Vacuum Treatment Of Molten Iron(fe) Patents (Class 75/508)
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Patent number: 11787956Abstract: The present invention provides a magnetic multilayer pigment flake and a magnetic coating composition that are relatively safe for human health and the environment. The pigment flake includes one or more magnetic layers of a magnetic alloy and one or more dielectric layers of a dielectric material. The magnetic alloy is an iron-chromium alloy or an iron-chromium-aluminum alloy, having a substantially nickel-free composition. The coating composition includes a plurality of the pigment flakes disposed in a binder medium.Type: GrantFiled: September 12, 2022Date of Patent: October 17, 2023Assignee: VIAVI SOLUTIONS INC.Inventors: Vladimir P. Raksha, Paul T. Kohlmann, Cornelis Jan Delst, Paul G. Coombs
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Patent number: 11684970Abstract: An immersion sensor is configured to determine the content of a chemical element in molten metal. The immersion sensor has an auxiliary electrochemical cell extending from an interior surface into the internal volume of a sampling chamber. The sampling chamber can be integrally-formed in a sensor head or in a separate refractory structure. The immersion sensor may be configured for the flow of molten metal into the internal volume of the sampling chamber and into contact with the auxiliary electrochemical cell.Type: GrantFiled: October 5, 2018Date of Patent: June 27, 2023Assignee: Vesuvius Refratarios Ltda.Inventors: Peterney Sasso, Ezequias Jose De Souza
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Patent number: 10147528Abstract: A non-oriented electrical steel sheet with fine magnetic performance, and a calcium treatment method therefor, including an RH (Ruhrstahl-Heraeus) refinement step. The RH refinement step sequentially comprises a decarbonization step, an aluminum deoxidation step, and a step of adding calcium alloy. In the step of adding calcium alloy, time when the calcium alloy is added satisfies the following condition: time interval between Al and Ca/total time after ?Al=0.2-0.8. In this method, production cost is reduced, the production process is simple, a normal processing cycle of RH refinement is not affected, the device is convenient in operation and is controllable, and foreign substances are controllable in both shape and quantities. The non-oriented electrical steel sheet prepared according to the present invention has fine magnetic performance, and the method can be used for mass production of the non-oriented electrical steel sheet with fine magnetic performance.Type: GrantFiled: March 27, 2012Date of Patent: December 4, 2018Assignee: Boashan Iron & Steel Co., LTDInventors: Feng Zhang, Xiandong Liu, Shishu Xie, Xuejun Lu, Xiao Chen, Aihua Ma, Peili Zhang, Yanwei Wang, Lan Zhang, Hongxu Hei
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Patent number: 8709123Abstract: The invention relates to a method of fabricating a stainless martensitic steel, comprising a step of electroslag remelting of an ingot of said steel then a step of cooling said ingot. Before the electroslag remelting step, the ingot undergoes vacuum degassing for a time that is sufficient to obtain a hydrogen content in the ingot of less than 3 ppm.Type: GrantFiled: October 11, 2010Date of Patent: April 29, 2014Assignee: SNECMAInventors: Laurent Ferrer, Patrick Philipson
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Publication number: 20140096648Abstract: A method for controlling A-shaped segregation of steel ingot. The method includes: 1) controlling a content of phosphorus in liquid steel at less than or equal to 0.005 wt. % upon tapping from an electric furnace, preventing steel slag from entering a ladle, controlling content of harmful elements at less than or equal to 100 ppm; and adding between 3 and 15 kg of calcium oxide and less than or equal to 0.5 kg of aluminum to each ton of the liquid steel; 2) pre-deoxidizing the liquid metal using vacuum carbon deoxidation; 3) de-sulfurizing, controlling content of oxygen, and controlling the content of sulfur in the liquid steel at less than or equal to 0.005 wt. %; and 4) performing vacuum degasification, controlling the total oxygen content at less than or equal to 15 ppm; and casting the steel in the presence of inert gas or in vacuum.Type: ApplicationFiled: December 12, 2013Publication date: April 10, 2014Applicant: INSTITUTE OF METAL RESEARCH CHINESE ACADEMY OF SCIENCESInventors: Dianzhong LI, Paixian FU, Hongwei LIU, Lijun XIA, Yiyi LI
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Patent number: 8557014Abstract: A carbonaceous-based metallizing method and apparatus wherein a metallic oxide is converted into a carbon-containing, metallized intermediate that is melted in an induction channel furnace to produce liquid metal from said metallic oxide. In the application of iron ore in the form of fines or concentrate, using low-cost coal will greatly reduce capital and operating costs by virtue of eliminating agglomeration of ore, cokemaking, and blast furnace operation. The liquid iron so produced is efficiently converted into steel in a steelmaking furnace such as a basic oxygen furnace (BOF), especially when it is physically integrated to the induction channel furnace wherein the liquid iron is directly poured into the integrated BOF by the induction channel furnace, producing low-cost steel, little heat loss, and minimum emissions.Type: GrantFiled: January 28, 2011Date of Patent: October 15, 2013Inventors: Albert Calderon, Terry James Laubis, Richard Owen McCarthy
