1195 results about "Electric furnaces" patented technology

The invention discloses a strength determination method for reacted blast furnace coke, which comprises the following steps of: (1) placing a coke sample in a reactor; (2) putting the reactor in an electric heating furnace; (3) inserting a temperature thermocouple into the coke in the reactor;(4) putting an electronic balance on a lifting table and connecting the electronic balance and the reactor through a chain; (5) regulating the electric furnace to heat through a temperature controller and introducing nitrogen when the temperature in the center of a material layer reaches 400 DEG C; (6) introducing carbon dioxide gas when the temperature in the center of the material layer reaches 780 DEG C; (7) cutting the nitrogen and introducing prepared mixed gas when the temperature in the centerof the material layer reaches a certain value, maintaining the temperature of the heating furnace, and when the loss ratio of the coke samples reaches the required value continuously introducing the carbon dioxide gas or the mixed gas, introducing the nitrogen and cooling after the carbon dioxide gas or the mixed gas reaches the specified dissolve loss quantity; and (8) stopping introducing the nitrogen and cooling naturally when below 100 DEG C. The invention more truly reflects the actual conditions of the coke in a blast furnace, and the prediction of the thermal properties of the coke is more accurate.

The invention relates to a preparation method of foamed aluminum, in particular to a method for preparing the foamed aluminum by primarily foaming a melt, which can prepare a foamed aluminum product by primarily foaming aluminum. The method comprises the following steps of: starting a thermoelectric furnace for heating to 800 DEG C until the aluminum is fully molten; lowering the temperature to 680 DEG C, adding metal calcium into aluminum liquid and stirring so as to increase the surface viscosity of the melt; pretreating titanium hydride, adding pretreated titanium hydride into the melt and stirring to uniformly distribute the titanium hydride in the melt for full decomposing; and heating a mold, putting the melt into the thermally-treated mold, preserving heat and foaming at the temperature of 650 DEG C, taking a prefabricated member out, performing air cooling to shape the high-temperature foam melt in the mold and taking the prefabricated member out for water cooling so as to obtain the foamed aluminum product. When applied to a filling piece of a regular cavity, the method simplifies a process, greatly lowers production cost, is suitable for diversified development of industrial production and brings convenience to the research of specific technology.

The invention provides a high-boron high-speed steel roller material and a smelting process thereof. The smelting process of the high-boron high-speed steel roller material comprises the following steps: firstly, adopting Q235 waste steel, ferrotungsten, ferromolybdenum, ferrovanadium, high carbon ferro-chrome, metal copper, metal aluminum, calcium-silicon alloy, rare earth ferrosilicon magnesium alloy, ferrocolumbium, ferroboron, ferrosilicon, vanadium-nitrogen alloy, zirconium ferrosilicon and ferrotitanium as materials for smelting low-alloy high-speed molten steel in an electric furnace; then, adding the ferrovanadium and part of ferroboron to carry out alloying in a discharging process; finally, adding part of ferroboron and composite modificator in a casting ladle, adding the vanadium-nitrogen alloy, the zirconium ferrosilicon, the ferrosilicon and part of ferroboron in the casting process. The obtained casting piece has a little alloy elements, excellent abrasive resistance and good thermal fatigue resistance. When the high-boron high-speed steel roller material is used as a roller, the service life is prolonged by more than six times relative to a high nickel-chrome infinite cast-iron roller, and prolonged by 20% relative to a high-vanadium high-speed steel roller. Moreover, the roller is safe to use and reliable.

The invention relates to hot-work die steel for an extrusion wheel and a manufacturing method of the die steel. The invention adopts the technical scheme that the manufacturing method comprises the following steps: hot-forging after scrap steel or molten iron and scrap steel are smelted in an electric furnace and are subjected to electroslag remelting or vacuum induction melting and then carry out spheroidizing annealing at a temperature of 700-880 DEG C; quenching at a temperature of 1,020-1,120 DEG C and tempering at a temperature of 530-650 DEG C, wherein the hot-work die steel has a hardness of up to 40-52HRC and a tensile strength of up to 1,850-1,955MPa. The hot-work die steel comprises the following chemical components in percentage by weight: 0.30-0.50wt% of C, 0.80-1.20wt% of Si, 0.2-0.5wt% of Mn, 3.00-5.00wt% of Cr, 1.00-1.50wt% of Mo, 0.70-1.20wt% of V, 0.005-0.03wt% of N and less than 0.030wt% of P, less than 0.030wt% of S and the balances of Fe and inevitable impurities. The steel has the characteristics of low cost, good thermal fatigue property, high heat stability and excellent comprehensive property and can be used for manufacturing the extrusion wheel of a continuously-extrusion-molded coating machine and other hot-work dies.

