Nine Percent Or More Chromium(cr) (e.g., Stainless Steel, Etc.) Patents (Class 148/592)
  • Patent number: 10597743
    Abstract: A process for producing a high-grade steel tube includes the steps of: providing a tubular blank of an austenitic high-grade steel, wherein the high-grade steel comprises in weight % no more than 0.02% carbon, no more than 1.0% manganese, no more than 0.03% phosphor, no more than 0.015% sulfur, no more than 0.8% silicon, no more than 17.5% t to 18.5% nickel, no more than 19.5% to 20.5% chromium, no more than 6.0% to 6.5% molybdenum, no more than 0.18% to 0.25% nitrogen, no more than 0.5% to 1.0% copper, and a remainder of iron and unavoidable impurities; and cold-forming the blank into a tube.
    Type: Grant
    Filed: July 16, 2015
    Date of Patent: March 24, 2020
    Assignee: Sandvik Materials Technology Deutschland GmbH
    Inventors: Jonas Guhrs, Christofer Hedvall, Thomas Frobose, Udo Rauffmann
  • Patent number: 10351940
    Abstract: A method of manufacturing a component from a nickel-based superalloy comprises the steps of: providing a vacuum induction casting furnace; positioning a component mould onto a chill plate within the furnace; casting a component blank; peening the surface of the component blank; applying a surface modification technique to the surface of the component blank; solution heat treating the component blank at or above the ??-solvus temperature for the superalloy; and precipitation heat treating the component blank.
    Type: Grant
    Filed: August 24, 2017
    Date of Patent: July 16, 2019
    Assignee: ROLLS-ROYCE plc
    Inventor: John H Boswell
  • Patent number: 10329648
    Abstract: A method for manufacturing a superior 13Cr thickened drillrod comprises the following steps: firstly, thickening the ends of a steel tube with a composition so as to obtain a drillrod with thickened ends, the composition in percentage by weight being: C: 0.01-0.05%, Si?0.5%, Mn: 0.2-1.0%, Cr: 12-14%, Mo: 1-3%, Ni: 4-6%, and a balance of Fe and inevitable impurities; after heating the tube as a whole to 950-1000° C., air cooling same and tempering same at 600-650° C.; and machining the two thickened ends respectively into an externally threaded drillrod coupler and an internally threaded drillrod coupler; wherein the tube end thickening is an external thickening, including three rounds of heating and three rounds of thickening, with at least one pass of deformation for each round, and the heating temperature being 1150-1200° C.
    Type: Grant
    Filed: November 12, 2013
    Date of Patent: June 25, 2019
    Assignee: Baoshan Iron & Steel Co., Ltd.
    Inventors: Peng Zhao, Yanpeng Song, Jianwei Zhang, Minghua Wang, Chunxia Zhang
  • Patent number: 10316380
    Abstract: A thermal mechanical treatment method includes consolidating a powder by a severe plastic deformation process and ageing the consolidated powder at low temperature. The method may include cryomilling the powder before consolidating the powder by a severe plastic deformation process; hot isostatic pressing the consolidated powder into a dense powder before aging the consolidated powder; hot extruding the dense powder into a stock shape before aging the consolidated powder; hot-working the stock shape on a gyrating forge at a predetermined temperature before aging the consolidated powder; or heating the consolidated powder to a predetermined temperature, and maintaining the consolidated powder at the predetermined temperature for a predetermined time.
    Type: Grant
    Filed: March 31, 2014
    Date of Patent: June 11, 2019
    Assignee: SCHLUMBERGER TECHNOLOG CORPORATION
    Inventors: Indranil Roy, Rashmi Bhavsar
  • Patent number: 10174391
    Abstract: The invention relates to a method for producing martensitic steel that comprises a content of other metals such that the steel can be hardened by an intermetallic compound and carbide precipitation, with an Al content of between 0.4% and 3%, comprising the following steps: (a) heating the entirety of the steel above its austenizing temperature, (b) cooling said steel approximately to ambient temperature, (c) placing said steel in a cryogenic medium. The temperature T1 is substantially lower than the martensitic transformation temperature Mf, and the time t during which said steel is kept in said cryogenic medium at a temperature T1 from the moment when the hottest part of the steel reaches a temperature lower than the martensitic transformation temperature Mf is at least equal to a non-zero time t1, the temperature T1 (in ° C.