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Patent number: 8523977Abstract: A method of desulfurizing steel including steps of forming a slag over a molten metal, drawing a vacuum to less than 5 torr over the slag and molten metal, stirring the molten metal and slag, and deoxidizing and desulfurizing the molten metal and slag to degas the steel reducing at least sulfur, nitrogen, oxygen, and hydrogen contents, and reducing activity of oxygen in the molten metal to less than 30 ppm. The method includes forming a slag composition after degassing the steel comprising CaO between about 50 and 70% by weight, SiO2 between about 20 and 28% by weight, CaF2 between about 5 and 15% by weight, MgO not more than 8% by weight, Al2O3 not more than 1% by weight, and a combination of FeO+MnO not more than 2% by weight, where the sum of CaO+CaF2+SiO2+MgO is at least 85% by weight.Type: GrantFiled: May 12, 2011Date of Patent: September 3, 2013Assignee: Nucor CorporationInventors: Dhiren Panda, Neal Ross, Gary McQuillis, Jerome Jenkins
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Patent number: 8313553Abstract: A method of making a steel with low carbon less than 0.035% by weight including steps of preparing a heat of molten steel composition in a steelmaking furnace to a tapping temperature as desired for desulfurization at a VTD, tapping open into a ladle the molten steel composition with an oxygen level between about 600 and 1120 ppm, providing slag forming compound to the ladle to form a slag cover over the molten steel composition in the ladle, transporting the molten steel composition in the ladle to a VTD, decarburizing the molten steel composition at the VTD by drawing a vacuum of less than 650 millibars, after decarburizing, adding one or more deoxidizers to the molten steel composition and deoxidizing the molten steel composition, after deoxidizing, adding one or more flux compounds to desulfurize the molten steel composition, and casting the molten steel composition to form a steel with low carbon less than 0.035% by weight.Type: GrantFiled: March 30, 2009Date of Patent: November 20, 2012Assignee: Nucor CorporationInventors: Jacobus Marthinus Andreas Geldenhuis, David John Sosinsky, Daniel Gene Murray, David Wayne McGaughey, Eugene B. Pretorius
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Patent number: 8303734Abstract: The present invention provides a high strength thick steel material excellent in toughness and weldability reduced in amount of C and amount of N, containing suitable amounts of Si, Mn, Nb, Ti, B, and O, having contents of C and Nb satisfying C—Nb/7.74?0.004, having a density of Ti-containing oxides of a particle size of 0.05 to 10 ?m of 30 to 300/mm2, and having a density of Ti-containing oxides of a particle size over 10 ?m of 10/mm2 or less, produced by treating steel by preliminary deoxidation to adjust the dissolved oxygen to 0.005 to 0.015 mass %, then adding Ti and, furthermore, vacuum degassing the steel for 30 minutes or more, smelting it, then continuously casting it to produce a steel slab or billet, heating the steel slab or billet to 1100 to 1350° C., hot rolling the slab or billet to a thickness of 40 to 150 mm, then cooling it.Type: GrantFiled: September 26, 2008Date of Patent: November 6, 2012Assignee: Nippon Steel CorporationInventors: Suguru Yoshida, Hiroshi Kita, Teruhisa Okumura, Hirokazu Sugiyama, Teruyuki Wakatsuki
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Patent number: 8221521Abstract: To degas a molten metal, a receptacle containing the molten metal and a layer of slag over the molten metal is positioned in a chamber, and the chamber is evacuated. As the pressure in the chamber reduces, gas is generated at the interface between the molten metal and the slag, which causes the slag to foam. To inhibit overflowing of slag from the receptacle, a gauge outputs a signal indicative of the level of the surface of the slag, and the rate of evacuation of the chamber is reduced to reduce the rate of gas generation.Type: GrantFiled: September 10, 2010Date of Patent: July 17, 2012Assignee: Edwards LimitedInventor: Simon Harold Bruce
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Publication number: 20120055288Abstract: A process for making a precipitation hardenable stainless steel alloy is described. The process includes the step of melting a martensitic steel alloy having the following composition in weight percent, about Carbon ?0.03 max. Manganese ?1.0 max. Silicon ?0.75 max. Phosphorus 0.040 max. Sulfur 0.020 max. Chromium 10-13 Nickel 10.5-11.6 Titanium 1.5-1.8 Molybdenum 0.25-1.5? Copper ?0.95 max. Aluminum ?0.25 max. Niobium ?0.3 max. Boron 0.010 max. Nitrogen 0.030 max. and the balance being iron and usual impurities. The process also includes the step of adding calcium to the alloy while molten. The calcium combines with available sulfur and oxygen to form calcium base inclusions selected from the group consisting of calcium sulfides, calcium oxides, calcium oxysulfides, and combinations thereof. In a further step, the alloy is processed to remove at least a portion of the calcium base inclusions. The alloy is then solidified.Type: ApplicationFiled: November 10, 2011Publication date: March 8, 2012Inventors: Robert Wayne Krieble, William Joseph Martin, Thomas Constantine Zogas, David Elmer Wert, Paul Michael Novotny