Belonging to the technical field of alloy steel preparation processes, the invention relates to an ultrahigh thermal conductivity wear-resistant hot stamping die steel and a manufacturing method thereof. Current hot stamping die steel on the market is mainly various improved H13, H11 and other high alloy hot work die steel. The steel provided by the invention comprises the following components by mass percent: 0.33-0.40% of C; less than 0.30% of Si; less than 0.30% of Mn; 1.0-2.0% of W; 4.0-5.0% of Mo; less than 0.30% of Cr; 0.10-0.20% of V; and the balance Fe and inevitable impurities. And in the impurity elements, S is smaller than or equal to 0.01%; P is smaller than or equal to 0.01%; and O is smaller than or equal to 30ppm. The steel is characterized in that: simple C, Mo and W are adopted as the main elements to coordinate the ratio of carbides; low Mn, low Cr and low Si content are maintained; after electric furnace smelting, electroslag remelting, annealing, high temperature homogenization, forging and annealing, the material has good machining properties; and after heat treatment, the material has excellent impact toughness, tempering stability and thermal fatigue performance. With ultrahigh thermal conductivity, the steel can be more suitable for hot stamping.

The invention discloses a preparation technology of a TC17 titanium alloy wire. The preparation technology is characterized by comprising the following steps of: rolling the TC17 titanium alloy into a disk with specification of (Phi)12mm; performing three times of grinding on the (Phi)12mm disk; after the grinding and when the total working rate reaches 30%, performing heat treatment and stress relief annealing in an electric furnace or a vacuum furnace; when the diameter of the wire is greater than or equal to (Phi)10mm, controlling the stretching temperature at 780+/20 DEG C; when the diameter of the wire is less than (Phi)10mm, controlling the stretching temperature at 730+/-20 DEG C; repeatedly performing annealing-stretching-grinding-annealing of the wire after the heat treatment until the diameter of the wire is greater than or equal to (Phi)5.5mm, and performing vacuum heat treatment; before obtaining the finished product and after performing the vacuum heat treatment, removing the lubricant and scale impurity layer on the material surface by use of a round-blade mould with 0-5 degrees of internal and external taper angles according to the diameter of the finished product, stretching to obtain a bright wire with diameter of less than or equal to (Phi)5.0mm, and checking the finished product; and if the finished product is qualified, delivering as the finished product. The preparation technology disclosed by the invention makes up for the shortcoming that the TC17 titanium alloy wire cannot be produced domestically.

The invention belongs to the field of metallurgy and discloses a smelting process of Cr-Mn series spring steel. The smelting process of Cr-Mn series spring steel comprises the following steps: (1) by taking a low-sulfur molten iron and a high-quality steel scrap as the electric furnace smelting iron and steel materials, controlling the electric furnace end point carbon content to greater than 0.15%; (2) adding active lime and composite refining slag in the electric furnace tapping process, and adding calcium carbide to perform pre-deoxidation in the tapping process; (3) feeding an Al line in an argon station before LF refining; (4) producing high basicity white slag in the refining earlier stage and controlling the basicity of slag in the refining middle and later stages to 1.5-2.5; (5) controlling the ultimate vacuum front argon flow to 15-25 L/min and controlling the ultimate vacuum late argon flow to 30-45 L/min; (6) adding a granular alkaline covering agent and a carbonized rice hull to perform double protection by VD emptying; and (7) stabilizing the speed of continuous casting to 0.8-0.9 m/min, and controlling the degree of superheat to 20-30 DEG C. By adopting the process, the non-metallic inclusion content in the molten steel is reduced.

The invention discloses a method for preparing a magnesium and aluminum dissimilar metal clad plate. The method comprises the following steps: the removing of oxidization films on the surfaces of a magnesium plate material and an aluminum plate material, the stacking of the magnesium plate material and the aluminum plate material together, the continuous firm welding of four sides by a pulsed tungsten argon arc welding method, the placement of a magnesium and aluminum superposition piece in a tank-type electric furnace after four-side welding, the pressing of the superposition piece, the heating of the magnesium and aluminum superposition piece at a temperature of between 460 and 520 DEG C, the implementation of diffusive connection and other steps. The method does not need to adopt vacuum heating equipment with high price, has low connection temperature, can obtain the magnesium-aluminum diffusive welding clad plate of a crack-free brittleness-free compound in a common tank-type electric heating furnace; and the shearing strength of a connecting interface is between 22 and 30 MPa (reaching 50 percent of the shearing strength of a mother aluminum material) and can meet the using requirement of the magnesium and aluminum dissimilar clad plate.

