Hydrogen Patents (Class 148/634)
  • Patent number: 11946114
    Abstract: Provided is an annealing separating agent composition for a grain-oriented electrical steel sheet, a grain-oriented electrical steel sheet and a method for manufacturing a grain-oriented electrical steel sheet. The annealing separating agent composition for a grain-oriented electrical steel sheet according to an embodiment of the present invention contains 30 to 70% by weight of a calcium compound, and the remainder of magnesium oxide or magnesium hydroxide on a solid basis.
    Type: Grant
    Filed: December 14, 2021
    Date of Patent: April 2, 2024
    Assignee: POSCO CO., LTD
    Inventors: Min Serk Kwon, Tae Young No, Chang Soo Park, Heon-Jo Choi
  • Patent number: 11773464
    Abstract: A press hardening method includes the following steps providing a carbon steel sheet coated with a barrier pre-coating including nickel and chromium wherein the weight ratio Ni/Cr is between 1.5 and 9, cutting the sheet to obtain a blank, thermal treatment of the blank in an atmosphere having an oxidizing power equal or higher than that of an atmosphere consisting of 1% by volume of oxygen and equal or smaller than that of an atmosphere consisting of 50% by volume of oxygen, such atmosphere having a dew point between ?30 and +30° C., transfer of the blank into a press tool, hot-forming of the blank to obtain a part, cooling of the part to obtain a microstructure in steel being martensitic or martensito-bainitic or made of at least 75 wt. % of equiaxed ferrite, from 5 to 20 wt. % of martensite and bainite in amount less than or equal to 10 wt. %.
    Type: Grant
    Filed: September 20, 2019
    Date of Patent: October 3, 2023
    Assignee: ArcelorMittal
    Inventors: Pascal Drillet, Raisa Grigorieva, Thierry Sturel, Cédric Georges, Brahim Nabi, Florin Duminica
  • Patent number: 11674209
    Abstract: A hot-dip coated steel substrate coated with a layer of Sn directly topped by a zinc or an aluminum based coating is provided, the steel substrate having the following chemical composition in weight percent: 0.10?C?0.4%, 1.2?Mn?6.0%, 0.3?Si?2.5%, Al?2.0%, and on a purely optional basis, one or more elements such as P<0.1%,Nb?0.5%, B?0.005%, Cr?1.0%, Mo?0.50%, Ni?1.0%, Ti?0.5%, the remainder of the composition making up of iron and inevitable impurities resulting from the elaboration, the steel substrate further having between 0.0001 and 0.01% by weight of Sn in the region extending from the steel substrate surface up to 10 ?m.
    Type: Grant
    Filed: October 22, 2018
    Date of Patent: June 13, 2023
    Assignee: ArcelorMittal
    Inventors: Michel Bordignon, Jonas Staudte
  • Patent number: 10927459
    Abstract: An atomic layer deposition (ALD) method can include pulsing a first reactant vapor into a reactor assembly. The first reactant vapor is supplied to a first reactant gas line. An inactive gas is supplied to a first inactive gas line at a first flow rate. The first reactant vapor and the inactive gas are fed to the reactor assembly by way of a first feed line. The reactor assembly is purged by supplying the inactive gas to the first inactive gas line at a second flow rate higher than the first flow rate. A first portion of the inactive gas can be fed back along a diffusion barrier portion of the first reactant gas line to provide an inert gas valve (IGV) upstream of the first inactive gas line. A second portion of the inactive gas can be fed to the reactor assembly by way of the first feed line.
    Type: Grant
    Filed: October 16, 2017
    Date of Patent: February 23, 2021
    Assignee: ASM IP HOLDING B.V.
    Inventor: Eric Jen Cheng Liu
  • Patent number: 10570474
    Abstract: A method for manufacturing a high-strength galvanized steel sheet. The method includes a first heating step of holding the steel sheet in a temperature range of 750° C. to 880° C. for 20 s to 600 s in an atmosphere having an H2 concentration of 0.05% to 25.0% by volume and a dew point of ?45° C. to ?10° C., a cooling step, a rolling step of rolling the steel sheet with a rolling reduction of 0.3% to 2.0%, a pickling step of pickling the steel sheet with a pickling weight loss of 0.02 gram/m2 to 5 gram/m2 in terms of Fe, a second heating step of holding the steel sheet in a temperature range of 720° C. to 860° C. for 20 sec. to 300 sec. in an atmosphere having an H2 concentration of 0.05% to 25.0% by volume and a dew point of ?10° C. or lower, and a galvanizing step.