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Patent number: 8105415Abstract: A method of making a steel with low carbon less than 0.035% by weight including steps of preparing a heat of molten steel composition in a steelmaking furnace to a tapping temperature as desired for desulfurization at a VTD, tapping open into a ladle the molten steel composition with an oxygen level between about 600 and 1120 ppm, providing slag forming compound to the ladle to form a slag cover over the molten steel composition in the ladle, transporting the molten steel to a VTD, decarburizing the molten steel composition at the VTD by drawing a vacuum of less than 650 millibars, after decarburizing, transporting the molten steel to an LMF and deoxidizing the molten steel composition, after deoxidizing, returning to the VTD to desulfurize and degas the molten steel composition, and casting the molten steel composition to form a steel with low carbon less than 0.035% by weight.Type: GrantFiled: June 18, 2010Date of Patent: January 31, 2012Assignee: Nucor CorporationInventors: Gary McQuillis, Jerome Jenkins, Neal Ross, Dhiren Panda, David John Sosinsky
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Patent number: 8048197Abstract: The present invention provides a low carbon steel sheet and a low carbon steel slab on which formation of surface defects can be surely prevented by preventing aggregation of inclusions in the molten steel and finely dispersing inclusions in the steel sheet or slab, and a process for producing the steel sheet and slab. The present invention provides a process comprising the steps of decarburizing a molten steel so as to produce a carbon concentration of up to 0.01% by mass, pre-deoxidizing the molten steel by adding Al thereto so as to produce a dissolved oxygen concentration from 0.01 to 0.04% by mass, adding thereto Ti and at least La and/or Ce, and casting the molten steel, and a steel sheet and a steel slab obtained by the process.Type: GrantFiled: February 15, 2008Date of Patent: November 1, 2011Assignee: Nippon Steel CorporationInventors: Katsuhiro Sasai, Wataru Ohashi, Tooru Matsumiya, Yoshiaki Kimura, Junji Nakashima
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Patent number: 7998237Abstract: Disclosed are a method and an installation for producing steel products (1) having an optimum surface quality, especially extremely low carbon contents (UCL steel or IF steel), nitrogen contents, total oxygen contents, high-strength or stainless steel qualities.Type: GrantFiled: May 25, 2004Date of Patent: August 16, 2011Assignee: SMS Siemag AktiengesellschaftInventors: Fritz-Peter Pleschiutschnigg, Karl-Ernst Hensger, Dieter Rosenthal, Rainer Teworte, Dieter Tembergen
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Patent number: 7955413Abstract: A method for producing Transformation Induced Plasticity (TRIP) steels comprises adding a degassing step to remove hydrogen and nitrogen prior to casting, resulting in a more fluid steel that exhibits improved castability.Type: GrantFiled: April 18, 2008Date of Patent: June 7, 2011Assignee: United States Steel CorporationInventors: Jeffrey J. Becker, Gerald E. Goldsmith, Simon N. Rodich, William K. Schlichting, Michael S. Wukich
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Publication number: 20110094336Abstract: The invention relates to a method for producing a steel melt containing up to 30% of Mn, which additionally may comprise up to 5% Si, up to 1.5% C, up to 22% Al, up to 25% Cr, up to 30% Ni, and up to 5% each of Ti, V, NB, Cu, Sn, Zr, Mo, and W, and up to 1% each of N and P, with the remainder being iron and unavoidable steel companion elements.Type: ApplicationFiled: November 17, 2008Publication date: April 28, 2011Applicants: SALZGITTER FLACHSTAHL GMBH, PEINER TRAGER GMBHInventors: Karl-Heinz Spitzer, Christian Redeker
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Patent number: 7828873Abstract: A direct smelting vessel (3) for operating a molten bath-based direct smelting process under pressure conditions in the vessel is disclosed. The vessel includes a forehearth (67) for tapping molten metal continuously from the vessel. The forehearth includes an open connection (97) that extends through a side wall of the vessel into the interior of the vessel. The open connection is formed to dampen the impact of sudden changes in pressure in the vessel on molten metal flow in the forehearth that could result in an undesirable surge of molten metal from the forehearth. The open connection is also formed so that molten metal does not freeze in the connection for at least 6 hours when molten metal is not being discharged from the vessel into the forehearth via the open connection.Type: GrantFiled: April 26, 2006Date of Patent: November 9, 2010Assignee: Technological Resources Pty. LimitedInventor: Matthew John Gurr
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Publication number: 20100126311Abstract: A method for producing liquid ferroalloy by direct processing of manganese and chromium bearing iron compounds, by the steps: of mixing carbonaceous reductant, fluxing agent, and a binder with materials such as iron sands, metallic oxides, manganese-iron ore concentrates and/or chromium-iron ore concentrates and silica sands, to form a mixture; forming agglomerates from the mixture; feeding the agglomerates to a melting furnace with other materials; melting the feed materials at a temperature of from 1500 to 1760 C and forming a slag and hot metal; removing the slag; and tapping the hot metal as liquid ferroalloy.Type: ApplicationFiled: August 12, 2008Publication date: May 27, 2010Inventor: Glenn E. Hoffman
