the quenching fluid and a means for circulating the quenching fluid. According to the invention, the quenching tank 20 comprises an upper tank 21 and a lower tank 22 connected by a means 27 for organizing the circulation, the upper tank being provided with an immersed injector 40 formed by at least one circular array comprising a plurality of radial nozzles and connected to a pressurized fluid source 30, the upper part of the upper tank comprising a conduit 39 for returning the fluid to the pressurization means 30, the lower tank 32 comprising a separate pressurized fluid intake, which apparatus includes means for regulating the temperature of the fluid and means for measuring the speed of the fluid.

Abstract: Disclosed is an improvement of final cooling of the steel strip by immersing in cooling water, which strip has been cooled through a cooling zone in a continuous heat treating line. The improvement is achieved by injecting cooling water to the surface of the immersed strip to rapidly cool the strip to a predetermined temperature until the strip reaches the first sink-roll and resulted in that any dirt adhesion on the surface of the strip caused by contacting with the first sink-roll is prevented without increment of cooling cost.

Abstract: A method of monitoring a heating cycle of an induction heating system wherein an inductor encircles a metal workpiece and an alternating current is applied through the inductor from a power supply during the heating cycle. This method comprising the steps of generating an analog signal representative of the voltage across said inductor, as the voltage varies during said heating cycle by changes in the electromagnetic characteristics of the workpiece as the workpiece is being heated; digitizing the voltage representative analog signal; creating a trace of the digitized voltage representative analog signal, with the trace being indicative of the electromagnetic characteristic of the workpiece as sensed by the inductor voltage during the heating cycle; and, comparing the created trace with a preselected pattern.

Abstract: The process controls the cooling of a metal sheet so as to impart thereto a predetermined crystalline structure. The sheet to be cooled is passed through a case containing a mass of regularly renewed cooling fluid. The flow of the cooling fluid is controlled as a function of the inlet temperature of this fluid, in accordance with the thickness of the sheet to be cooled and the desired cooling rate.

Abstract: A steel strip which has been cooled through a cooling zone in a continuous heat treating line is finally cooled by immersing in cooling water in a cooling tank under the controlling in accordance with the following formula:- ##EQU1## With such controlling of cooling, any dirt adhesion on the surface of the strip caused by contacting with a sink-roll is prevented.

Abstract: An apparatus for measuring and regulating the variable pressure furnace gas chemistry is described. The apparatus uses a mass spectrometer for measurements, in the preferred form of the invention, in which gas species percent composition is obtained quantitatively independent of total furnace pressure variation. Using such a real time measurement capability, active control of batch process furnace operations is possible by intrinsic measurement of the part outgassing rather than by assumption of batch part status as a function of extrinsic parameters such as temperature and total pressure. Thus, by a combination of batch process temperature ramp control and variable admittance of suitable gas into the furnace, uniform batch processing is possible by closed loop control, due to renormalization of furnace residual gas chemistry from day to day drift and from batch part chemistry variation.

Abstract: A converter pressure control device for use in a converter waste gas disposing device wherein a calculator determines the difference between the pressure in a converter and atmospheric pressure and sets an operating parameter according to the detected difference. A pressure controller generates a control signal in accordance with the operating parameter and the difference in converter pressure and a predetermined value. The control signal is used to operate a damper to control the flow of waste gas through the converter.

Abstract: Fluidized-bed type carburizing furnace means of the class provided with a path for circulation of the furnace gas of a fluidized-bed type carburizing furnace is improved by incorporation therein of ejector means for spouting compressed gas into the circulation path. The circulation path comprises an outlet pipe emanating from the furnace gas outlet of the fluidized-bed type carburizing furnace, a cyclone connected through the medium of the outlet pipe to the fluidized-bed type carburizing furnace, and a discharge pipe emanating from the cyclone and joined to the furnace gas inlet of the fluidized-bed type carburizing furnace. The ejector means comprises a constriction formed in the discharge pipe and a feed pipe for compressed gas having the leading end thereof inserted into the constriction.

Abstract: A method of producing a hot, carburized metallized iron product in a generally vertical shaft furnace having an upper reducing zone in which iron oxide reacts with a gaseous reductant, and a lower carbon control and product discharge zone, including: establishing a gravitationally descending iron oxide burden in the furnace; reacting hot gaseous gaseous reductant with the descending burden to form a metallized iron product and a reacted top gas; and injecting a hydrocarbon gas mixture consisting of hot reformed reducing gas and cool natural gas to the product discharge section of the shaft furnace; whereby the carbon content of the metallized iron pellet product is controlled by mixing the reformed gas and natural gas in the proper ratio to balance the endothermic and exothermic reactions within the discharge zone of the furnace.