The invention provides a method for recovering valuable metals by cooperatively disposing copper-nickel-cobalt smelting slag and gypsum slag. The method comprises: firstly adding solid or liquid copper-nickel-cobalt smelting slag into a slag-cleaning electric furnace, powering on for heating and constantly keeping a certain temperature scope, taking nitrogen as a carrier and spraying a reducing agent, the gypsum slag and a flux into the slag-cleaning electric furnace, so as to product a metal sulfonium phase and cleaned furnace slag through a reduction sulfuration reaction; and keeping warm, standing, sending the metal sulfonium phase to a fire-process blowing system through a siphon port for further recovering valuable metals, discharging the cleaned furnace slag from a slag discharge port and directly performing water quenching, so as to obtain the water-quenched slag which is applicable as a raw material for producing cement. By cooperatively disposing the copper-nickel-cobalt smelting slag and the industrial byproduct gypsum slag, efficient enriching recovery of copper, nickel, cobalt, gold, silver and other valuable metals in the smelting slag is realized, also an effective comprehensive utilization approach is provided for gypsum slag, and environmental pollution is avoided.

A rare earth alloy iron pan production method includes: (1) smelting cast iron by an intermediate frequency furnace, and heating the iron molten iron till the temperature is higher than 1400 DEG C; (2) smashing rare earth ferrosilicon alloy till the size ranges from 2mm to 6mm, and preheating till the temperature reaches 60 DEG C; (3) placing the rare earth ferrosilicon alloy block with a quantity of weight ratio ranging from 0.3% to 1.8% in a ladle and then pouring the molten iron, and mixing and drossing; (4) casting after the molten iron is cleared, preheating a casting mold and injecting the molten iron to the mold, and pressing an upper pan mold down to form an iron pan; (5) taking out the iron pan after the iron pan is chilled in the mold, and clearing in a mechanical fine grinding and buffing manner; (6) feeding the iron pan into an electric furnace, heating till temperature ranges from 270 DEG C to 330 DEG C, painting edible vegetable oil on the pan body to form an oil film, and allowing oil molecules to penetrate in the pan body; and (7) taking out the iron pan and detecting. The rare earth alloy iron pan production method has good social benefit and economic benefit, and is adaptable to the field of iron pans.

The invention discloses a control method for producing low temperature spheroidal graphite cast iron, and relates to spherical graphite-containing cast iron alloy. The control method comprises the following steps of: weighing 3.4 to 3.9 mass percent of C, 1.8 to 2.5 mass percent of Si, 0.1 to 0.4 mass percent of Mn, 0.035 to 0.07 mass percent of residual Mg and the balance of Fe, smelting and desulfurizing in a cupola furnace, transferring to a medium-frequency induction furnace for continuous smelting, adding a spheroidizing agent and an inoculators for spheroidization and inoculation, and casting to obtain a spheroidal graphite cast iron casting for a wind turbine. In the method, by controlling the components of the spheroidal graphite cast iron and improving a spheroidization and inoculation process, the number, size, morphology and distribution of graphite nodules are controlled; the cupola furnace and the medium-frequency induction furnace are adopted for double smelting; and the produced spheroidal graphite cast iron casting meets the impact toughness requirement and strength requirement at low temperature of wind turbine castings, and overcomes the defect that deformation or stress concentration easily occurs when the spheroidal graphite cast iron casting is subjected to heat treatment in an annealing mode, and defect of high cost in the prior art.