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Publication number: 20100024596Abstract: A method of making a steel with low carbon less than 0.035% by weight including steps of preparing a heat of molten steel composition in a steelmaking furnace to a tapping temperature as desired for desulfurization at a VTD, tapping open into a ladle the molten steel composition with an oxygen level between about 600 and 1120 ppm, providing slag forming compound to the ladle to form a slag cover over the molten steel composition in the ladle, transporting the molten steel composition in the ladle to a VTD, decarburizing the molten steel composition at the VTD by drawing a vacuum of less than 650 millibars, after decarburizing, adding one or more deoxidizers to the molten steel composition and deoxidizing the molten steel composition, after deoxidizing, adding one or more flux compounds to desulfurize the molten steel composition, and casting the molten steel composition to form a steel with low carbon less than 0.035% by weight.Type: ApplicationFiled: March 30, 2009Publication date: February 4, 2010Applicant: NUCOR CORPORATIONInventors: Jacobus Marthinus Andreas Geldenhuis, David John Sosinsky, Daniel Gene Murray, David Wayne McGaughey, Eugene B. Pretorius
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Patent number: 7597737Abstract: A method for producing a steel ingot, which comprises an Mg oxide forming step of preparing a molten steel containing Mg in an amount sufficient for the molten steel to have an oxide composition having MgO as a primary component and a dissociation step of keeping the pressure of the atmosphere around the molten steel to be lower than that in the Mg oxide forming step, to thereby dissociate MgO to Mg and oxygen and reduce the content of Mg in the steel to 50% or less of that in the Mg oxide forming step through the diffusion thereof into a gas phase. A preferred method further involves a solidifying step.Type: GrantFiled: April 30, 2004Date of Patent: October 6, 2009Assignee: Hitachi Metals, Ltd.Inventors: Ken-ichiro Hara, Hidemi Takao, Setsuo Mishima, Etsuo Fujita
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Publication number: 20080257110Abstract: A method for producing Transformation Induced Plasticity (TRIP) steels comprises adding a degassing step to remove hydrogen and nitrogen prior to casting, resulting in a more fluid steel that exhibits improved castability.Type: ApplicationFiled: April 18, 2008Publication date: October 23, 2008Inventors: Jeffrey J. Becker, Gerald E. Goldsmith, Simon N. Rodich, William K. Schlichting, Michael S. Wukich
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Patent number: 7396378Abstract: A process for producing a high-cleanliness steel is provided which can produce, without relying upon a high-cost remelting process, steel products having cleanliness high enough to satisfy requirements for properties of mechanical parts used under severe environmental conditions. The production process comprises the steps of: transferring a molten steel produced in an arc melting furnace or a converter to a ladle furnace to refine the molten steel; subjecting the molten steel to circulation-type degassing; and casting the molten steel into an ingot, wherein, in transferring the molten steel to the ladle furnace, a deoxidizer including aluminum and silicon, is added to previously deoxidize the molten steel, that is, to perform tapping deoxidation before refining in the ladle refining furnace.Type: GrantFiled: June 5, 2001Date of Patent: July 8, 2008Assignee: Sanyo Special Steel Co., Ltd.Inventors: Ichiro Sato, Kaichiro Ishido, Tomomi Mori, Toshihiro Irie, Kazuya Kodama, Kiyoshi Kawakami, Shuhei Kitano
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Patent number: 7250071Abstract: A new austenitic stainless steel containing approximately 0.1-1.0 mass % of Si and not more than approximately 0.003 mass % of Al. Nonmetallic inclusions dispersed in a steel matrix are converted to MnO—SiO2—Al2O3 containing not less than approximately 15 mass % of SiO2 and not more than approximately 40 mass % of Al2O3. During steel making, molten steel is covered with basic slag and heavily deoxidized with a Si alloy whose Al content is controlled to not more than approximately 1.0 mass % in a vacuum or non-oxidizing atmosphere. The austenitic stainless steel sheet can be formed to an objective shape without the occurrence of cracking due to its decrease in susceptibility to cracking and its good formability.Type: GrantFiled: July 13, 2004Date of Patent: July 31, 2007Assignee: Nisshin Steel Co., Ltd.Inventors: Junichi Katsuki, Teruyoshi Iida, Takashi Yamauchi, Satoshi Suzuki, Naoto Hiramatsu
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Patent number: 7150777Abstract: A method and apparatus for the recovery of by product gases used in a vacuum metal treatment process or other gas treatments processes are disclosed. The present invention is normally carried out in a process chamber in the last stage of the process, after vacuum processing. The chamber is filled with an inert gas for cooling down the processed metal or other materials load at a certain predetermined pressure. The chamber is connected to a receiver having a pressure control device and a mechanism capable of changing its volume in order to keep constant pressure during the passage of gas from the chamber into the receiver. In addition, there is a cooling or heat transfer device to reduce the recovering gas temperature between the chamber and the receiver. The gas flow is driven by the excess pressure in the chamber during a first transfer period, or by the vacuum pumping system during the last gas transfer period.Type: GrantFiled: April 25, 2003Date of Patent: December 19, 2006Assignee: Ciateq A.C.Inventor: Miguel Angel Alcantara
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Patent number: 7094273Abstract: A steel article is fabricated by providing an iron-base alloy having less than about 0.5 weight percent aluminum, melting the alloy to form a melt, adding calcium to the melt, thereafter adding aluminum to the melt to increase the aluminum content of the melt to more than about 0.5 weight percent aluminum, and casting the melt to form a casting. Other calcium additions may be made simultaneously with the adding of aluminum, and after the adding of aluminum but before casting the melt. The calcium additions deoxidize the melt to minimize the formation of clustered aluminum-oxygen-based inclusions.Type: GrantFiled: February 6, 2004Date of Patent: August 22, 2006Assignee: General Electric CompanyInventors: Edward Lee Raymond, Mark Alan Rhoads, Glenn Charles Culbertson