Abstract: A method and apparatus for maintaining a constant ejection pressure in a melt spinning process for converting a molten metal into a metal foil of a uniform thickness. The backpressure exerted against inert gas being injected into the bottom of a crucible containing molten metal is monitored. Any negative rate change in the backpressure is noted and the gas overpressure in the crucible is then increased to return the back-pressure to its original value. In another embodiment the gas flow rate of the inert gas is monitored. Any positive rate change in the flow rate is noted and the gas overpressure is then increased to return the flow rate of the gas back to normal. This maintains a constant ejection pressure of molten metal passing through the orifice of the crucible producing foil with a uniform thickness.

Abstract: A process and apparatus for measuring and regulating the variable pressure furnace gas chemistry is described. The method makes use of mass spectrometer measurements, in the preferred form of the invention, in which gas species percent composition is obtained quantitatively independent of total furnace pressure variation. Using such a real time measurement capability, active control of batch process furnace operations is possible by intrinsic measurement of the part outgassing rather than by assumption of batch part status as a function of extrinsic parameters such as temperature and total pressure. Thus, by a combination of batch process temperature ramp control and variable admittance of suitable gas into the furnace, uniform batch processing is possible by closed loop control, due to renormalization of furnace residual gas chemistry from day to day drift and from batch part chemistry variation.

Abstract: A method of producing a hot, carburized metallized iron product in a generally vertical shaft furnace having an upper reducing zone in which iron oxide reacts with a gaseous reductant, and a lower carbon control and product discharge zone, including: establishing a gravitationally descending iron oxide burden in the furnace; reacting hot gaseous reductant with the descending burden to form a metallized iron product and a reacted top gas; and injecting a hydrocarbon gas mixture consisting of hot reformed endothermic gas and cool natural gas to the product discharge section of the shaft furnace; whereby the carbon content of the metallized iron pellet product is controlled by mixing the endothermic gas and natural gas in the proper ratio to balance the endothermic and exothermic reactions within the discharge zone of the furnace.

Abstract: This process and this installation permit taking samples of blast-furnace gas from a series of orifices (T1, T2 . . . ) located at different levels along a generatrix of the body of the blast-furnace. There are performed, in sequence, operations for preparing sampling lines, operations for the analysis of the gases in a device (G), and pressure measuring operations in a pressure sensor (P). These various operations are managed by a programmable automaton (A) and the data obtained are used in a computer (C) in accordance with an embodiment of the installation.

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: In controlling the cooling of a hot-rolled steel sheet after hot rolling, a target value of a transformation rate required for obtaining mechanical properties ultimately expected from the hot-rolled steel plate is previously determined, a rate of gamma to alpha transformed fraction of the hot-rolled steel sheet in a section in which the cooling is controlled is detected by transformed fraction detectors, and an elapsed time from the start of cooling is measured to determine the transformation rate of the steel sheet in a cooling stage, the conditions of cooling being controlled so that the transformation rate can coincide with the target value.

Abstract: A vacuum furnace is cooled in a two-step process. In the first step, a noble gas is injected into the furnace to break the vacuum, and to provide initial cooling. In the second step, a non-noble, but relatively inert, gas is injected into the furnace to complete the cooling. The flow of the noble gas is cut off when the temperature in the furnace falls below the point at which the contents of the furnace will no longer react with the second gas. The invention also discloses apparatus for cooling the furnace. Temperature controllers monitor the temperature, and rate of temperature change, in the furnace, and direct controlled amounts of noble or non-noble gas into the furnace. At no time is a liquefied gas allowed to enter the furnace. The process allows the furnace to be cooled rapidly but safely, minimizing the danger of thermal shock to the internal furnace components.

Abstract: A method and apparatus for supervising a descending speed, thickness of a layer, particle size, and so on of charges in a blast furnace. Coke and ore composing the charges are detected by radiating an electromagnetic wave into the blast furnace. An electromagnetic wave can easily pass through coke, but is reflected or scattered by ore.

Abstract: A method and oven equipment for cooling a charge after thermal treatment. The charge, which is located within a closed chamber, is cooled by blowing in cooling gas. The cooling occurs as a function of the actual conditions of the charge at a predetermined speed, and a uniform distribution of temperature within the charge is assured. For this purpose, the temperature distribution in the charge is measured by temperature sensors, and the intensity and/or direction of the flow of the cooling gas can be changed if deviations from the predetermined theoretical values occur. The wall of the closed treatment chamber of the oven equipment contains a plurality of gas passages which can either be closed off, or are permeable for gases yet impermeable for heat rays. Cooling gases are conducted through the chamber via control valves. The cooling gas is circulated with the aid of a blower unit along with a gas cooler.