    Type: Grant
    Filed: July 2, 2010
    Date of Patent: January 8, 2019
    Assignee: SAFRAN AIRCRAFT ENGINES
    Inventor: Laurent Ferrer
  • Patent number: 9783876
    Abstract: A stainless steel for oil wells which has excellent high-temperature corrosion resistance and can stably obtain a strength of not less than 758 MPa is provided. The stainless steel for oil wells contains, by masse, C: not more than 0.05%, Si: not more than 1.0%, Mn: 0.01 to 1.0%, P: not more than 0.05%, S: less than 0.002%, Cr: 16 to 18%, Mo: 1.8 to 3%, Cu: 1.0 to 3.5%, Ni: 3.0 to 5.5%, Co: 0.01 to 1.0%, Al: 0.001 to 0.1%, O: not more than 0.05%, and N: not more than 0.05%, the balance being Fe and impurities, and satisfies Formulas (1) and (2): Cr+4Ni+3Mo+2Cu?44??(1) Cr+3Ni+4Mo+2Cu/3?46??(2) where each symbol of element in Formulas (1) and (2) is substituted by the content (mass %) of a corresponding element.
    Type: Grant
    Filed: February 27, 2013
    Date of Patent: October 10, 2017
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Shinjiro Nakatsuka, Taro Ohe, Hisashi Amaya, Hideki Takabe, Yohei Otome, Yusaku Tomio, Masanao Seo, Tomohiko Omura, Kunio Kondo
  • Patent number: 9758850
    Abstract: A pipe having chemical composition contains, by mass %, C: 0.05% or less, Si: 0.5% or less, Mn: 0.15% or more and 1.0% or less, Cr: 13.5% or more and 15.4% or less, Ni: 3.5% or more and 6.0% or less, Mo: 1.5% or more and 5.0% or less, Cu: 3.5% or less, W: 2.5% or less, and N: 0.15% or less so that the relationship ?5.9×(7.82+27C?0.91 Si+0.21Mn?0.9Cr+Ni?1.1Mo?0.55W+0.2Cu+11N)?13.0 is satisfied.
    Type: Grant
    Filed: June 19, 2013
    Date of Patent: September 12, 2017
    Assignee: JFE Steel Corporation
    Inventors: Kenichiro Eguchi, Yasuhide Ishiguro, Yukio Miyata, Mitsuo Kimura
  • Patent number: 9303296
    Abstract: A high-strength stainless steel for oil well having corrosion resistance excellent in a high-temperature environment, having excellent SSC resistance at normal temperature, and having better workability than 13% Cr steels has a chemical composition containing, by mass percent, C: at most 0.05%, Si: at most 1.0%, Mn: at most 0.3%, P: at most 0.05%, S: less than 0.002%, Cr: over 16% and at most 18%, Mo: 1.5 to 3.0%, Cu: 1.0 to 3.5%, Ni: 3.5 to 6.5%, Al: 0.001 to 0.1%, N: at most 0.025%, and O: at most 0.01%, the balance being Fe and impurities, a microstructure containing a martensite phase, 10 to 48.5%, by volume ratio, of a ferrite phase and at most 10%, by volume ratio, of a retained austenite phase, yield strength of at least 758 MPa and uniform elongation of at least 10%.
    Type: Grant
    Filed: September 10, 2012
    Date of Patent: April 5, 2016
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Taro Ohe, Hisashi Amaya, Hideki Takabe, Kunio Kondo, Yohei Otome
  • Patent number: 9109268
    Abstract: The chemical composition of a stainless steel in accordance with the present invention consists of C: not more than 0.05%, Si: not more than 0.5%, Mn: 0.01 to 0.5%, P: not more than 0.04%, S: not more than 0.01%, Cr: more than 16.0 and not more than 18.0%, Ni: more than 4.0 and not more than 5.6%, Mo: 1.6 to 4.0%, Cu: 1.5 to 3.0%, Al: 0.001 to 0.10%, and N: not more than 0.050%, the balance being Fe and impurities, and satisfies Formulas (1) and (2). Also, the micro-structure thereof contains a martensitic phase and a ferritic phase having a volume ratio of 10 to 40%, and the ferritic phase distribution ratio is higher than 85%. Cr+Cu+Ni+Mo?25.5??(1) ?8?30(C+N)+0.5Mn+Ni+Cu/2+8.2?1.