    Type: Grant
    Filed: June 15, 2015
    Date of Patent: February 25, 2020
    Assignee: JFE STEEL CORPORATION
    Inventors: Mai Aoyama, Yoshitsugu Suzuki, Hideyuki Kimura
  • Publication number: 20150020992
    Abstract: A non-scaling heat-treatable steel with particular suitability for producing hardened or die-hardened components is disclosed, characterized by the following chemical composition in % by weight: C 0.04-0.50; Mn 0.5-6.0; Al 0.5-3.0; Si 0.05-3.0; Cr 0.05-3.0; Ni less than 3.0; Cu less than 3.0; Ti 0.010-?0.050; B 0.0015-?0.0040; P less than 0.10; S less than 0.05; N less than 0.020; remainder iron and unavoidable impurities. Further disclosed is a method for producing a non-scaling hardened component from the steel and a method for producing a hot strip from a steel.
    Type: Application
    Filed: March 19, 2013
    Publication date: January 22, 2015
    Inventors: Joachim Schöttler, Friedrich Luther, Stefan Mütze
  • Patent number: 8911574
    Abstract: A method for manufacturing high-Si cold rolled steel sheets includes heating a cold rolled steel sheet with a direct flame burner (A) having an air ratio of not more than 0.89 when the temperature of the cold rolled steel sheet that is being increased is in the temperature range of not less than 300° C. and less than Ta° C., subsequently heating the cold rolled steel sheet with a direct flame burner (B) having an air ratio of not less than 0.95 when the temperature of the cold rolled steel sheet is in the temperature range of not less than Ta° C. and less than Tb° C., and subsequently soak-annealing the cold rolled steel sheet in a furnace having an atmospheric gas composition which has a dew point of not more than ?25° C. and contains 1 to 10 volume % of H2 and the balance of N2.
    Type: Grant
    Filed: March 28, 2011
    Date of Patent: December 16, 2014
    Assignee: JFE Steel Corporation
    Inventors: Shinji Ootsuka, Junichiro Hirasawa, Hideyuki Takahashi, Naoto Yoshimi, Hideki Nagano
  • Patent number: 8668789
    Abstract: A method for the manufacturing of high strength cold rolled steel sheets includes continuously annealing a cold rolled steel sheet that has a composition containing C: 0.05-0.3% mass, Si: 0.6-3.0% mass, Mn: 1.0-3.0% mass, P: ?0.1% mass, S: ?0.02% mass, Al: 0.01-1% mass, N: ?0.01% mass, and Fe and inevitable impurities: balance, in a manner such that the cold rolled steel sheet is heated in a furnace using an oxidizing burner to a steel sheet temperature of ?700° C., then soak-annealed in a reducing atmosphere furnace at 750-900° C., then cooled so the average cooling rate between 500° C. and 100° C. is ?50° C./s. High-Si cold rolled steel sheets with high strength and good phosphatability while containing Si?0.6% are obtained without controlling conditions so as to increase the dew point in the reducing atmosphere in the soaking furnace or to increase the vapor hydrogen partial pressure ratio.
    Type: Grant
    Filed: July 27, 2010
    Date of Patent: March 11, 2014
    Assignee: JFE Steel Corporation
    Inventors: Junichiro Hirasawa, Naoto Yoshimi, Hiroki Nakamaru, Kohei Hasegawa, Hideyuki Tsurumaru, Keita Yonetsu, Hideyuki Takahashi, Masato Sasaki
  • Patent number: 8491734
    Abstract: A process of production for producing a high strength galvannealed steel sheet by a hot-dip galvanized steel sheet production equipment using an all radiant tube type annealing furnace and a production equipment for the same are provided, comprising continuously hot-dip galvanizing a high strength steel sheet having a content of Si of 0.4 to 2.0 wt % during which making the atmosphere of the reducing zone an atmosphere containing H2 to 1 to 60 wt % and comprised of the balance of N2, H2O, O2, CO2, CO, and unavoidable impurities, controlling the log (PCO2/PH2) of the carbon dioxide partial pressure and hydrogen partial pressure in the atmosphere to log (PCO2/PH2)??0.5 and the log (PH2O/PH2) of the water partial pressure and hydrogen partial pressure to log (PH2O/PH2)??0.5, and controlling the log (PT/PH2) of the total partial pressure PT of the carbon dioxide partial pressure PCO2 and water partial pressure PH2O and the hydrogen partial pressure to ?3?log (PT/PH2)??0.5.
