2788 results about "Furnace temperature" patented technology

A method of fabricating a long carbon nanotube yarn includes the following steps: (1) providing a flat and smooth substrate; (2) depositing a catalyst on the substrate; (3) positioning the substrate with the catalyst in a furnace; (4) heating the furnace to a predetermined temperature; (5) supplying a mixture of carbon containing gas and protecting gas into the furnace; (6) controlling a difference between the local temperature of the catalyst and the furnace temperature to be at least 50° C.; (7) controlling the partial pressure of the carbon containing gas to be less than 0.2; (8) growing a number of carbon nanotubes on the substrate such that a carbon nanotube array is formed on the substrate; and (9) drawing out a bundle of carbon nanotubes from the carbon nanotube array such that a carbon nanotube yarn is formed.

Burner firing method and device are presented where an oxidizing oxygen-fuel burner is fired at an angle to the reducing air-fuel burner flame to reduce overall NOx emissions from high temperature furnaces. The oxidizing oxy-fuel burner stoichiometric equivalence ratio (oxygen/fuel) is maintained in the range of about 1.5 to about 12.5. The reducing air-fuel burner is fired at an equivalence ratio of 0.6 to 1.00 to reduce the availability of oxygen in the flame and reducing NOx emissions. The oxidizing flame from the oxy-fuel burner is oriented such that the oxidizing flame gas stream intersects the reducing air-fuel flame gas stream at or near the tail section of the air-fuel flame. The inventive methods improve furnace temperature control and thermal efficiency by eliminating some nitrogen and provide an effective burnout of CO and other hydrocarbons using the higher mixing ability of the oxidizing flame combustion products. The simultaneous air-fuel and oxy-fuel burner firing can reduce NOx emissions anywhere from 30% to 70% depending on the air-fuel burner stoichiometric ratio.

The invention relates to a fault monitor and diagnosis method of a continuous annealing unit, in particular to a PCA (Principle Component Analysis) model based furnace temperature and tension monitoring of a continuous annealing unit, mainly comprising the following steps of firstly, according to process variable data obtained in the field, and establishing a temperature and tension monitor modelby utilizing a principle component analysis PCA method; secondly, establishing an off-line model and calculating the T2 statistics quantity and the SPE statistics quantity as well as contributed control limits thereof by utilizing the data, obtained in step one, when process variable is in a normal work condition; thirdly, applying an on-line model, calculating the T2 statistics quantity and the SPE statistics quantity of current data, monitoring whether a current state is normal or not according to information supplied by the off-line model, and giving alarm signals if abnormal; fourthly, determining a leading variable which causes a fault by utilizing contribution of the T2 statistics quantity and contribution of the SPE statistics quantity. The invention monitors the furnace temperature and tension in real time in the production process and traces back a fault reason for leading to system abnormality when the abnormality occurs.

The invention relates to a cement decomposing furnace temperature control method based on constraint smith GPC, which includes variable selection, model recognition, optimizing computation, constraint processing and feedforward compensation; the variable selection includes that: coal powder flow is selected as a control variable, raw flow is selected as the feedforward variable and the decomposing furnace temperature is selected as the controlled variable; the model recognition includes that: the model recognizer based on least square method and retardation time estimation time is adopted to obtain a pulse transfer function model; the optimizing computation includes that: the future output state is predicated and the reference track w of the output value is also set; a secondary performance index controller is adopted for the rolling optimization, the control increment Delta u of the current time is computed to obtain control action value u through addition; the constraint processing includes that: the control variable and controlled variable are respectively performed with constraint amplitude limiting processing; the feedforward compensation includes that: the dynamic compensation principle is utilized to compute the current time t added to the feedforward control action value ud. The invention has simple recognition process, less adjustable parameters, good tracking performance, strong robustness, effectively refrains the disturbance influence caused by raw material flow and prevents saltus step of the system variable.

The invention relates to a method for comprehensive utilization of vanadium-titanium magnetite, which belongs to the field of new technology of direct reduction ironmaking in the metallurgical industry. In order to solve the problems of low utilization of iron, vanadium and titanium in vanadium-titanium magnetite, at the same time, due to the sintering process of traditional technology, the comprehensive energy consumption of the overall smelting process is relatively high, and the environmental pollution is serious. The invention provides a method of agglomerating vanadium-titanium magnetite and producing high-titanium slag and pearl iron by high-temperature reduction and melting in a rotary hearth furnace. The technical solution includes pelletizing of vanadium-titanium magnetite, high-temperature reduction in rotary hearth furnace, magnetic separation, and high-temperature reduction in rotary hearth furnace to directly produce high-titanium slag and pearl iron. Applying this method to process vanadium-titanium magnetite can not only effectively solve the problem of recovery of titanium and vanadium resources, but also obtain qualified iron pearls for steelmaking in electric furnaces, making full use of the iron, vanadium, and Valuable elements such as titanium.