    Type: Grant
    Filed: October 19, 2011
    Date of Patent: August 18, 2015
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Hideki Takabe, Kunio Kondo, Hisashi Amaya, Taro Ohe, Yohei Otome
  • Patent number: 8900384
    Abstract: In a method for heat treating a metal tube or pipe for a nuclear power plant, the tube or pipe being accommodated in a batch-type vacuum heat treatment furnace, when the tube or pipe is laid down on and is subjected to heat treatment on a plurality of metal cross beams arranged along a longitudinal direction of the tube or pipe, it is possible to suppress scratches to be formed on the outer surface of the tube or pipe and attributable to heat treatment, and to reduce the discoloration on the outer surface of the tube or pipe by holding the tube or pipe and the metal cross beams in indirect contact with each other by virtue of a heat resistant fabric having a thickness of 0.1 to 1.2 mm interposed in between.
    Type: Grant
    Filed: July 23, 2012
    Date of Patent: December 2, 2014
    Assignee: Nippon Steel & Sumitomo Metal Corporation
    Inventors: Shoji Kinomura, Shinichi Takenaka
  • Patent number: 8876990
    Abstract: Methods to enhance the quality of grain boundary networks are described. The process can result in the production of a metal including a relatively large fraction of special grain boundaries (e.g., a fraction of special grain boundaries of at least about 55%).
    Type: Grant
    Filed: August 20, 2009
    Date of Patent: November 4, 2014
    Assignee: Massachusetts Institute of Technology
    Inventors: Christopher A. Schuh, Koichi Kita
  • Patent number: 8871039
    Abstract: The present invention provides a thick welded steel pipe excellent in low temperature toughness in which contents of Mn and Mo satisfy (Expression 1) below, Pcm obtained by (Expression 2) below is 0.16 to 0.19, and a metal structure of a base material steel plate consists of ferrite being 30 to 95% in an area ratio and a low temperature transformation structure, and in a metal structure of a coarse-grained HAZ, an area ratio of grain boundary ferrite is 1.5% or more, the total area ratio of the grain boundary ferrite and intragranular ferrite is not less than 11% nor more than 90%, an area ratio of MA is 10% or less, and its balance is composed of bainite. 1.2325?(0.85×[Mn]?[Mo])?1.5215??(Expression 1) and Pcm=[C]+[Si]/30+([Mn]+[Cu]+[Cr])/20+[Ni]/60+[Mo]/15+[V]/10??(Expression 2).
    Type: Grant
    Filed: September 13, 2011
    Date of Patent: October 28, 2014
    Assignee: Nippon Steel & Sumitomo Metal Corporation
    Inventors: Yasuhiro Shinohara, Takuya Hara, Naoki Doi, Eiichi Yamashita
  • Patent number: 8858740
    Abstract: In a method for heat treating a metal tube or pipe for a nuclear power plant, the tube or pipe being accommodated in a batch-type vacuum heat treatment furnace, when the tube or pipe is laid down on and is subjected to heat treatment on a plurality of metal cross beams arranged along a longitudinal direction of the tube or pipe, it is possible to suppress scratches to be formed on the outer surface of the tube or pipe and attributable to heat treatment, and to reduce the discoloration on the outer surface of the tube or pipe by holding the tube or pipe and the metal cross beams in indirect contact with each other by virtue of a heat resistant fabric having a thickness of 0.1 to 1.2 mm interposed in between.
    Type: Grant
    Filed: July 23, 2012
    Date of Patent: October 14, 2014
    Assignee: Nippon Steel & Sumitomo Metal Corporation
    Inventors: Shoji Kinomura, Shinichi Takenaka
  • Patent number: 8784581
    Abstract: An Fe—Ni alloy pipe stock containing, by mass %, C?0.04%, Si?0.50%, Mn: 0.01 to 6.0%, P?0.03%, S?0.01%, Cr: 20 to 30%, Ni: 30 to 45%, Mo: 0 to 10%, W: 0 to 20%, with Mo(%)+0.5W(%): more than 1.5% to not more than 10%, Cu: 0.01 to 1.5%, Al?0.01% and N: 0.0005 to 0.20%, and the balance being Fe, with 1440?6000P?100S?2000C?1300, Ni+10(Mo+0.5W)+100N?120, (Ni?35)+10(N?0.1)?2(Cr?25)?5(Mo+0.5W?3)+8?0, can be manufactured into a seamless pipe by use of a Mannesmann piercing and rolling mill because of its excellent inner surface properties. The resulting seamless pipe has excellent mechanical properties and moreover has excellent corrosion resistance in a sour gas environment.