    Type: Grant
    Filed: August 19, 2004
    Date of Patent: July 23, 2013
    Assignees: Nippon Steel & Sumitomo Metal Corporation, Usinor
    Inventors: Kazuhiko Honda, Koki Tanaka
  • Patent number: 8192566
    Abstract: A continuous annealing and pickling process of flat cold-rolled products, such as stainless steel strips, to obtain a high surface quality product at high production rates and with a low environmental impact. It comprises the following steps: heating, up to a temperature comprised in the range 650-1050° C., in an atmosphere with an oxygen content comprised in the range from 0.5 to 12%; heating for a time comprised from 10 to 200 sec up to a temperature comprised in the range from 650 to 1200° C. in presence of oxidizing agents and/or inert agents; cooling down to temperatures comprised in the range from 650° C. to ambient temperature in presence of oxidizing agents and/or inert agents; thermochemical or electrolytic descaling and finally possible pickling and/or passivation, by means of the use of pickling baths consisting of mineral acid solutions.
    Type: Grant
    Filed: November 14, 2007
    Date of Patent: June 5, 2012
    Assignees: Danieli & C. Officine Meccaniche S.p.A., Centro Sviluppo Materiali S.p.A.
    Inventors: Alessandro Dulcetti, Milorad Pavlicevic, Nicoletta Zacchetti, Alessandra Primavera, Stefano Luperi, Luca Lattanzi, Simone Guanin
  • Publication number: 20110139321
    Abstract: Disclosed are an austenitic stainless steel, and a hydrogenation method thereof, in which occurrence of fatigue cracks and growth of fatigue cracks are suppressed by charging the austenitic stainless steel with hydrogen. In particular, focusing on the amount of diffusible hydrogen and non-diffusible hydrogen, which cause hydrogen embrittlement in austenitic stainless steel, the fatigue strength characteristics of austenitic stainless steel are improved by bringing the amount of diffusible hydrogen and non-diffusible hydrogen contained in the austenitic stainless steel to 0.0030 wt % (30 wt ppm) or higher. The austenitic stainless steel is subjected to a thermal treatment at a heating temperature of 200 to 500° C. for up to 460 hours in a hydrogen environment. The hydrogen (H) contained in the austenitic stainless steel is brought thereby to 0.0030 wt % (30 wt ppm) or higher.
    Type: Application
    Filed: July 17, 2009
    Publication date: June 16, 2011
    Applicant: Nat'l Institute of Advanced Industrial Science and Technology
    Inventors: Yukitaka Murakami, Yoji Mine, Toshihiko Kanezaki
  • Patent number: 7887746
    Abstract: An apparatus for thermally treating and coloring a plurality of curved suture needles. The apparatus includes a conveyer for transferring the plurality of curved suture needles from a source of curved suture needles to a receiver, a housing positioned adjacent the conveyer, the housing having a first end, a second end, and an opening running from the first end to the second end, the opening aligned with the conveyer to enable the plurality of curved suture needles to pass therethrough, a heat source located within the housing for heating the plurality of curved suture needles as the plurality of curved suture needles are transferred by the conveyer from the first end of the housing to the second end of the housing and a system for providing a gas mixture containing a fractional concentration of oxygen to oxidize and colorize the surfaces of the plurality of curved suture needles as the plurality of suture needles pass through the housing.
    Type: Grant
    Filed: December 13, 2007
    Date of Patent: February 15, 2011
    Assignee: Ethicon, Inc.