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Publication number: 20040211296Abstract: A method and apparatus for the recovery of by product gases used in a vacuum metal treatment process or other gas treatments processes are disclosed. The present invention is normally carried out in a process chamber in the last stage of the process, after vacuum processing. The chamber is filled with an inert gas for cooling down the processed metal or other materials load at a certain predetermined pressure. The chamber is connected to a receiver having a pressure control device and a mechanism capable of changing its volume in order to keep constant pressure during the passage of gas from the chamber into the receiver. In addition, there is a cooling or heat transfer device to reduce the recovering gas temperature between the chamber and the receiver. The gas flow is driven by the excess pressure in the chamber during a first transfer period, or by the vacuum pumping system during the last gas transfer period.Type: ApplicationFiled: April 25, 2003Publication date: October 28, 2004Inventor: Miguel Angel Alcantra
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Publication number: 20040154437Abstract: Molten steel is degasified under vacuum and in the first 5 minutes of the degasification to improve and accelerate the degasification solids in the form of pieces of a size of 2 to 50 mm are introduced into the melt.Type: ApplicationFiled: December 4, 2003Publication date: August 12, 2004Applicant: SMS Mevac GmbHInventors: Rainer Dittrich, Rainer Teworte, Dieter Tembergen
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Patent number: 6764528Abstract: A method of producing a high nitrogen, ultra low carbon steel suitable to rolling material for use in cold rolled steel sheets having excellent age hardening property by an age hardening treatment after forming by working, with no defects in slabs or steel sheets, reliably, at a reduced cost and with a high productivity is proposed. The method for producing a rolling material for use in ultra low carbon steel sheets at: C≦0.0050 mass % comprises; applying primary decarburization refining to molten iron from a blast furnace, then controlling the composition in the molten steel after primary decarburization refining to a range satisfying the following relation: [mass % N]−0.15[mass % C]≧0.0060, subsequently conducting secondary decarburization refining to a ultra low carbon concentration region while suppressing denitridation using a vacuum degassing facility, then conducting deoxidation by Al and, further, controlling the composition.Type: GrantFiled: August 8, 2002Date of Patent: July 20, 2004Assignee: JFE Steel CorporationInventors: Seiji Nabeshima, Shuji Takeuchi, Hisashi Ogawa, Yuki Nabeshima, Yasuyuki Masumoto
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Patent number: 6692550Abstract: A steel article is fabricated by providing an iron-base alloy having less than about 0.5 weight percent aluminum, melting the alloy to form a melt, adding calcium to the melt, thereafter adding aluminum to the melt to increase the aluminum content of the melt to more than about 0.5 weight percent aluminum, and casting the melt to form a casting. Other calcium additions may be made simultaneously with the adding of aluminum, and after the adding of aluminum but before casting the melt. The calcium additions deoxidize the melt to minimize the formation of clustered aluminum-oxygen-based inclusions.Type: GrantFiled: March 28, 2002Date of Patent: February 17, 2004Assignee: General Electric CompanyInventors: Edward Lee Raymond, Mark Alan Rhoads, Glenn Charles Culbertson
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Publication number: 20010006012Abstract: A rotary furnace apparatus is provided for rapid melting of a variety of virgin and recycled ferrous and non-ferrous metals, which distributes the introduction of the unmelted charge materials and hence the melting heat requirements along an elongate gas-solid-liquid reaction zone within the furnace, according to the distribution of heat available to effect melting. In the case of fine-sized metal charge materials, fluxes and additive reagents, a longitudinally traversing solids injection lance projecting into the furnace is provided with nozzle directed to project a jet of charge down into the bath as it traverses successively backwards and forwards. A traversing oscillating conveyor is provided for coarse-sized scrap metals and the like.Type: ApplicationFiled: March 2, 2001Publication date: July 5, 2001Inventor: William Lyon Sherwood
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Patent number: 6117389Abstract: Titanium killed steel sheets which are not troubled by nozzle clogging while they are produced in a continuous casting process, have few surface defects caused by cluster-type inclusions, and are highly rust resistant, and are formed from a melt of titanium killed steel that contains any one or two of Ca and metals REM in an amount of not smaller than 0.0005% by weight, and wherein the steel contains major oxide inclusions of any one or two of CaO and REM oxides in an amount of from about 5 to 50% by weight, Ti oxides in an amount of not larger than about 90% by weight, and Al.sub.2 O.sub.3 in an amount of not larger than about 70% by weight.Type: GrantFiled: September 24, 1998Date of Patent: September 12, 2000Assignee: Kawasaki Steel CorporationInventors: Seiji Nabeshima, Hirokazu Tozawa, Kenichi Sorimachi