    Type: Grant
    Filed: December 22, 2006
    Date of Patent: July 22, 2014
    Assignee: Nippon Steel & Sumitomo Metal Corporation
    Inventors: Masaaki Igarashi, Kazuhiro Shimoda, Tomio Yamakawa, Hisashi Amaya
  • Patent number: 8613817
    Abstract: The present invention is to provide a method for producing duplex stainless steel seamless pipe in which a duplex stainless steel billet can be inhibited from generating an oxide scale on the surface thereof during heating and the generation of outer surface flaw can also be prevented. The billet is heated in the a heating furnace for 1.5 hours or more and 4.0 hours or less at a heating temperature of 1250° C. or more and 1320° C. or less while regulating the average concentration of sulfur dioxide (SO2) gas in the atmosphere within the furnace to 0.01 volume % or less.
    Type: Grant
    Filed: March 23, 2007
    Date of Patent: December 24, 2013
    Assignee: Nippon Steel & Sumitomo Metal Corporation
    Inventors: Naoya Hirase, Tetsuya Nakanishi, Kazuhiro Shimoda, Hirokazu Okada, Tomio Yamakawa, Yasuyoshi Hidaka
  • Patent number: 8479549
    Abstract: A method of producing a seamless, tubular product includes centrifugally casting a corrosion resistant alloy into a tubular workpiece having an inner diameter and an outer diameter. The method then removes material from the inner diameter of the workpiece and subjects the workpiece to at least about a 25% wall reduction at a temperature below a recrystallization temperature of the workpiece using a metal forming process. The metal forming process includes radial forging, rolling, pilgering, and/or flowforming.
    Type: Grant
    Filed: August 13, 2010
    Date of Patent: July 9, 2013
    Assignee: Dynamic Flowform Corp.
    Inventor: Matthew V. Fonte
  • Patent number: 8366843
    Abstract: A method of manufacturing a 13Cr steel pipe which satisfies a hardness (HRC) of at most 22 with 13Cr grade L80 of American Petroleum Institute (API) standards, which is an indicator of a high strength, high yield ratio, and good corrosion resistance, is provided. A steel billet having a chemical composition comprising, in mass percent, C: 0.15-0.21%, Si: 0.16-1.0%, Mn: 0.35-1.0%, Cr: 10.5-14.0%, P: at most 0.020%, S: at most 0.0050%, Al: 0.025-0.050%, and a remainder of Fe and impurities is subjected to hot working with a finishing temperature of 800-960° C. to form a mother pipe, which is immediately quenched at a cooling rate of at least air cooling and then tempered by heating.
    Type: Grant
    Filed: March 27, 2007
    Date of Patent: February 5, 2013
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventor: Nobuyuki Mori
  • Patent number: 8333851
    Abstract: A method for producing a two-phase stainless steel pipe, which comprises: preparing a two-phase stainless steel material consisting of, by mass %, C: 0.03% or less, Si: 1% or less, Mn: 0.1 to 2%, Cr: 20 to 35%, Ni: 3 to 10%, Mo: 0 to 4%, W: 0.5 to 6%, Cu: 0 to 3% and N: more than 0.175 and up to 0.35%, and the balance being Fe and impurities; forming a material pipe by subjecting to a hot working: and performing a cold drawing, where the cold drawing is characterized in being performed under the conditions that the working ratio Rd, in terms of the reduction of area, in the final cold drawing step is within a range from 5 to 35%, and the following formula (1) is satisfied: Rd(%)?(MYS?55)/17.2?{1.2×Cr+3.0×(Mo+0.5×W)}??(1).
    Type: Grant
    Filed: July 8, 2008
    Date of Patent: December 18, 2012
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventor: Hitoshi Suwabe
  • Patent number: 8293037
    Abstract: A method for producing a duplex stainless steel pipe having a minimum yield strength of 758.3 to 965.2 MPa, comprises first hot working and optionally solution heat treating a duplex stainless steel material pipe having a chemical composition consisting, by mass %, of C: 0.03% or less, Si: 1% or less, Mn: 0.1 to 4%, Cr: 20 to 35%, Ni: 3 to 10%, Mo: 0 to 6%, W: 0 to 6%, Cu: 0 to 3% and N: 0.15 to 0.60%, the balance being Fe and impurities. The pipe is then cold rolled under conditions that the working ratio Rd, in terms of the reduction of area, in the final cold rolling step falls within a range from 10 to 80%, and formula (1) is satisfied: Rd=exp[{In(MYS)?In(14.5×Cr+48.3×Mo+20.7×W+6.9×N)}/0.195]??(1) wherein Rd is a reduction in area %, MYS is the targeted yield strength (MPa), and Cr, Mo, W and N are in mass %.