    Inventors: Frank Richard Cichocki, Jr., David Demarest, Gregory Hollin, Eugene D. Reynolds
  • Patent number: 7875235
    Abstract: A method is described for batchwise heat treatment of goods to be annealed which are heated in a heating chamber after scavenging air with a scavenging gas under protective gas to a predetermined treatment temperature, with the protective gas being conveyed through the heating chamber depending on the occurrence of impurities in different quantities. In order to enable the economic use of protective gas, it is proposed that the protective gas which is withdrawn from the heating chamber after the main occurrence of impurities and which is loaded with a residual quantity of impurities is conveyed, optionally after intermediate storage, into the heating chamber during the main occurrence of impurities of a subsequent batch before non-loaded protective gas is introduced into the heating chamber.
    Type: Grant
    Filed: May 11, 2006
    Date of Patent: January 25, 2011
    Assignee: Ebner Industrieofenbau Gesellschaft m.b.H.
    Inventors: Peter Ebner, Heribert Lochner
  • Patent number: 7842142
    Abstract: High-strength parts and a method for producing them can be provided, where such parts exhibit hydrogen embrittlement resistance and strength after high-temperature forming. For example, the atmosphere in a heating furnace can contain less than about 10% hydrogen and/or have a dew point of about 30° C. or less. The amount of hydrogen penetrating a steel sheet during heating can thereby be reduced. After forming, quench hardening in a die assembly and post-working can be performed. Post-working can include shearing followed by re-shearing or compression forming; punching with a cutting blade having a continuously reduced base width; punching with a tool having a curved blade and a protrusion at the tip of the cutting blade, where the curved blade may include a shoulder portion of given radius and/or angle; fusion cutting; etc. Tensile residual stresses after punching can be reduced and resistance to hydrogen embrittlement can be improved.
    Type: Grant
    Filed: September 15, 2005
    Date of Patent: November 30, 2010
    Assignee: Nippon Steel Corporation
    Inventors: Kazuhisa Kusumi, Hironori Sato, Masayuki Abe, Nobuhiro Fujita, Noriyuki Suzuki, Kunio Hayashi, Shinya Nakajima, Jun Maki, Masahiro Oogami, Toshiyuki Kanda, Manabu Takahashi, Yuzo Takahashi
  • Publication number: 20100065167
    Abstract: A continuous annealing and pickling process of flat cold-rolled products, such as stainless steel strips, to obtain a high surface quality product at high production rates and with a low environmental impact. It comprises the following steps: heating, up to a temperature comprised in the range 650-1050° C., in an atmosphere with an oxygen content comprised in the range from 0.5 to 12%; heating for a time comprised from 10 to 200 sec up to a temperature comprised in the range from 650 to 1200° C. in presence of oxidizing agents and/or inert agents; cooling down to temperatures comprised in the range from 650° C. to ambient tempera in presence of oxidizing agents and/or inert agents; thermochemical or electrolytic descaling and finally possible pickling and/or passivation, by means of the use of pickling baths consisting of mineral acid solutions.
    Type: Application
    Filed: November 14, 2007
    Publication date: March 18, 2010
    Inventors: Alessandro Dulcetti, Milorad Pavlicevic, Nicoletta Zacchetti, Alessandra Primavera, Stefano Luperi, Luca Lattanzi, Simone Guanin
  • Publication number: 20100043926
    Abstract: A method for preventing carbon steel from intergranular cracking utilizing a reducing gas instead of nitrogen gas for a heat treatment of feeder pipes for a pressurized heavy water reactor (PHWR) nuclear power plant. This heat treatment protects carbon from oxidation to prevent the formation of decarburized layers so that the feeder pipes can be prevented from intergranular cracking. In addition, intergranular segregation of impurities is inhibited and intergranular strength of the carbon steel is enhanced. Therefore, no intergranular cracking occurs despite the concentration of stress.
    Type: Application
    Filed: October 28, 2008
    Publication date: February 25, 2010
    Inventors: Nam Hoe HEO, Hong Deok Kim, Ki Tae Kim, Jung Kuk Lee, Yong Chan Jung
  • Patent number: 7384489
    Abstract: A method for heat treating metallic strips inside a heat treatment chamber at a pressure greater than atmospheric pressure including passing the strips through at least one heating zone of the chamber and moving the strip through at least one cooling zone of the chamber. A first protective gas atmosphere containing nitrogen and hydrogen and/or helium is established in all but at least one cooling zone. The at least one cooling zone has a second protective atmosphere containing nitrogen and a second amount of hydrogen, the second amount of hydrogen is greater than the first amount. Nitrogen is introduced into the chamber, and a protective gas containing a third hydrogen content greater than the second hydrogen content is injected into the cooling zone, producing a gas exchange between one zone of the chamber having the first protective atmosphere and the cooling zone, and controlling the flow of introduction and injection.