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Patent number: 6042633Abstract: A method for after combustion of reaction gases resulting from the decarburization of liquid steel in reaction vessels under vacuum includes the steps of arranging a blow-in opening within a refractory lining of a reaction vessel and introducing an air stream, comprised of hot air of a temperature between 800.degree. C. to 1400.degree. C., counter to the flow direction of the reaction gases via the blow-in opening into the reaction vessel. A device for performing after combustion of reaction gases resulting from the decarburization of liquid steel in a reaction vessel under vacuum includes a generator, connected to the reaction vessel, for producing hot air. The generator contains a bulk of balls for heating the air guided through the bulk of balls and subsequently introduced into the reaction vessel. The bulk of balls consists of a refractory material and is heated by heat energy.Type: GrantFiled: November 26, 1997Date of Patent: March 28, 2000Assignee: Technometal Gesellschaft fur Metalltechnologie mbHInventors: Karl Brotzmann, Heinz Holtermann
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Patent number: 5938975Abstract: Process of producing power comprising:providing a turbine adapted to generate shaft work, said turbine having a combustor; and a rocket engine having a nozzle and a compressor means;feeding fuel and oxidant to the rocket engine and the rocket engine compressor means;feeding carbonaceous matter and steam into the rocket engine nozzle;processing the output of the rocket engine nozzle into fuel for the turbine;introducing said fuel and oxidant for the turbine to the turbine combustor; andrecycling a substantial portion of the hot exhaust from the turbine to the rocket engine compressor means; andcontrolling the inlet temperature to the turbine.Apparatus for producing power comprising a rocket engine and a turbine adapted to generate shaft work is also disclosed.Type: GrantFiled: December 23, 1996Date of Patent: August 17, 1999Inventors: Bernard Ennis, Anthony Cirrito
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Patent number: 5917115Abstract: A method of and apparatus for degassing molten metal in a vacuum treatment chamber defined by a open topped ladle containing the molten metal and a generally cylindrical refractory lined cover having a closed top and an open bottom positioned on the ladle, with a temporary joint formed therebetween, and a vacuum seal sealing the vacuum treatment chamber from the atmosphere. A vacuum offtake is connected to the cover chamber to apply vacuum to the vacuum treatment chamber, and the molten metal is stirred to produce sufficient turbulence and splashing to produce an increased surface area of molten metal exposed to vacuum to accelerate the degassing rate. The offtake outlet is located at a height above the cover chamber open bottom to substantially prevent splashed metal and slag from being carried into the offtake while permitting aggressive stirring to increase treatment rate.Type: GrantFiled: May 12, 1998Date of Patent: June 29, 1999Assignee: SMS Vacmetal, GmbHInventor: Erich F. Wondris
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Patent number: 5902374Abstract: The present invention relates to a molten steel refining method for refining molten steel, the carbon content of which is not more than 0.1 weight %, by blowing oxygen gas for decarburization at a blowing speed so that a cavity, the depth of which is 150 to 400 mm, can be formed on the surface of molten steel in a straight barrel type vacuum refining apparatus in which a straight barrel type vacuum vessel having no vessel bottom and a ladle are arranged.Type: GrantFiled: March 28, 1997Date of Patent: May 11, 1999Assignee: Nippon Steel CorporationInventors: Shinya Kitamura, Kimitoshi Yonezawa, Kenichiro Miyamoto, Shinji Sasakawa, Kunihiko Fujiwara
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Patent number: 5853659Abstract: Steel having excellent workability and deep drawability is produced by an electric furnace-vacuum degassing process. The steel has a composition which comprises about:C: 0.0050 wt % or lessSi: 1.5 wt % or lessMn: 1.5 wt % or lessP: 0.10 wt % or lessAl: 0.10 wt % or lessS: 0.020 wt % or lessO: 0.01 wt % or lessCu: 0.02-1.5 wt %Ni: 0.02-2.0 wt %Ti and/or Nb: from 0.001 to 0.10 wt %N: from 0.0040 to 0.0090 wt %.Type: GrantFiled: February 26, 1997Date of Patent: December 29, 1998Assignee: Kawasaki Steel CorporationInventors: Takashi Sekita, Taro Yahiro, Saiji Matsuoka, Toshio Fujimura, Takemi Yamamoto, Masahiko Morita, Osamu Furukimi, Arata Ueda
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Patent number: 5520718Abstract: A method for degassing molten steel comprises the use of a lift gas which includes carbon dioxide. The inventive method includes providing a reaction zone isolated from the ambient atmosphere, and providing a bath of molten steel, at least a portion of which is located in the reaction zone. The pressure is reduced in the reaction zone to a sub-atmospheric pressure. A gas comprising carbon dioxide is supplied to the bath of molten steel in order to vertically circulate the molten steel. The method also preferably includes (a) supplying carbon dioxide, e.g., with a tuyere, to the reaction zone and (b) supplying carbon dioxide to the bath of molten steel, e.g., by gas bubbling or stirring. An apparatus for performing the method steps is also disclosed.Type: GrantFiled: September 2, 1994Date of Patent: May 28, 1996Assignee: Inland Steel CompanyInventors: Leonard M. Keilman, William F. Flanagan, Jr., James E. Bradley, Shankverm R. Balajee