The invention discloses a bunker coal environment-friendly synergist, which comprises the following components by weight percent: 1 to 10 percent of ammonium bicarbonate, 1 to 8 percent of sodium bicarbonate, 1 to 10 percent of sodium carbonate, 1 to 5 percent of sodium nitrate, 1 to 10 percent of potassium nitrate, 1 to 15 percent of calcium carbonate, 1 to 10 percent of sodium hydroxide, 2 to 10 percent of calcium hydroxide, 1 to 10 percent of potassium permanganate, 3 to 15 percent of potassium chloride, 10 to 35 percent of sodium chloride, 1 to 10 percent of ammonium chloride, 1 to 15 percent of calcium chloride, 1 to 10 percent of borax, 1 to 10 percent of macaroni, 1 to 5 percent of potassium carbonate, 1 to 5 percent of calcium nitrate, 1 to 5 percent of iron oxide, and the balance being micro turpentine, sulfur and paraffin wax. The bunker coal environment-friendly synergist makes flame of combustion be more rampant and denser, the furnace temperature rise to a higher level, the hearth be brighter and cleaner and tail gas be cleaner.

The invention discloses lead-free glass dust with low melting point used for glass frit slurry, as well as the preparation method and the application thereof. The lead-free glass dust is characterized in that the compositions have the following weight percentages: 50%-70% of bismuth oxide, 0.1%-30% of boric oxide, 0.1%-30% of zinc oxide, 0.1%-10% of aluminium oxide, 0.1%-10% of silicon oxide, 0.1%-10% of magnesia magnesium oxide, 0.1%-10% of titania titanium dioxide, 0.1%-5% of sodium monoxide, 0.1%-5% of potassium oxide, 0.1%-5% of calcium oxide, 0.1%-2% of cerium oxide, and 0.1%-2% of cerium oxide. The preparation method comprises the following steps: all raw materials are fully mixed; the mixed mixture is put into a crucible, and is then put into an electric furnace at the furnace temperature of 1200-1450 DEG C; the melted glass slurry is poured into a tablet machine for being pressed into sheets or poured into cold water; the flaky or granule glass and dye are put into a ball mill together for ball milling; the glass dust after the ball milling process is screened and bagged; and the glass dust is applicable to the glass frit slurry field of the dielectric layers of plasma displays, fluorescent displays and the like. The invention has the advantages that the glass dust has good insulation and high dielectric constant, and is applicable to screen printing.

The invention relates to a comprehensive control method for the outlet temperatures of a heating furnace, belonging to the field of furnace temperature control technology. The invention is characterized in that branch balance control makes the outlets temperatures of a multi-branch heating furnace uniform, and automatic load lifting and dropping can be realized. By using state feedback prediction control of measured states and feedforward control, the method effectively improves the anti-interference ability. A state space model of the heating furnace is obtained by mechanism modeling, in no need of testing devices. An on-line model is self-adaptive, which effectively overcomes process characteristic change and improves the rate of putting into operation. Low-value fuel can realize idea valve location interval control, thus saving high-value fuel. The comprehensive control of the outlet temperatures ensures the uniform and stable outlet temperatures of the heating furnace, which is easy to operate and economical.

The invention discloses a thermal treatment method for an internal spline gear with small modulus. The method has a principle similar to a press quenching and is characterized in that: a core rod with the size consistent to the size of a spline internal hole is adopted, as the size of the spline internal hole is basically consistent to the size of the core rod, the core rod is inserted into the spline internal hole when a spline is heated to the quenching temperature and is taken out of a furnace for quenching; due to the principle of expansion with heat and contraction with cold, the spline and the core rod are tightly pressed together after oil feeding; due to the limitation of the size and the shape of the core rod, the deformation is limited in a defined range. According to the thermal treatment method, a controllable atmosphere heat treatment furnace is adopted for carburization; and through controlling furnace temperature, insulation time and carbon potential and selecting a proper core rod for quenching thermal treatment, the deformation requirement after carburization and quenching of the spline internal hole can be met. Meanwhile, the grinding step is omitted, the use requirements of a carburized layer and the hardness of the core part of a part can be ensured.