    Type: Grant
    Filed: September 11, 2003
    Date of Patent: June 10, 2008
    Assignee: Drever International S.A.
    Inventors: Jean-Marc Raick, Jean-Pierre Crutzen, Edgard Dosogne, Michel Renard
  • Patent number: 7056399
    Abstract: The present invention provides a process to treat steels, preferably carbon steel to reduce the tendency of the steel to form coke when in contact with hydrocarbons at elevated temperatures. The steel may be first reduced then treated with a mixture of compounds which further modify the reduced surface and finally the treated steel surface is cured. The treated steel has a reduced propensity to form coke when in contact with hydrocarbons particularly at higher temperatures.
    Type: Grant
    Filed: April 29, 2003
    Date of Patent: June 6, 2006
    Assignee: NOVA Chemicals (International) S.A.
    Inventors: Haiyong Cai, Michael C. Oballa, Andrzej Krzywicki, Leslie Wilfred Benum
  • Patent number: 6780257
    Abstract: A base plate of a stainless-steel body material formed by pressing is polished and cleared of burrs by means of an abrasive material that consists mainly of Fe2O3 in a polishing process. The polished base plate is heated to a heat treatment temperature for solid solution in a reducing atmosphere in a heat treatment process. In this heat treatment process, an oxide in the constituents of minute fragments of the abrasive material in the surface of the body material of the base plate is reduced to leave iron, which is dispersed into the body material.
    Type: Grant
    Filed: January 17, 2002
    Date of Patent: August 24, 2004
    Assignees: IBM Japan Ltd., NHK Spring Co., Ltd.
    Inventors: Tsuyoshi Nagata, Hiroyasu Tsuchida, Yoshio Uematsu, Kiyoshi Satoh, Kosuke Tamaru
  • Patent number: 6527884
    Abstract: An apparatus for selectively implementing a depressurized or an atmospheric hydrogen annealing process comprises a reaction chamber, a hydrogen gas introduction line for feeding hydrogen gas into the reaction chamber and an atmospheric exhaust line and a depressurized exhaust line, which are connected to the reaction chamber. By selectively switching the atmospheric exhaust line and the depressurized exhaust line, the depressurized hydrogen annealing process and the atmospheric annealing process are selectively implemented. A device for performing deoxidization process or a device for removing impurities may be further included.
    Type: Grant
    Filed: November 7, 2000
    Date of Patent: March 4, 2003
    Assignee: Hitachi Kokusai Electric, Inc.
    Inventors: Yasunori Takakuwa, Kouji Tometsuka
  • Patent number: 6458217
    Abstract: Systems useful for superadiabatic combustion generation of a reducing atmosphere for metal heat treatment include a superadiabatic reactor which supplies a reducing atmosphere to a metal heat treatment apparatus. In one aspect, the reactor includes a porous medium and a start-up heater in the flow path of the gas that is to be heated. In another aspect, the gas is passed through a porous medium in alternating, opposite directions by the control of valves which lead the gas to and from the medium. In yet another aspect, a gas inflow pipe leads into an insulated porous bed from which the gas flows in a counter flow manner around the inflow pipe.
    Type: Grant
    Filed: February 29, 2000
    Date of Patent: October 1, 2002
    Assignee: American Air Liquide, Inc.
    Inventor: Yao-En Li
  • Patent number: 6358337
    Abstract: Improved process for the annealing of drawn carbon steel rolls and coils of rolled carbon steel sheet. This process is characterized in that in the stage of roll heating the heating is stopped before reaching the temperature at which the reaction between carbon and H2O in the vapour phase starts. The core of the steel roll is then allowed to heat up progressively until its temperature reaches that of the outer part of the roll. With progressive removal of moisture from the core of the steel roll, heating is applied progressively until a minimum moisture level guaranteeing a sufficiently low partial pressure to avoid the reaction between the carbon in the steel and water vapour is reached. Heating is then continued up to the desired annealing temperature.