    Type: Grant
    Filed: July 18, 2011
    Date of Patent: October 23, 2012
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventors: Hitoshi Suwabe, Toshihide Ono
  • Patent number: 8172959
    Abstract: There are provided an austenitic stainless steel having high stress corrosion crack resistance, characterized by containing, in percent by weight, 0.030% or less C, 0.1% or less Si, 2.0% or less Mn, 0.03% or less P, 0.002% or less S, 11 to 26% Ni, 17 to 30% Cr, 3% or less Mo, and 0.01% or less N, the balance substantially being Fe and unavoidable impurities; a manufacturing method for an austenitic stainless steel, characterized in that a billet consisting of the said austenitic stainless steel is subjected to solution heat treatment at a temperature of 1000 to 1150° C.; and a pipe and a in-furnace structure for a nuclear reactor to which the said austenitic stainless steel is applied.
    Type: Grant
    Filed: January 13, 2005
    Date of Patent: May 8, 2012
    Assignees: Mitsubishi Heavy Industries, Ltd., The Tokyo Electric Power Company, Inc.
    Inventors: Yasuhiro Sakaguchi, Toshihiko Iwamura, Hiroshi Kanasaki, Hidehito Mimaki, Masaki Taneike, Shunichi Suzuki, Kenrou Takamori, Suguru Ooki, Naoki Anahara, Naoki Hiranuma, Toshio Yonezawa
  • Patent number: 8168014
    Abstract: The method for manufacturing a martensitic stainless pipe includes heating the steel pipe until the external surface temperature thereof reaches a predetermined temperature not lower than A3 transformation point+20° C. and not higher than 980° C. The heated steel pipe is first water cooled until the external surface temperature thereof reaches a predetermined temperature not lower than 350° C. The water cooled steel pipe is air cooled until the external surface temperature thereof reaches a predetermined temperature not higher than 250° C. The air cooled steel pipe is either water or air cooled until the external surface temperature thereof reaches normal temperature. The cooling rate of the steel pipe in the first cooling step is determined according to the wall thickness of the steel pipe so that the amount of heat recuperation for the external surface temperature of the steel pipe in the second cooling step is not higher than 50° C.
    Type: Grant
    Filed: March 26, 2008
    Date of Patent: May 1, 2012
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventor: Nobuyuki Mori
  • Publication number: 20120031534
    Abstract: A method for producing a high-strength Cr—Ni alloy seamless pipe comprising preparing an alloy billet with a chemical composition consisting, by mass %, of C: 0.05% or less, Si: 1.0% or less, Mn: less than 3.0%, P: 0.005% or less, S: 0.005% or less, Cu: 0.01 to 4.0%, Ni: 25% or more and less than 35%, Cr: 20 to 30%, Mo: 0.01% or more and less than 4.0%, N: 0.10 to 0.30%, Al: 0.03 to 0.30%, O (oxygen): 0.01% or less, REM (rare earth metal): 0.01 to 0.20%, and the balance being Fe and impurities, and satisfying the formula N×P/REM?0.10, wherein P, N and REM represent the contents (mass %) of P, N and REM, respectively. The pipe is hot worked using cross roll piercing, solution heat treated, and cold worked. The pipe is excellent in hot workability, stress corrosion cracking and does not laminate during cross piercing.
    Type: Application
    Filed: September 26, 2011
    Publication date: February 9, 2012
    Applicant: SUMITOMO METAL INDUSTRIES, LTD.
    Inventors: Yohei OTOME, Masaaki Igarashi, Hirokazu Okada, Kunio Kondo, Masayuki Sagara, Kazuhiro Shimoda
  • Patent number: 8075991
    Abstract: A stainless steel material for a fuel cell, used for a fuel cell or a cartridge for the fuel cell, having a magnetic permeability of 1.000 to 2.500, and forming a layer having a value of chromium atomic %/iron atomic % of not less than 3.0 in the most surface thereof, and/or the layer of thickness of not less than 12 nm calculated as SiO2 having an oxygen atomic % of not less than 20%. Even when brought into contact with the content solution exhibiting acidity of the fuel cell, the stainless steel material reliably suppresses the elution of metal ions thereof.