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Patent number: 5472479Abstract: A method of making ultra-low carbon, ultra-low sulfur content steel comprising introducing molten metal and slag into a vacuum decarburizer to reduce the carbon content of the metal to below 0.005%, followed by deoxidizing the molten steel, deoxidizing the slag and mixing the slag with the molten steel to reduce the sulfur content to below 0.005%.Type: GrantFiled: January 26, 1994Date of Patent: December 5, 1995Assignee: LTV Steel Company, Inc.Inventor: Kevin C. Ahlborg
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Patent number: 5435833Abstract: A process for converting a copper or nickel matte comprising at least 30% by weight of a copper or nickel based material and a substantial weight amount of an iron based material as one of the impurities to be removed from the matte by oxidation in a converter wherein during a first step of said process substantially all of the iron based material is oxidized with an oxygen comprising gas to make ferrous oxide which is thereafter transformed into slag by addition of a solid material to the molten metal and during a second step of said process, the copper based material is oxidized with said oxygen comprising gas to generate substantially pure copper and residues, said residues being essentially in gaseous form, the oxygen comprising gas being injected through an internal injector of a concentric shrouded tuyere comprising the internal injector and an external injector concentrically disposed around said internal injector with a gas passage therebetween, a shrouding substantially inert gas being injected throuType: GrantFiled: September 30, 1993Date of Patent: July 25, 1995Assignee: L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges ClaudeInventor: Alejandro A. Bustos
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Patent number: 5417739Abstract: A method of making stabilized ultra-low carbon steel having a high nitrogen content for enameling applications. The preferred method involves two phases. The first phase occurs in the basic oxygen furnace wherein nitrogen gas is combined with oxygen gas and blown into the melt through the oxygen lance. After the oxygen blow the carbon content of the melt is approximately 0.03% and the nitrogen content is at least about 0.016 to 0.020%. In the second phase the melt is introduced to a vacuum circulation decarburizer where the carbon content of the steel is reduced to ultra low levels on the order of 0.005%. The nitrogen content is maintained at a level of at least about 0.01% by introducing nitrogen gas into the vacuum decarburization vessel as the lift gas through inert gas tuyeres.Type: GrantFiled: December 30, 1993Date of Patent: May 23, 1995Assignee: LTV Steel Company, Inc.Inventors: Richard R. Watkins, Robert Blossey, Gregory Wotell
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Patent number: 5415834Abstract: A warm forging implement having high tensile strength, high abrasion resistance, high impact strength and high ductility and a composition within the following ranges:______________________________________ C .28-.36 Mn .40-1.00 P Usual S Usual Si up to .35 Ni 1.65-3.40 Cr .80-1.30 Mo .40-1.00 V .05-.15 ______________________________________and a method of manufacture thereof which includes either single or double vacuum treatment, the second vacuum treatment being vacuum arc remelting.Type: GrantFiled: January 19, 1994Date of Patent: May 16, 1995Assignee: A. Finkl & Sons Co.Inventors: Charles W. Finkl, Algirdas A. Underys
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Patent number: 5415680Abstract: Disclosed is a method and apparatus of treating molten metal for reducing the amount of gaseous or volatile material contained therein. The method comprises providing a body of molten metal and contacting the molten metal with a porous member having a porous surface resistant to penetration with the molten metal. The porous member is subjected to reduced pressure to impose a reduced pressure zone on the molten metal contacting the porous surface thereby removing the gaseous material from the molten metal through the porous member.Type: GrantFiled: November 9, 1992Date of Patent: May 16, 1995Inventor: C. Edward Eckert
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Patent number: 5413623Abstract: Molten steel is efficiently vacuum treated in a vacuum treatment vessel provided with a top blow lance capable of injecting oxygen and a gaseous fuel at desired flow rates, respectively, into the molten steel. The blow lance is provided on the top of the vacuum treatment vessel and is supported so as to be freely vertically movable. By spacing the lower end of the top blow lance not more than 2 m from the surface of the molten steel bath and injecting only oxygen onto the molten steel, and spacing the lower end of the top blow lance 1.0 m or more from the surface of the molten steel bath and injecting both oxygen and a gaseous fuel gas onto the molten steel, the temperature of the molten steel is prevented from decreasing during the vacuum treatment and the molten steel is so prevented from depositing on the inside wall of the vacuum treatment vessel.Type: GrantFiled: August 25, 1993Date of Patent: May 9, 1995Assignee: Nippon Steel CorporationInventors: Kazuo Oonuki, Teruyoshi Hiraoka, Hiroshi Nagahama, Kazuhisa Fukuda, Akira Nobumoto, Takahiro Isono, Atsumi Yamada, Hiroki Gofuku