    Type: Grant
    Filed: May 12, 2000
    Date of Patent: March 19, 2002
    Assignee: L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Luis Vidal Esteban Sanz, Jorge Aixa Barcelo
  • Patent number: 6092389
    Abstract: In an apparatus that rapidly cools heat treated metal strips with a recirculating nitrogen-hydrogen cooling gas mixture having a hydrogen content which ranges between 15%-50%, and a recirculation circuit for the gas mixture having a fan for creating a flow though recirculation ducts connected, through expandable compensator corrugations, upstream to at least one gas/water exchanger, a safety system operates with the exchanger. The safety system includes a housing having a main flow area upstream of the exchanger and into which recirculating cooling gas flows. A first register is interposed across the main flow area for selectively switching between open and closed states thereby passing or blocking flow through a major portion of the main flow area. At least one bypass flow area is defined within the housing and located adjacent the main flow area.
    Type: Grant
    Filed: October 14, 1998
    Date of Patent: July 25, 2000
    Assignee: Stein Heurtey
    Inventor: Gerard Jodet
  • Patent number: 5882445
    Abstract: A method for producing metallic semifinished products such as strip or wire rom metallic work materials which have a high melting point and are difficult to shape, comprising the steps of a) first, alloying at least one element for lowering the melting point with a material that has a high melting point and is difficult to shape; b) then, producing the semifinished product from the alloy with the reduced melting point in the form of strip or wire directly from the melt by quick solidification; and c) finally extracting the elements alloyed with the material in method step a) from the semifinished product by heat treatment in a reactive atmosphere.
    Type: Grant
    Filed: December 18, 1996
    Date of Patent: March 16, 1999
    Assignee: Institut fuer Festkoerper-und Werkstofforschung Dresden e.V.
    Inventor: Stefan Roth
  • Patent number: 5798007
    Abstract: Process for the continuous heat treatment of a metal strip, the latter travelling through a furnace, which is thermally insulated, and in a protective atmosphere; the said furnace consisting of at least one section, for heating, for temperature hold and for cooling; the said strip being guide by a plurality of rollers arranged especially in the lower part and in the upper part of the said sections, so as to form a plurality of runs, wherein the strip passes through at least one partial or total isolating device positioned within at least one section or between two sections, so as to ensure different heat transfer properties on the strip compared with at least one other adjacent section having a different atmosphere, by adjusting the composition of the atmosphere consisting of a gas mixture whose hydrogen or helium content exceeds 5% and more particularly 15%, in order to allow differentiation of the thermomechanical properties of the atmosphere.
    Type: Grant
    Filed: March 11, 1997
    Date of Patent: August 25, 1998
    Assignee: Stein Heurtey
    Inventors: Michel Boyer, Jean-Jacques Nozieres
  • Patent number: 5785773
    Abstract: When cold strip is annealed, diffusion welds, so-called stickers, frequently form on the strip surface. In order to avoid these, the cold strip, above 600.degree. C. (holding time) is coated by oxidation with a thin surface film which prevents the sticking together. Below 600.degree. C., during the cooling phase, this surface film is removed again by reduction. In the case of a protective gas comprising a hydrogen content greater than 5%, remainder nitrogen, carbon dioxide is preferably added as oxidizing agent. The process is controlled via a defined oxygen partial pressure. The reduction is performed via the hydrogen.
    Type: Grant
    Filed: August 20, 1996
    Date of Patent: July 28, 1998
    Assignee: Messer Griesheim-GmbH
    Inventor: Peter Zylla
  • Patent number: 5785774
    Abstract: An endogenerator is provided in which CO and H.sub.2 are generated as primary products of hydrocarbon oxidation. Noble metal catalysts such as platinum (Pt) and particularly rhodium (Rh), are loaded on a porous ceramic support, of example, an alumina carrier. In the endogenerator reactor little or no CO and H.sub.2 are produced by the slow and energy-intensive reforming reactions and this allows for a compact reactor which operates autothermally without auxiliary heating means, and with high space velocities wherein space velocity is defined as the number of standard cubic feet per hour of output gas per cubic foot of the catalyst carrier. Preferred hydrocarbons are methane or propane, preferred oxidants are nitrogen/oxygen mixtures with from 5% oxygen up to 100% oxygen. The endogenerator of the present invention provides a process and apparatus that generates the required reducing gases CO and H.sub.2 for heat treating applications which require leaner atmospheres and lower carbon potentials.