The invention relates to a wood microwave vacuum drying and charring device and a drying and charring method thereof. The device comprises one charring tank (box) with a tank door (3), a tank door opener (2) and a charring chamber (1), a vacuum system, and one or more microwave sources (6) generating the microwave, a heat-conducting oil furnace system and a material preparation and feed system. The drying and charring method comprises the following steps: A. rising the temperature inside the tank to 30-50 DEG C, and then to 80-130 DEG C at the rate of 2-8 DEG C/h; B. preserving the temperature for 2-100 hours; C. vacuumizing the tank for 4-100 hours; D. starting a hot recycle pump to control the oil furnace temperature, the oil flow rate and the pressure inside the tank for 4-100 hours: E. turning off the microwave source and a heat source, opening an intake and exhaust valve (39) to discharge the pressure inside the tank to 0 and lower the temperature to 70-130 DEG C, and then closing the intake and exhaust valve (39); and F. starting a vacuum pump (22) to lower the temperature inside of the tank by air circulation and removing the wood from the tank when the temperature decreases to 30-70 DEG C. The device and the method help char the wood evenly, shorten the production cycle by 60% compared with the conventional method, and lower the energy consumption by 70%, thus greatly reducing the production cost.

The invention relates to an optimization control method of blast furnace temperature. The temperature control of the existing blast furnace ironmaking enterprises is determined by experience, thus the temperature control is inaccurate. In the optimization control method, time lag and uncertainty of actual parameters are considered; the blast furnace temperature is predicted by establishing a predication model of a steplike dynamic matrix predictive control algorithm, and then links such as rolling optimization, feedback compensation and the like are performed, thus ensuring to obtain an optimum and stable use amount of the three factors, that is, coal injection amount, blast volume and cooling water flow rate. The method comprises the specific steps as follows: establishing an admissible control set and the predication model, and performing model conversion, the feedback compensation and the rolling optimization to obtain an optimum control rate. The time lag and the uncertainty of the actual parameters as well as correction model error are considered in the method, thus ensuring to generate the optimum coal injection amount, the blast volume and the cooling water flow rate.

The invention discloses a fractional-order PID control design method based on the phase margin and cutoff frequency, and relates to the technical field of process control application. Aimed at characteristics of large inertia, nonlinearity and model uncertainty in furnace temperature control of an intermediate-frequency induction electric furnace, the method is provided. A controller is derived from internal model control (IMC) and a fractional-order filter, only two adjustable parameters are included, convenience is provided for setting of controller parameters, and parameter setting of the fractional-order (PID) gamma controller is realized based on the phase margin and cutoff frequency of a control system. The method enables that a temperature control system has high set value tracking and interference inhibiting features, and enables higher robustness during parameter perturbation of the system.

The invention relates to a method for controlling combustion atmosphere in a large-scale walking beam type plate blank heating furnace, which belongs to the technical field of fuel combustion of industrial furnaces. A plate blank is heated through a preheating section, each heating section and a soaking section to finish the process of heating and temperature equilibrium; and in the process, a first-level computer control system and a second-level computer control system automatically generate a heating process and automatically set and control the furnace temperature in each section according to original data of the plate blank called from a database; and on the basis of an output control value of a residual oxygen analyzer, the computer control systems calculate the air consumption coefficient of each combustion area, perform dynamic track on the combustion atmosphere in the whole furnace along with the changes of thermal loads, correct the combustion atmosphere according to the actual air-fuel ratio of six combustion areas, adjust the proportion of combustion air and gas, and determine the reasonable air and gas flow to achieve the furnace temperature required by the heating process. The method has the advantages that the condition of furnace gas component changes in the furnace is quantificationally provided for a heating furnace operator in time, so that the combustion in the heating furnace reaches good state; and simultaneously, the energy-saving and environmental protection effects are remarkable.

The invention provides a method and a system for self-adjusting fuzzy PID (Proportion Integration Differentiation) parameters in a furnace temperature control system. The method comprises the following steps: selecting and quantifying variables in a PID controller and finding out a fuzzy relation of three PID control parameters including a proportionality coefficient KP, an integral coefficient KI and a differential coefficient KD , and system deviation e and a deviation varying rate ec; establishing a fuzzy relation table; and carrying out online modification on the three parameters by a fuzzy control method. The system corresponds to the method. After PID parameter online fuzzy self-adjustment is carried out, a normal working state is automatically switched, and a PID parameter adjusting process is automatically started when system performances are changed and the readjusted PID parameters so that the system has the better control quality.