The invention discloses a yellow phosphorus preparation method and yellow phosphorus preparation equipment, which produce no phosphorous slurry and reduce the dust content of tail gas. The yellow phosphorus preparation method comprises the technological processes of electric furnace smelting, furnace gas purifying and phosphorus collecting and refining. In the process of furnace gas purifying, the furnace gas discharged out from an electric furnace is guided into a furnace gas dust-collection system through a smoke discharge pipeline, the furnace gas dust-collection system at least comprises a filter for filtering the furnace gas, the filter is provided with a sintering inorganic porous material filter element meeting the following working conditions, and the operations executed on the filter comprise the operation executed during starting a machine, the operation executed during normal operation, the operation executed during back flowing and the operation executed during stopping the machine; in the operation executed during starting the machine, pre-heated inertia gas is injected into the filter so as to preheat the sintering inorganic porous material filter element in the filter to the temperature of more than 187.5 DEG C, and in the operation executed during the normal operation, the to-be-filtered furnace gas of which the temperature is kept at 420-590 DEG C is input into the filter and the dust content of the filtered clean furnace gas is lower than 10-20 mg/m<3>.

The invention relates to 4Cr5MoSiV1 hot work die steel, in particular to a preparation method for improving the performance of the 4Cr5MoSiV1 hot work die steel. The preparation method comprises the steps of producing highly-clean steel ingots with the total oxygen content being 12 ppm by adopting electric furnace smelting, vacuum carbon deoxidizing and slag surface diffusing and deoxidization refining, adding the pure rare earth La and Ce on the oxygen control condition and carrying out argon shield pouring; carrying out diffusing and homogenizing annealing on the steel ingots and upsetting and drawing forging on the steel ingots in the three-dimensional directions three times, fast cooling the steel ingots through water and air alternately after forging, carrying out the processes of fast cooling after ultrahigh-temperature austenitizing and spheroidizing annealing before quenching, carrying out tempering with the temperature not lower than 590 DEG C 2-3 times after quenching, and finally obtaining the stable tempered structure of the 4Cr5MoSiV1 hot work die steel. According to the invention, the single notched impact property KV2 of the 4Cr5MoSiV1 hot work die steel is greater than or equal to 25 J, the average notched impact property KV2 is greater than or equal to 30 J, the single non-notched impact energy is greater than or equal to 280 J, the average non-notched impact energy is greater than or equal to 320 J, the ratio of the transverse non-notched impact energy to the longitudinal non-notched impact energy is greater than or equal to 93%, and the isotropy is excellent.

The invention relates to a production process of steel, in particular to a smelting process of steel for a high-titanium alloy welding wire. The smelting process comprises the following steps of: in an electric furnace smelting step, adding molten iron and waste steel and tapping molten steel, wherein the molten iron accounts for 50-60% the total amount of the furnace charge, and the tapping temperature is not lower than 1630 DEG C; in a refining furnace refining step, adding silicon-aluminum-calcium deoxidant in a refining furnace for manufacturing white slag through diffusion deoxidization, and adding low-carbon ferromanganese and ferrosilicon according to steel grade component requirements and sampling component analysis to regulate components of the molten steel so as to reach temperature of 1630-1650 DEG C matching vacuum treatment; in a vacuum furnace degassing step, keeping the temperature for 10-15min under a low vacuum degree of 1 millibar, and carrying out secondary refining after vacuum breakage; and in a secondary refining step, adding low-aluminum ferrotitanium to regulate titanium content at the refining temperature of 1585-1600 DEG C, stirring for 1-2min, adding iron sulfide, stirring for 1-2min, taking a lollipop sample to analyze, continuously keeping static stirring, carrying out soft argon blowing for 15-40min after all components are qualified and carrying out continuous casting when the temperature is up to 1565-1585 DEG C. The smelting process disclosed by the invention can effectively control purification degree of the molten steel, ensures stability of titanium in the molten steel and improves the surface quality of a cast blank.

The invention discloses chemical compositions of ferrite ductile iron used at low temperature and a manufacturing method of the ferrite ductile iron, determines the range of the chemical compositions of the ferrite ductile iron used at low temperature being minus 40 DEG C and provides a quality standard for the production of qualified and stable ductile iron workpieces. The manufacturing method comprises the steps of adopting pure iron, a carburant and silicon iron as raw materials, synthesizing and melting the raw materials in an electric furnace, conducting spheroidization on the raw materials by utilizing a low-rare-earth spheroidizing agent, and producing the ferrite ductile iron by adopting a combined inoculation method. According to the method, the purity of molten iron is improved stably, and the difficulties of high phosphorus, sulphur, titanium, other imputies and interference elements contents in the molten iron, large fluctuation and instability are solved. According to the method, a novel technical scheme is provided for the production of ferrite ductile iron workpiece which contains small, circular and smooth ductile iron and does not contain cementite and iron phosphide eutectic basically, the ferrite ductile iron can meet the demands of high-performance ferrite ductile iron workpiece in electrical industry, high-speed rail industry and the like, the dependence on imported products can be broken; and the running safety of nuclear power and the high-speed rail can be improved substantially.