    Type: Grant
    Filed: April 3, 1997
    Date of Patent: July 28, 1998
    Assignee: Praxair Technology, Inc.
    Inventors: Jaak Stefaan Van Den Sype, Alan Russell Barlow
  • Patent number: 5779826
    Abstract: The present invention is directed to a method for forming a heat treating atmosphere in which a nitrogen rich gas containing small amounts of oxygen is preheated. An oxygen-reactive gas, such as a hydrocarbon gas, is combined with the nitrogen rich gas and the mixture is reacted outside of the furnace at temperatures above which substantial sooting does not occur. The resulting heat treating atmosphere is then forwarded to the furnace for conducting the heat treating process.
    Type: Grant
    Filed: September 29, 1997
    Date of Patent: July 14, 1998
    Assignee: The BOC Group, Inc.
    Inventors: Harbhajan S. Nayar, John J. Dwyer, Jr., Edward Chang
  • Patent number: 5772428
    Abstract: A closed-loop control system controls introduction of either water or hydrogen into a furnace region where a part is subjected to an elevated temperature to accomplish a heat treatment process. The heat treatment process causes the part to participate in reduction and/or oxidation reactions which remain in balance at the elevated temperature so long as a hydrogen/water ratio set point is maintained. The system includes an oxygen probe in communication with the furnace region for providing (i) an oxygen output indicative of sensed oxygen concentration within furnace region, and (ii) a temperature output indicative of temperature therein. A controller determines from the oxygen output and temperature output, a measured ratio of hydrogen to water within the furnace region and compares the measured ratio with the hydrogen/water ratio set point, and provides a correction signal output in accordance with a determined difference between the measured ratio and the ratio set point.
    Type: Grant
    Filed: February 9, 1996
    Date of Patent: June 30, 1998
    Assignee: Praxair Technology, Inc.
    Inventors: Jaak Stefaan Van Den Sype, Richard Bruce Vankempema
  • Patent number: 5645655
    Abstract: A process to anneal a steel strip in an annealing furnace in an inert-gas atmosphere containing hydrogen, with reduced formation of carbon black and encompassing the phases of heating, retention and cooling, wherein on the surface of the steel strip are impurities containing carbon components, and wherein during the annealing, there is a reaction between the H.sub.2 and the carbon components of the impurities on the surface of the steel strip, whereby said reaction changes the composition of the inert gas atmosphere in the annealing furnace from an inert gas containing H.sub.2 into a gas mixture containing H.sub.2 and CH.sub.4, which forms an H.sub.2 --CH.sub.4 system, and wherein the annealing furnace is flushed during the phase of retention, the phase of cooling, or during both the phases of retention and cooling, as a function of at least one of the thermodynamic limit values of the H.sub.2 --C.sub.4 system.
    Type: Grant
    Filed: June 8, 1995
    Date of Patent: July 8, 1997
    Assignee: Messer Greiesheim GmbH
    Inventors: Gerhard Gross, Peter Zylla
  • Patent number: 5614039
    Abstract: Method for heat treating a metal in which argon gas is selectively injected into the cooling zone of a heat treating apparatus when the temperature therein is above the level at which significant nitriding will occur.
    Type: Grant
    Filed: September 29, 1995
    Date of Patent: March 25, 1997
    Assignee: The BOC Group, Inc.
    Inventors: Harbhajan S. Nayar, John J. Dwyer, Jr., Neeraj Saxena
  • Patent number: 5587027
    Abstract: A method for manufacturing a canning steel sheet with non-aging property and superior workability uses, as a starting material, an ultra-low-carbon steel slab composed of from 0.0015% to 0.0100% by weight C, up to 0.20% by weight Si, from 0.10% to 1.20% by weight Mn, from 0.02% to 0.10% by weight Al, from 0.005% to 0.040% by weight P, up to 0.015% by weight S, up to 0.005% by weight N, and balance iron and unavoidable impurities. The manufacturing method includes hot rolling the steel, cold rolling the steel at a reduction ratio not less than 70% after pickling, and recrystallization annealing the steel by using a continuous annealing furnace in an atmosphere having a hydrogen content not less than 3% and a dew point not lower than -20.degree. C. at a temperature not lower than 730.degree. C. so that the content of remained C in the steel is kept less than 0.0015% by weight. At least one element selected from Nb, Ti and B may be added in predetermined amounts to the above composition.