Abstract: A furnace control for a reheating furnace or the like is disclosed. Desired material temperature parameters are established for at least one location within the furnace and predetermined heating rates are calculated to provide the desired temperatures. The furnace burners are set in accordance with the predetermined rates. Actual temperature readings of the material are taken in the furnace and compared to the desired temperatures. Revised heating rates are established on the basis of that comparison and the predetermined rates are replaced with the revised rates. The furnace burners are continuously adjusted and updated in accordance with the revised rates thereby increasing furnace efficiency and control.

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: In the gas carburization of steel, a steel part is exposed in a carbon-enriched atmosphere of a furnace to a diffusion process to form a boundary layer with an increased carbon content, determined as a function of the distance from the surface. The values of importance for the diffusion process are determined intermittently and used as control parameters to affect the diffusion process. The flow of carbon diffusing directly through the surface of the steel part serves as the measured value. The supply of the carburizing gas is controlled as a function of this value.

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: An apparatus for quenching a butt-welded portion of a rail, includes an inverse U-shaped cooling box for covering from above and throughout a butt-welded portion of a rail, and for quenching the butt-welded portion by cooling air. The cooling box is divided into a head cooling chamber, a web left cooling chamber, and a web right cooling chamber each having a plurality of cooling air nozzles directed toward the butt-welded portion. A cooling air supply mechanism supplies cooling air to the cooling box, the cooling air supply mechanism including a cooling air source, a solenoid valve operatively arranged in a cooling air supply pipe, a head cooling air regulating valve, a web cooling air regulating valve, and a valve opening controlling mechanism which opens each of the head cooling air regulating valve and the web cooling air regulating valve according to a predetermined program.

Abstract: A method of controlling the depth of immersion of an oxygen lance in a molten bath within an electric arc furnace where noise emitted from the furnace during lancing in an acoustic spectrum ranging between 1 kHz and 15 kHz defined by a plurality of selected frequency bands is monitored. The position of the lance with respect to the bath surface is controlled by reference to the amplitudes of the output signals emitted from each of the selected frequency bands. There is a distinct change in the relationship of particular bands to provide a "lance out" signal which is directed to a control for a lance drive mechanism. Apparatus for practicing the method includes a microphone, a filter unit, a microprocessor and a lance drive responsive to signals from the microprocessor.

Abstract: An apparatus and process for rapidly injecting or blowing solid combustible material into a metal pool is presented. In a preferred embodiment, the apparatus essentially comprises at least one nonoxidizing compressed gas source, a circuit which supplies granulated carbonaceous material suspended in a carrier gas, at least one circuit which supplies flushing gas, various means for metering different flow rates of the gas and solid particulate streams and means for separately or jointly connecting the above described circuits to appropriate conduits which terminate in a blowing lance.

Abstract: The present control apparatus and method for controlling a plurality of intercoupled industrial process operations each having an operation control member. The control member position correction is implemented in accordance with a predetermined characteristic so as to minimize undesired interference with the other industrial process operations.

Abstract: The present control system and method for controlling the combustion chamber pressure in a non-linear combustion process is operative in relation to one or more combustion chambers each having a flue gas damper. In the case of a plurality of such chambers, the outlet duct associated with each chamber is connected to a common exhaust stack. This operation is in relation to a desired damper position control characteristic provided by a combination of process signals in a microprocessor computer apparatus. Information in the form of the combustion and pressure levels as supplied in an anticipative feed-forward control manner by a particular combustion chamber is utilized in conjunction with a variable gain characteristic determined by the actual position of the damper operative with that combustion chamber to determine the correct damper position for that chamber.

Abstract: A control system and method are provided for an industrial process operation, wherein a controller is coupled with a process control member and has a gain that is adjustable in accordance with a predetermined relationship of the controller reference iteration interval and the controller actual execution interval.

Abstract: A device for filtering dust from air drawn by apparatus from a factory shop or building, for example a steelmaking shop, including a plurality of dust extractors which have a total capacity at least equal to the air throughput of the drawn air. The extractors have regulators by which they can be regulated individually or in groups. Preferably each extractor is associated with an individual dust extractor and also each extractor preferably has its own individual cleaning system. The extractors are preferably of the dry filter bag type.

Abstract: A method and apparatus for controlling the pouring of molten metals in a pressure-type furnace is provided. The furnace includes a reservoir for storing the molten metal, a first passage for supplying the metal to the reservoir, and a second passage for supplying the metal stored in the reservoir to a pouring chamber where they are poured into a mold. A gas having a predetermined pressure is supplied to a pressure chamber disposed above the reservoir. An output signal from a load cell is generated representative of the amount of the metal contained in the furnace. The output signals are processed in a sampling circuit to obtain a rate of variation signal representative of variations in the amount of the metal stored in the furnace. The rate of variation signal is compared in a comparator circuit with a reference value to generate a replenishment signal indicating that the molten metal is being replenished.