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Patent number: 5387275Abstract: The invention relates to the field of metallurgy and to a method and a device for the extraction of zinc in solution in a liquid iron bath (2) held in a container (3), such as a crucible for the casting of foundry parts. It is characterized in that, before utilizing the bath for the casting of parts, in a first phase, the gas volume (7) situated in the container (3) is sealingly confined in the east iron bath (2) and, in a second phase, a variable partial vacuum is created in the confined atmosphere in a controlled way in order to constantly adjust it to a predetermined value as a function of the time evolution of the pressure of vapor saturating zinc in solution in the melt at the bath temperature; and said zinc is trapped.Type: GrantFiled: September 17, 1993Date of Patent: February 7, 1995Assignee: Ecole Centrale de LilleInventors: Jean C. Tissier, Jean Y. Dauphin, Pierre Perrot
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Patent number: 5374297Abstract: A furnace 10 for smelting iron ore and/or refining molten iron 20 is equipped with an overhead pneumatic lance 40, through which a center stream of particulate coal 53 is ejected at high velocity into a slag layer 30. An annular stream of nitrogen or argon 51 enshrouds the coal stream. Oxygen 52 is simultaneously ejected in an annular stream encircling the inert gas stream 51. The interposition of the inert gas stream between the coal and oxygen streams prevents the volatile matter in the coal from combusting before it reaches the slag layer. Heat of combustion is thus more efficiently delivered to the slag, where it is needed to sustain the desired reactions occurring there. A second stream of lower velocity oxygen can be delivered through an outermost annulus 84 to react with carbon monoxide gas rising from slag layer 30, thereby adding still more heat to the furnace.Type: GrantFiled: November 12, 1993Date of Patent: December 20, 1994Assignee: Steel Technology CorporationInventor: Mark R. Schlichting
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Patent number: 5356456Abstract: A method of degassing and decarburizing molten stainless steel in a vacuum, which molten steel is produced in a steel making furnace. Molten steel is foamed in a vacuum tank. Before foaming the [N] (%) in the molten steel is increased. The foam is produced by denitrification of the steel during vacuum degassing. Oxidizing gas is blown through a top-blow lance onto the surface of the steel in a vacuum tank, causing the reaction C+1/2O.sub.2 .fwdarw.CO to decarbonize the steel. Temperature decrease of the molten steel is resisted by combustion of CO produced by the reaction of C+1/2O.sub.2 .fwdarw.CO.Type: GrantFiled: October 5, 1993Date of Patent: October 18, 1994Assignee: Kawasaki Steel CorporationInventors: Hiroshi Nishikawa, Masanori Nishikohri, Hitoshi Ohsugi
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Patent number: 5343492Abstract: A crucible (9) surrounded by an induction coil (10) is housed for tilting about a first tilt axis within a gas-tight furnace chamber (2) which has a closable opening (40a) for transferring the melt (31) into a receiving vessel (36, 63). The furnace chamber (2) is in turn tiltable about a second tilt axis (A2) between a melting position and a position in which the start of the pouring of the melt is immediately imminent by an angle which corresponds to the range of the tilting angle of the crucible (9). The opening (40a) for transferring the melt is surrounded by a first sealing flange (41) which, after the tilting path of the furnace chamber (2) has been traveled, comes sealingly into contact with a second sealing flange (38, 64) of an additional gas-tight chamber (35, 61) in which the receiving vessel (36, 63) for the melt is situated.Type: GrantFiled: May 5, 1993Date of Patent: August 30, 1994Assignee: Leybold Durferrit GmbHInventor: Alfred Henn
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Patent number: 5252120Abstract: A method and apparatus for producing high quality steel having less than about 1 ppm H, 50 ppm N, 25 ppm O and 0.005 S which includes subjection to vacuum, gas purging, and alternating current heating arcs, followed by shrouded pouring into sealed ingot molds to form a VAR electrode which is subsequently remelted under a very low absolute vacuum and re-solidified.Type: GrantFiled: October 26, 1992Date of Patent: October 12, 1993Assignee: A. Finkl & Sons Co.Inventors: Charles W. Finkl, Guy A. Brada, Algirdas A. Underys
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Patent number: 5242484Abstract: A plant for secondary metallurgical processing of molten steel, having a melting apparatus and a continuous casting apparatus, a first station and a second station each having an associated evacuatable container for the molten steel, an oxygen feed device and an additive feed device. Each container receives a casting ladle, and has a vacuum-tight cover to provide a seal. A moderate vacuum device, e.g. a water ring pump and a high vacuum device, e.g. a water ring pump and a steam jet are provided, and are connected to the container via a device for selectively connecting the moderate vacuum device and the high vacuum device to the containers.Type: GrantFiled: May 4, 1992Date of Patent: September 7, 1993Assignee: Mannesmann AktiengesellschaftInventors: Georg Schonewolf, Jurgen Dorpinghaus, Horst Dieter Scholer
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Patent number: 5228902Abstract: A method for desulfurizing molten steel while the steel is subjected to a vacuum dehydrogenation treatment, comprising adding to the steel in a vacuum chamber a desulfurizing agent in lump form and comprising, by weight percent, about 50% CaO, about 38% CaF.sub.2, and about 10% MgO.Type: GrantFiled: September 3, 1992Date of Patent: July 20, 1993Assignee: USX CorporationInventors: Robert S. Bogan, Brad Hjerpe, Roger L. Marquart, James D. Reisinger