The invention discloses a subminiature minimal invasion high-temperature creep fatigue testing machine and the application thereof. The subminiature minimal invasion high-temperature creep fatigue testing machine mainly includes a driving system, a loading device, a constant temperature atmosphere furnace, a temperature control system, a high temperature gas protection system, a measurement control system and a water cooling system, wherein the loading manner of the machine is top vertical loading; a testing sample is positioned between an upper fixing platform and a lower fixing platform; and when loading is performed, a servo motor controls a lower loading rod to move upwards, a jumper bar is contacted with an upper loading rod, the lower end of the jumper bar is used for testing sample stamping through a pressure head. Aiming at an existing structure and a domain structure at a high temperature, the testing machine provided by the invention can be used for obtaining various high temperature performance of the material and estimating residual service life creep, safety operation state and the like of the high temperature structure, is convenient to operate, is uniform in testing temperature and high in testing precision, can be used for testing various high temperature performances such as high-temperature creep performance, high-temperature relaxation performance, high-temperature creep fatigue performance and high-temperature breaking toughness of the material.

The invention relates to a three-step variable-temperature diffusion process for a silicon cell, which is realized by the following procedures: placing a silicon chip after etching into a boat, then rising the temperature to be 700-810 DEG C, and introducing large nitrogen, small nitrogen and oxygen to conduct low-temperature pre-deposition diffusion; subsequently rising the temperature to be 810-830 DEG C, and introducing large nitrogen to conduct knot thrusting; and then introducing large nitrogen, small nitrogen and oxygen, and rising the furnace temperature to be 830-870 DEG C to conduct secondary deposition diffusion. A multi-level PN knot structure formed after diffusion can ensure good ohmic contact with a metal gate wire on the one hand, and can have good blue response on the other hand; in addition, a PN knot formed by the method has great knot depth, and the possibility that the PN knot is burnt through, subjected to leakage of electricity and composited can be reduced.

The invention discloses a test device and a test method for simulating in-situ underground coal gasification. The test device comprises a gasifying furnace body, a top cover, a furnace wall injection pipe, a furnace wall exhaust pipe, a gasifying agent preparing unit, an injection pipeline, an exhaust pipeline, a gas flow meter, a gas pressure meter, a gas temperature measuring thermocouple, a gas purifying unit, a gas dispersing unit, an inside-furnace temperature monitoring unit, a gas chromatograph, an igniter, a displacement meter, a filling unit and a computer, wherein the outer shape of the gasifying furnace is cylindrical; the wall of the gasifying furnace comprises a steel plate, a common brick layer, an insulation material, a water jacket layer and a refractory brick layer from outside to inside sequentially, The test device is reasonable in structure and multifunctional, and can utilize instruments to objectively and actually measure temperature fields in a coal seam and a roof rock stratum, gasifying agent ratio and gas production index parameters, overlaying rock movement and ground surface subsidence parameters, and gasifying furnace cavity-growth characteristic parameters, and facilitate research on furnace structure parameters and a gasifying process, so as to determine in-situ underground coal gasification process parameters and an in-situ underground coal gasification production scheme, which are suitable for on-site conditions.

The invention relates to a method for the fuzzy control of the temperature distribution of steel billet in a heating furnace. The method utilizes a compensation control component fuzzy reasoning module and a compensation control weighted integration component module to form a diffusion reasoning fuzzy controller of the temperature of the steel billet; the temperature deviation distribution between the temperature distribution of the steel billet and the perfect heating curve of the steel billet is used as input information of the fuzzy controller; for each adjusting point of the furnace temperature, one set of two-dimensional fuzzy controllers of the compensation control component fuzzy reasoning module is utilized to generate a set of furnace temperature compensation control components; and the compensation control weighted integration component module is utilized to integrate the set of the furnace temperature compensation control components so as to obtain the compensation dosage of the furnace temperature of each part. Through the dispersive fuzzy reasoning structure, the method solves the difficult problems that the prior fuzzy dynamic compensation control technology is difficult to effectively process high dimensional input information, can fully consider the temperature deviation distribution and the changing trend of the steel billet after the adjusting point of the furnace temperature in the process of adjusting the furnace temperature and better ensure the steel billet to be heated completes heating according to the perfect heating curve.