    Type: Grant
    Filed: August 9, 2007
    Date of Patent: December 13, 2011
    Assignee: Toyo Seikan Kaisha, Ltd.
    Inventors: Kouki Kinouchi, Wataru Kurokawa, Shouzou Shintani, Kinuyo Shintani, legal representative, Daisuke Imoda, Kenji Yoshihiro, You Yamamori
  • Patent number: 8038811
    Abstract: A steel pipe is prepared, which contains, by mass, at most 0.009% C, at most 1.0% Mn, at most 1.0% Si, at most 0.04% P, at most 0.005% S, 0.01 to 0.2% Ti, 0.01 to 0.10% V, 0.001 to 0.1% Al, at most 0.1% N, 4.0 to 8.0% Ni, 9.0 to 15.0% Cr, and 1.5 to 7.0% Mo, the balance being Fe and impurities. The prepared steel pipe is bent into a bend pipe. The bend pipe is quenched at a quenching temperature lower than 950° C. The quenched bend pipe is tempered. Accordingly, the bend pipe in accordance with the present invention has excellent SSC resistance.
    Type: Grant
    Filed: September 23, 2009
    Date of Patent: October 18, 2011
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventor: Takahiro Oka
  • Patent number: 8034198
    Abstract: The present invention relates to an austenitic stainless steel tube for boiler, used for superheater or reheater in thermal power plant, giving excellent resistance to high temperature steam oxidation, in particular to an austenitic stainless steel tube containing 16 to 20% Cr by weight, and being cold-worked at the inner surface of the tube. The Cr concentration in the vicinity of the inner surface of the steel tube is 14% by weight or larger, and the hardness at 100 ?m depth from the inner surface of the steel tube is 1.5 times or larger the average hardness of the mother material or is HV 300 or larger.
    Type: Grant
    Filed: August 23, 2006
    Date of Patent: October 11, 2011
    Assignee: NKK Tubes
    Inventors: Yusuke Minami, Hitoshi Iijima, Motohisa Yoshida, Toshihiko Fukui, Tatsuo Ono
  • Patent number: 8021502
    Abstract: A martensitic stainless steel pipe, which comprises specified quantities of C, Si, Mn, P, S, Cr, Ni, Al, N, Cu, Ti, V, Mo, Nb, B and Ca, and the balance being Fe and impurities, has satisfactory toughness at a high strength of 650 MPa or more by yield strength and also excellent hot workability. Therefore, it can be used as a high-strength martensitic stainless steel pipe for carbon dioxide gas corrosion resistant use, to be used in oil and/or gas well environments containing no hydrogen sulfide but carbon dioxide gas. This high-strength martensitic stainless steel pipe is an inexpensive martensitic stainless steel pipe, which does not require an addition of large quantities of expensive elements such as Ni and Mo, and moreover does not require the control of the content of P to a value less than 0.010% by mass.
    Type: Grant
    Filed: December 16, 2008
    Date of Patent: September 20, 2011
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventors: Mutsumi Tanida, Nobuyuki Mori, Keiichi Nakamura
  • Publication number: 20110132501
    Abstract: A martensitic stainless steel seamless tube for oil country tubular goods includes a yield strength of 95 ksi or more and low-temperature toughness in which a fracture transition temperature vTrs in a Charpy impact test is ?40° C. or below, wherein the seamless tube has a composition comprising, by mass %, 0.020% or less C, 10 to 14% Cr, 3% or less Ni, 0.03 to 0.2% Nb, 0.05% or less N, and Fe and unavoidable impurities as a balance, and has a structure where a precipitated Nb quantity is 0.020% or more in terms of Nb.