The invention relates to a preparation method of high-toughness and high-thermal-stability hot work die steel. The preparation method comprises the following steps of optimizing alloy components, andstrictly controlling the production process; and the specific process route is as follows, electric furnace smelting, ladle refining furnace refining, vacuum refining furnace refining, electrode blankcasting, protective atmosphere electroslag furnace remelting, forging, ultrafine treatment and spheroidizing annealing production processes are adopted at the same time. The invention further relatesto the high-toughness and high-thermal-stability hot work die steel prepared through the preparation method. The product has the advantages of uniform annealed microstructure, favorable spheroidizedstructure, fine and uniform grain distribution and uniform quenched and tempered structure, and the fine precipitated phases of the Mo and Cr carbides have the dispersion strengthening action in the use process, thereby enhancing the properties of the material and endowing the material with high toughness and high isotropy. The product can be widely used for manufacturing hot extrusion dies, mandrels, hammer dies of die forging hammers, dies of forging presses and dies for precision forging machines, and particularly can be used as a high-end die-casting die made of aluminum, copper and alloysthereof.

The invention relates to a process for extracting titanium from titanium-containing blast furnace slag through an aluminothermic method, and the process comprises the following steps of: crushing the titanium-containing blast furnace slag which contains the main components of TiO2, SiO2, CaO, Al2O3 and MgO, and grinding to 180 meshes; blending slag, aluminum powder and CaO according to a certain mass ratio; aluminothermic reduction: raising the temperature of an electric tube furnace to set the temperature at the atmosphere of argon shield, placing a blended mixture into an aluminum oxide crucible, placing into the electric tube furnace at high temperature, and preserving the temperature for a certain time; water cooling: taking out at high temperature, and placing into water for cooling; and mechanically separating the slag and an alloy. According to the invention, the completely preprocessed titanium-containing blast furnace slag is reduced by using the aluminum powder, and the slag and metal are separated through the water cooling after the reduction is completed; and finally, the main components of the slag are CaO, MgO and Al2O3, the metal components are Si and Ti, and the slag also contains a small amount of Al.The process disclosed by the invention is simple in process and stable in process parameter, and can realize the enriched extraction of titanium contained in blast furnace slag in a short time.

The invention discloses a method for recycling valuable metals in waste lithium ion batteries. The method comprises the following steps: mixing waste lithium ion batteries with carbon powder, feeding into a rotary kiln for low-temperature reduction roasting, and controlling the roasting temperature to be less than 900 DEG C during low-temperature reduction roasting, so as to obtain a roasting product, wherein the amount of the carbon powder is not greater than 30% of that of the waste lithium ion batteries; mixing the roasting product with a slag former, so as to obtain a mixed material, wherein the mass of the roasting product accounts for at least 10% of that of the mixed material; feeding the mixed material into an electric furnace for smelting, so as to obtain an alloy with valuable metals and slag with CaO and SiO2. The method has the remarkable advantages of simple equipment, low investment operation cost, easiness in popularization, remarkable process energy consumption reduction, high valuable metal recycling rate and the like.

The invention relates to a wet process for building a 3t intermediate frequency electric furnace. By the process, 3t of materials can be melted, and the service life is prolonged. The process comprises the following steps of: (1) manufacturing a steel crucible die which has a shape of a truncated hollow cone; (2) paving an insulation layer and a thermal insulation layer by using two layers of asbestos cloth; (3) paving a furnace bottom, namely paving two layers of asbestos cloth at the furnace bottom in a staggered mode; (4) paving a furnace wall, namely paving two layers of asbestos cloth next to the inner wall of an induction coil from top to bottom, ensuring that each layer is flat and does not have any wrinkle, adhering longitudinal joints for lapping by using water glass, staggering joints of two adjacent layers, and adhering the asbestos cloth which stretches out of the upper plane to a fireproof brick plane at an upper opening of the furnace by using the water glass; (5) preparing a furnace lining material from refined quartz sand; (6) manually knotting a furnace lining, brushing a layer of water glass before filling, and tamping a filler; and (7) baking the furnace and sintering, namely baking only by using firewood after the furnace is built by the wet process, adding 50 to 60kg of firewood into a hearth for several times, and completely combusting to bake the furnace lining.