    Type: Grant
    Filed: February 15, 1995
    Date of Patent: December 24, 1996
    Assignee: Kawasaki Steel Corporation
    Inventors: Akio Tosaka, Chikako Fujinaga, Toshiyuki Kato, Kaku Sato, Hideo Kuguminato
  • Patent number: 5569339
    Abstract: The present invention relates to a method for annealing metal parts, in particular sheets, in an annealing chamber of an industrial furnace under a protective-gas atmosphere, wherein the annealing comprises a heating phase, a soaking phase and a cooling phase. The annealing chamber is purged during the heating phase with hydrogen or gas rich in hydrogen until the protective gas predominantly contains hydrogen. According to the present invention a purging with an inert gas is performed towards the end of the heating phase to reduce the percentage of hydrogen in the protective gas so that the formation of carbon-containing breakdown products is largely avoided. This prevents the formation of annealing edges during the soaking phase. Towards the end of the soaking phase, a purging with hydrogen or gas rich in hydrogen is performed until the protective gas predominantly contains hydrogen and carbon-containing deposits can be removed.
    Type: Grant
    Filed: August 9, 1995
    Date of Patent: October 29, 1996
    Assignee: LOI Thermprocess GmbH
    Inventor: Walter Scheuermann
  • Patent number: 5441581
    Abstract: An endogenerator is provided in which CO and H.sub.2 are generated as primary products of hydrocarbon oxidation. Noble metal catalysts such as platinum (Pt) and particularly rhodium (Rh), are loaded on a porous ceramic support, of example, an alumina carrier. In the endogenerator reactor little or no CO and H.sub.2 are produced by the slow and energy-intensive reforming reactions and this allows for a compact reactor which operates autothermally without auxiliary heating means, and with high space velocities wherein space velocity is defined as the number of standard cubic feet per hour of output gas per cubic foot of the catalyst carrier. Preferred hydrocarbons are methane or propane, preferred oxidants are nitrogen/oxygen mixtures with from 5% oxygen up to 100% oxygen. The endogenerator of the present invention provides a process and apparatus that generates the required reducing gases CO and H.sub.2 for heat treating applications which require leaner atmospheres and lower carbon potentials.
    Type: Grant
    Filed: June 6, 1994
    Date of Patent: August 15, 1995
    Assignee: Praxair Technology, Inc.
    Inventors: Jaak S. Van den Sype, Alan R. Barlow
  • Patent number: 5261976
    Abstract: A control arrangement is disclosed for a conventional, atmosphere heat treating furnace which is operated at high temperature and fitted with a vacuum pump to draw rough or soft vacuum levels when heating the work to heat treat temperatures. The control arrangement utilizes a hydrogen--inert gas furnace atmosphere continuously metered into the furnace to produce a reducing gas mixture to prevent oxidation of the work. If oxidation conditions are sensed, the mass flow is automatically increased while vacuum levels are maintained constant. A unique oxygen probe mounting arrangement is disclosed which enables a conventional oxygen probe to give fairly accurate and consistent readings for fast, automatic process control.
    Type: Grant
    Filed: December 31, 1991
    Date of Patent: November 16, 1993
    Assignee: Gas Research Institute
    Inventor: Thomas J. Schultz
  • Patent number: 5137586
    Abstract: An improved method of heat treating a continuous strip of metallic material of indeterminate length in a continuous annealing furnace. The furnace includes a heating section having a plurality of gas jet heaters and a cooling section having a plurality of gas jet coolers. The continuous strip is heated and cooled in the heating and cooling sections within predetermined selected temperature ranges for the strip, by convection and solely with mixtures of hydrogen and nitrogen gases impinged against both sides of the strip through the gas jet heaters and the gas jet coolers. The temperatures of the strips in the heating and cooling section are monitored. Temperatures are controlled by varying the ratios of the mixtures of the heating and cooling gases which achieves and maintains the predetermined selected temperature ranges for the strip in the heating and cooling chambers despite changes in operating conditions.
    Type: Grant
    Filed: January 2, 1991
    Date of Patent: August 11, 1992
    Inventor: James H. Klink