    Type: Application
    Filed: December 24, 2008
    Publication date: June 9, 2011
    Applicant: JFE STEEL CORPORATION
    Inventors: Kenichiro Eguchi, Yukio Miyata, Mitsuo Kimura
  • Patent number: 7926180
    Abstract: A method for making gas and liquid storage tanks such as automotive fuel tanks includes providing two or more blanks of air hardenable martensitic stainless steel in the annealed condition. The steel blanks have a thickness in the range of 0.5-5.0 mm., and are formed utilizing stamping, forging, pressing, or roller forming techniques or the like into the form of a tank shell components. The shell components are hardened and assembled into a storage tank. The shell components are hardened by application of heat, preferably to between 950° C. and 1100° C. for standard air hardenable martensitic stainless steels. Thereafter, the automotive fuel tank is preferably cooled at a rate greater than 25° C. per minute to achieve a Rockwell C hardness of at least 39. The automotive fuel tank may undergo additional heat treating processes including high temperature or low temperature tempering processes which may incorporate electro-coating.
    Type: Grant
    Filed: October 4, 2006
    Date of Patent: April 19, 2011
    Inventors: Edward J. McCrink, Danny Codd
  • Publication number: 20110024005
    Abstract: A two-phase stainless steel pipe that has not only a corrosion resistance required for oil well pipes but at the same time has a targeted strength is produced, without excessively adding alloying components, by selecting cold drawing conditions. A method for producing a two-phase stainless steel pipe, which comprises, preparing a two-phase stainless steel material having a chemical composition that consists of, by mass %, C: 0.03% or less, Si: 1% or less, Mn: 0.1 to 2%, Cr: 20 to 35%, Ni: 3 to 10%, Mo: 0 to 4%, W: 0 to 6%, Cu: 0 to 3% and N: 0.15 to 0.35%, and the balance being Fe and impurities, forming a material pipe by subjecting to a hot working or further a solid-solution heat treatment, and performing a cold drawing, where the cold drawing is characterized in being performed under the conditions that the working ratio Rd, in terms of the reduction of area, in the final cold drawing step is within a range from 5 to 35%, and the following formula (1) is satisfied: Rd(%)?(MYS?55)/17.2?{1.2×Cr+3.0×(Mo+0.
    Type: Application
    Filed: July 8, 2008
    Publication date: February 3, 2011
    Applicant: SUMITOMO METAL INDUSTRIES, LTD.
    Inventor: Hitoshi Suwabe
  • Patent number: 7862666
    Abstract: A highly corrosion resistant high strength stainless steel pipe for linepipe, having a composition containing about 0.001 to about 0.015% C, about 0.01 to about 0.5% Si, about 0.1 to about 1.8% Mn, about 0.03% or less P, about 0.005% or less S, about 15 to about 18% Cr, about 0.5% or more and less than about 5.5% Ni, about 0.5 to about 3.5% Mo, about 0.02 to about 0.2% V, about 0.001 to about 0.015% N, and about 0.006% or less O, by mass, so as to satisfy (Cr+0.65 Ni +0.6Mo+0.55Cu?20C?18.5), (Cr+Mo+0.3Si?43.5C?0.4Mn?Ni?0.3Cu?9 N?11.5) and (C+N?0.025). Preferably quenching and tempering treatment is applied to the pipe. The composition may further contain about 0.002 to about 0.05% Al, and may further contain one or more of Nb, Ti, Zr, B, and W, and/or Cu and Ca. The microstructure preferably contains martensite, ferrite, and residual ?.
    Type: Grant
    Filed: October 22, 2004
    Date of Patent: January 4, 2011
    Assignee: JFE Steel Corporation
    Inventors: Mitsuo Kimura, Takanori Tamari, Yoshio Yamazaki, Ryosuke Mochizuki
  • Publication number: 20100193087
    Abstract: A seamless steel pipe for oil country tubular goods which simultaneously has a high strength of a 110 ksi grade of yield strength and a superior low temperature toughness and a method for manufacturing the same are provided. A quenching treatment is performed on a stainless steel seamless pipe having a composition which contains on a mass percent basis, less than 0.010% of C, 1.0% or less of Si, 0.1% to 2.0% of Mn, 0.020% or less of P, 0.010% or less of S, 0.10% or less of Al, 10% to 14% of Cr, 0.1% to 4.0% of Ni, 0.05% or less of N, and the balance being Fe and inevitable impurities in which after heating is performed to a heating temperature for quenching equivalent to or more than the Ac3 transformation point, cooling is performed to a temperature range of 100° C. or less at a cooling rate equivalent to or more than that of air cooling; and following the quenching treatment, a tempering treatment is performed in which heating is performed to a tempering temperature in the range of more than 450° C.