The invention provides a low-cost superhydrophobic surface treatment method of aluminum alloy, which comprises the following steps: (1) carrying out chemical etching on the surface of the aluminum alloy by utilizing hydrochloric acid aqueous solution with the mass-volume concentration of 70g/L-95g/L in water bath at the temperature of 30-50 DEG C for 3-6min; and (2) carrying out evaporation modification on the surface of the aluminum alloy by utilizing long chain fatty acid solution by an evaporation method, wherein, the long chain fatty acid comprises at least one of lauric acid and stearic acid, and the long chain fatty acid solution is prepared by dissolving fatty acid into an ethanol solvent based on the mass percent of 3wt.%-15wt.%. The evaporation method comprises the following steps: placing the long chain fatty acid solution and the aluminum alloy subject to chemical etching treatment in a sealed container; putting the sealed container in a chamber electric furnace, heating until the temperature of the mixture is up to 100-200 DEG C, and performing heat preservation for 1-3h; and taking out the aluminum alloy and placing the aluminum alloy in the chamber electric furnace again, curing at the temperature of 50-90 DEG C for 0.5-1.5h, and finally taking out the aluminum alloy, and carrying out air cooling on the aluminum alloy to obtain the aluminum alloy surface which has the advantages of good superhydrophobic characteristic and less possibility of being adhered to water drops.

The invention relates to a method for forging a wind power generation spindle. The method comprises the step 01 of selecting and adopting a steel ingot having sequentially undergone electric furnace smelting, external refining and vacuum degassing smelting to serve as a raw material, performing hot cutting on a steel ingot tail; the step 02 of feeding the steel ingot to a furnace and heating the steel ingot to an initial forging temperature of 1250+/-10 DEG C, performing heat insulation for 7-10 h and then discharging the steel ingot out of the furnace and forging the steel ingot; the step 103 of performing primary heating, performing upsetting twice and performing drawing-out twice and then forming preformed blank, namely T-shaped blank; the step 04 of performing secondary heating and finish forging forming; the sep 05 of performing air cooling, and performing post-forge air cooling, normalizing twice and tempering heat treatment on a forged piece; the step 106 of taking the forged piece out of an annealing furnace, enabling the forged piece to undergo the whole body 100% black skin ultrasonic flaw detection, performing rough machining after the ultrasonic flaw detection passes, and performing 100% nondestructive detection on the forged piece after the forged piece undergoes the rough machining and comes to light; and the step 07 of performing hardening and tempering. The method for forging the wind power generation spindle reduces plenty of gas and electric energy consumption and improves working efficiency and forging quality.

The invention discloses a fixed type three-side blown melting furnace structure, which is an improvement of a melting furnace, and is characterized in that high density oxygen-rich air is blown in the furnace from three directions of two sides of a three-side blown melting furnace and a termination part for participating in a melting reaction, the invention also discloses a production technology for melting oxygen-rich side-blowing molten pool copper and sulfonium, the production technology comprises the following steps: 1) proportioning of furnace charge; 2)melting by the high oxygen-rich three-side blown melting furnace; and 3) flotation of furnace slag. According to the invention, the currently used oxygen-rich side blowing melting furnace employs the technology that high silicon calcium three-component system slag and melting furnace slag pass through an electric furnace depletion treatment, two component system high iron slag and melting furnace slag employ a flotation treatment, high iron slag and melting furnace slag employ the flotation treatment during the melting process, so that the production technology has the advantages that the flux addition and fuel consumption are less, production and operation cost are low, slag output quantity and CO2 discharge capacity are less, environmental protection effect is good, copper comprehensive recovery rate is high, and melting intensity and production power of copper/sulfonium per unit area is high.

The invention relates to a preparation method of gear steel, in particular to a bar for a large wind driven generator gear and a manufacturing method of the bar. The bar comprises the following components of: 0.37-0.42 percent of C, 0.15-0.40 percent of Si, 0.80-1.25 percent of Cr, 0.50-0.90 percent of Mn, 0.15-0.30 percent of Mo, not more than 0.015 percent of S, 0.02-0.04 percent of Al, not more than 0.0015 percent of O, not more than 0.00020 percent of H, not more than 0.012 percent of P and the balance of Fe and unavoidable impurities. The manufacturing method comprises the steps of: adopting EAF (Electric Arc Furnace) and LF (Low Frequency) refining and VD (Vacuum Degassing) smelting, controlling aim carbon, aim phosphorus and tapping temperature of the electric arc furnace, adding synthetic slag, silicomangan and compound medium aluminum in a ladle in the tapping process for pre-deoxidizing; carrying out argon stirring in a refining process, fully deoxidizing, desulfurizing, removing impurities; treating for at least 10min under the vacuum degree of less than 0.5 torr of a VD furnace, feeding an Al wire after the vacuum is broken to control the content of the Al in the steelto be between 0.02 percent and 0.04 percent; and executing full-protection and low superheat degree pouring on continuous casting, adopting a medium-strength soft-pressing process on the solidified tail end, and adopting a heavy-pressing for carrying out rolling. The bar disclosed by the invention has high purity and compactness, and adapts to a complex and severe working environment of a wind power gear.