The invention discloses a high-temperature Hopkinson pressure bar experimental system with an atmosphere protection device. The whole system comprises an atmosphere protection device, a heating system and a loading system, wherein the atmosphere protection device comprises a protection box, an exhaust emission pipeline and an exhaust filtering device, wherein the protection box is provided with a protective gas inlet, an exhaust emission hole and a cooling gas inlet, and a seal suite is arranged between the protection box and a wave guide bar; the heating system comprises a heating furnace, an armoured thermocouple and a thermocouple wire, wherein the armoured thermocouple is used for monitoring furnace temperature, and the thermocouple wire is welded on a test piece by spots and is used for measuring the temperature of the test piece. The whole heating furnace, the armoured thermocouple for monitoring furnace temperature and bar ends of two wave guide bars are separately arranged in the protection box. The invention can adopt two experimental methods for firstly heating the test piece, and then assembling the test piece and the wave guide bars or heating the test piece and the wave guide bars simultaneously. The experimental system not only can conveniently carry out a high-temperature dynamic experiment of special materials in a protection atmosphere, but also can be used for a high-temperature dynamic experiment in common air.

The invention discloses a method for rolling a thin high-strength steel plate of a single-frame steckel mill. The method comprises the following steps: producing the finished product of a high-strength steel plate with a thickness less than 10 millimeters by using a blank with the thickness of 150 millimeters and the length more than 10 meters; and then acquiring the thin high-strength steel plate with qualified property and plate shape by controlling a tapping temperature, a coiler furnace temperature, a reduction in last pass, a roller force, a final rolling speed and a high pressure water de-scaling system. When the rolling method is used for producing the thin steel plate, the thin high-strength steel plate is rolled by utilizing the heat preservation function of front and back mill coiler furnaces and controlling the tapping temperature of the blank, the reduction in the last rolling pass, the roller force and the final rolling speed, and the acquired plate shape and property of the steel plate are both qualified, thereby increasing the rolling mill capacity and achieving high plate yield and high property yield.

The invention discloses a diffusion connection method for a TiAl alloy and a Ti2AlNb alloy. By controlling diffusion connection process parameters and carrying out furnace pressure and temperature keeping treatment, reliable connection between dissimilar intermetallic compounds is achieved, and a certain basis and support is provided for the study and manufacturing of complex structural components. According to the diffusion connection method, by controlling three variable parameters of the diffusion connection temperature, the deformation amount and the time and carrying out furnace temperature keeping treatment, an interlayer is not added, reliable connection of the alloys is achieved through mutual reactions and diffusion of main elements of Ti, Al and Nb and other microelements, and application and popularization of the TiAl series intermetallic compounds are facilitated; and a TiAl alloy and Ti2AlNb alloy diffusion connection piece is used for aerospace light high-temperature structural components, the properties of the two kinds of materials can be effectively achieved, and great application prospects are achieved.

The invention relates to the technical field of heating furnaces of heat treatment equipment applied in the steel rolling industry, in particular to a high-efficiency intelligentized heating furnace control method. The method adopts a PLC (programmable logic controller) system for field control and an upper computer operating system communicating and connected with the PLC system to form an intelligent control system, and moreover, the intelligent control system is utilized to efficiently, scientifically and intelligently control a heat furnace. The method is characterized in that the intelligent control system controls and sets the heating furnace in the following six aspects: (1) furnace temperature control; (2) internal pressure control; (3) air-fuel ratio control; (4) safety protection system control; (5) adoption of an human-machine interface (HMI) on the intelligent control system; (6) history data recording. The method can reasonably control heating temperature, furnace temperature and furnace pressure at each stage in real time, increases the heating utilization rate, has an outstanding effect in saving energy and reducing consumption, increases the production efficiency, reduces the production cost, and prolongs the furnace service life.

A method for determining a furnace-temperature set value of a billet heating furnace is disclosed and used to determine the furnace-temperature set value of the heating furnace. The method comprises the following steps: S1, predicting a difference between a current control segment outlet temperature and a theoretical target temperature according to a billet temperature calculating model, taking the difference as an feedforward input parameter of a PID circuit to obtain a feedforward furnace-temperature correction value; S2, obtaining a difference between a billet discharge detection temperature and a billet discharge target temperature by a temperature measuring apparatus at the back of the furnace, taking the difference combined with feedback coefficients of each furnace segments as an feedback input parameter of the PID circuit, to obtain a feedback furnace-temperature correction value; and S3, according to current furnace temperature of each furnace segments, feedforward/feedback furnace temperature correction values and heating/cooling speeds, determining the furnace-temperature set value T(i, t+ delta t) of each furnace segments. According to the method for determining the furnace-temperature set value of the billet heating furnace, anticipatory control on the billet in the furnace and feedback control on the discharge billet are integrated, and the PID circuit is used to determine the furnace-temperature set value of each control segment, so that the inside temperature of the furnace is accurately controlled, and thus the rolling technological requirements are satisfied and automatic steel sintering is realized.