The invention specifically relates to titanium carbide powder and a preparation method thereof. According to a technical scheme, the preparation method comprises the following steps of: uniformly mixing 10-25 percent by weight of aluminum powder or magnesium powder, 0.5-2 percent of amorphous graphite powder or carbon black, 5-20 percent by weight of titanium dioxide and 60-80 percent by weight of a halide of lithium serving as raw materials; putting the uniformly-mixed raw materials into a tubular electric furnace, raising the temperature to 900-1,100 DEG C at the temperature raising rate of 2-8 DEG C per minute under the atmosphere of argon, and preserving heat for 1-5 hours; putting an obtained product into hydrochloric acid of which the concentration is 2-4 mol/L for soaking for 3-6 hours, filtering, and cleaning with deionized water till the pH value of a cleaning solution is 7.0; and drying at the temperature of 110 DEG C for 10-24 hours to obtain titanium carbide powder. The method has the characteristics of low reaction temperature, simple process, controllable synthesis process, low production cost, and the like; and the prepared titanium carbide powder has the characteristics of high crystallization, high product purity, freeness from an impure phase and powder particle size of 100-400 nanometers.

The invention discloses a furnace group energy consumption system and a method in a fused magnesia smelting process and belongs to the field of electric furnace energy consumption management. The furnace group energy consumption system comprises a database server, an application server, a client and a data collecting programmable logic controller (PLC). The application server comprises a data collecting module, an energy consumption index decomposition module, an energy consumption operation monitoring module and an energy consumption statistic analysis module. A general energy consumption index of the whole factory in the very day is calculated based on a production index issued by a superior, a historical statistic unit energy consumption value and an energy saving index and decomposed into energy consumption index values in all time intervals of all fused magnesia furnaces in a detailed mode. Energy consumption data of all the electric furnaces are collected in real time, and when an actual value exceeds the index value, warning information is sent to a manager so as to aid the manager to manage fused magnesia furnace energy consumption. In addition, electricity utilization links of empty burning, irregular operation and the like can be found for the manager through the analysis of the real-time energy consumption data, and the manager can be aided to perform energy consumption supervision and management.

The invention discloses an operation technology for an electric furnace converter. A furnace burden structure containing 85-95% of molten iron and 5-15% of steel scrap is adopted; after a furnace lid of an electric furnace is opened, the steel scrap is added at one time through a material basket; molten iron is continuously blended at a speed of 2.0-4.0 tons per minute by utilizing an iron blending device, and meanwhile, an oxygen flow is jetted into the furnace through three furnace-wall praxair carbon oxygen guns which are mounted on the furnace wall; the oxygen supply strength is adjusted according to a blowing condition in the furnace and the carbon content in the furnace stabilized at 0.40-0.80% is ensured; lime, return mine and limestone are added while oxygen is blown; slagging is performed and temperature of the molten steel in the furnace is adjusted; during a blowing process, the temperature of the molten steel in the electric furnace is controlled within a range of 1500 DEGC to 1560 DEG C and the stability of carbon oxygen reaction in the furnace is ensured; and the temperature of the molten steel is controlled within the range of 1600 DEG C to 1650 DEG C at end point of the electric furnace, thereby finishing electric furnace smelting. According to the operation technology provided by the invention, the problems of serious splashing and difficulty in dephosphorization of electric furnace converter production are solved, the splashing is light, the time of electric furnace smelting is short, and energy conservation and cost reduction are realized.

The invention belongs to the field of metallurgy of nonferrous metal, and particularly relates to a method for producing ferronickel or nickel matte through combined treatment of laterite by a rotary kiln and a direct current electric furnace. The method comprises the following steps of: adding the crushed laterite with granularity of 10-80 mm into a carbon reducing agent in an amount which is 1-16 percent by weight of the laterite; feeding into the rotary kiln for drying and pre-reducing; controlling tail gas CO content of the rotary kiln within a range of 0.5 percent to 1 percent of the total weight of materials in the kiln, temperature in the kiln within the range of 700 DEG C to 1,150 DEG C and roasting time within the range of 0.5 h to 2.0 h; and directly feeding pre-reduced hot materials into a direct currentore-smelting electric furnace for smelting to produce ferronickel or nickel matte. The method has the advantages of simple process flow, saving in equipment investment and capabilities of solving the problems of full utilization of material sensible heat and the like due to direct feeding of the high-temperature materials into the furnace, further reducing energy consumption and obviously improving economy of treating low-grade laterite.

The invention belongs to the technical field of purification and production of zinc sulfate solutions, and particularly relates to a method for reducing the zinc powder consumption in the process of purifying a zinc sulfate solution. The method comprises the following process steps: (1) in the state of stirring, heating liquid supernatant in the zinc sulfate solution to 50-60 DEG C; (2) adjusting the pH value of the solution to be 1-4.5; (3) adding a theoretical amount of electric furnace zinc powder required by a replacement reaction, and removing copper and cadmium in the solution, wherein the reaction time is 30-60 min; and (4) after the reaction is completed, filtering the obtained solution to obtain copper-cadmium-removed liquid and copper-cadmium residues, conveying the copper-cadmium-removed liquid to a deep purified cobalt nickel removal section to process, and further comprehensively recovering valuable metals from the copper-cadmium residues. The method disclosed by the invention is used for solving the problem that zinc powder in the process of purifying the zinc sulfate solution is excessive; the method is simple and practical in operation; and the cost of the electric furnace zinc powder can be saved by over 50%, therefore, the method has remarkable economic benefits.

The invention relates to a low-yield-ratio and high-strength steel plate having 690-MPa-level yield strength. The steel plate is prepared from chemical components including 0.10%-0.20% of C, 0.10%-0.40% of Si, 0.90%-1.40% of Mn, less than or equal to 0.030% of Nb, less than or equal to 0.010% of V, less than or equal to 0.025% of Ti, 0.02%-0.06% of Al, less than or equal to 0.10% of Ni, less thanor equal to 0.10% of Cu, 0.10%-0.80% of Cr, 0.10%-0.70% of Mo, 0.001%-0.005% of B, 0.001%-0.005% of Ca, less than or equal to 0.015% of P, less than or equal to 0.003% of S, less than or equal to 0.002% of O, less than or equal to 0.004% of N, less than or equal to 0.0002% of H and the balance Fe. The steel plate adopts the tempered sorbite and bainite duplex structure. The yield strength Rp0.2 ishigher than or equal to 690 MPa, the tensile strength Rm is higher than or equal to 770 MPa, the yield ratio Rp0.2/Rm is lower than or equal to 0.88, the ductility A is higher than or equal to 16%, and the low-temperature impact Akv at subzero 40 DEG C is higher than or equal to 100 J. The manufacturing process includes steel making by the aid of a converter or an electric furnace, LF refinement,VD or RH vacuum degassing, Ca treatment, continuous casting, heating, rolling, primary quenching, secondary quenching and tempering.

The invention relates to a production method of a large-thickness high-toughness yield strength 1100 MPa-grade ultrahigh-strength steel plate. The production method comprises the technological processes of converter or electric furnace steelmaking, LF refining, VD or RH vacuum degassing, Ca treatment, continuous casting, casting blank slow cooling diffusion treatment, heating, rolling, steel plateslow cooling diffusion treatment, quenching and tempering. Slow cooling diffusion treatment is carried out by adopting casting blank and steel plate offline residual heat. The casting blank slow cooling diffusion starting temperature is controlled to be 600-700 DEG C, the diffusion time is longer than or equal to 48 hours, and the diffusion ending temperature is smaller than or equal to 300 DEG C; the diffusion starting temperature of the steel plate is greater than or equal to 300 DEG C and the diffusion time is greater than or equal to 24 hours. By means of the two slow cooling diffusion processes, the content of harmful gas in the finished steel plate is greatly reduced, distribution of different chemical elements is homogenized, generation of internal stress of the steel plate is reduced, and a good foundation is laid for improving the ultralow-temperature impact toughness of the steel plate and the uniformity of the performance in the thickness direction.