    Type: Application
    Filed: October 10, 2007
    Publication date: August 5, 2010
    Applicant: JFE STEEL CORPORATION
    Inventors: Yukio Miyata, Mitsuo Kimura, Masahito Tanaka, Ken Shimamoto
  • Patent number: 7686897
    Abstract: The present invention provides a martensitic stainless steel seamless pipe and a method of making, wherein the pipe has minimal inner surface defects and prevents delayed fracture generation in the impact-worked portions. The pipe comprises C: 0.15 to 0.22%, Si: 0.1 to 1.0%, Mn: 0.10 to 1.00%, Cr: 12.00 to 14.00%, P: 0.020% or less, S: 0.010% or less, N: 0.05% or less, O(Oxygen): 0.0060% or less, at least one alloying element selected from V, Nb and Ti of 0.005 to 0.200% and B of 0.0005 to 0.0100%, and the balance Fe and impurities, wherein either the following inequalities (1), (2), (4) and (5) or the following inequalities (1), (3), (4) and (5) are satisfied: C*+10N*?0.45,??(1) H1??0.003(C*+10N*)+0.0016,??(2) H2??0.0018(C*+10N*)+0.00096,??(3) Cr*?9.0,??(4) S?0.088N*+0.00056,??(5).
    Type: Grant
    Filed: January 7, 2005
    Date of Patent: March 30, 2010
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventors: Shigeru Kidani, Mutsumi Tanida
  • Publication number: 20100006190
    Abstract: A steel pipe is prepared, which contains, by mass, at most 0.009% C, at most 1.0% Mn, at most 1.0% Si, at most 0.04% P, at most 0.005% S, 0.01 to 0.2% Ti, 0.01 to 0.10% V, 0.001 to 0.1% Al, at most 0.1% N, 4.0 to 8.0% Ni, 9.0 to 15.0% Cr, and 1.5 to 7.0% Mo, the balance being Fe and impurities. The prepared steel pipe is bent into a bend pipe. The bend pipe is quenched at a quenching temperature lower than 950° C. The quenched bend pipe is tempered. Accordingly, the bend pipe in accordance with the present invention has excellent SSC resistance.
    Type: Application
    Filed: September 23, 2009
    Publication date: January 14, 2010
    Inventor: Takahiro Oka
  • Publication number: 20090277543
    Abstract: A production system weldable and stainless tubular structures with high mechanical strength and related obtained product, particularly for making tubular elements in cold-drawn stainless steel, workable at different thicknesses and shapes, provided with high performances in terms of mechanical characteristics and weldability, for the construction of light and ultralight structural frames destined for a dynamic use. It comprises a creation step of a tip for making the end of the tube smaller, so that it can pass through the drawing equipment and be coupled for drawing, a step of annealing heat treatment for softening the material and making it deformable.
    Type: Application
    Filed: March 23, 2007
    Publication date: November 12, 2009
    Inventor: Serena Omodeo Sale'
  • Publication number: 20090272469
    Abstract: A steel composition contains: 0.05% or less of C; 0.5% or less of Si; 0.20% to 1.80% of Mn; 0.03% or less of P; 0.005% or less of S; 14.0% to 18.0% of Cr; 5.0% to 8.0% of Ni; 1.5% to 3.5% of Mo; 0.5% to 3.5% of Cu; 0.05% or less of Al; 0.20% or less of V; 0.01% to 0.15% of N; and 0.006% or less of O on a mass basis, and satisfies the following expressions: Cr+0.65Ni+0.6Mo+0.55Cu?20C?18.5 and Cr+Mo+0.3Si?43.5C?0.4Mn?Ni?0.3Cu?9N?11 (where Cr, Ni, Mo, Cu, C, Si, Mn, and N represent their respective contents (mass %)). After such a steel pipe material is formed into a steel pipe, the steel pipe is quenched by cooling after heating to a temperature of the AC3 transformation point or more and tempered at a temperature of the AC1 transformation point or less. The composition may further contain at least one element of Nb and Ti; at least one element selected from the group consisting of Zr, B, and W; or Ca, singly or in combination.
    Type: Application
    Filed: April 2, 2009
    Publication date: November 5, 2009
    Applicant: JFE Steel Corporation, a corporation of Japan
    Inventors: Mitsuo Kimura, Takanori Tamari, Takaaki Toyooka
  • Publication number: 20090246064
    Abstract: The present invention relates to an austenitic stainless steel tube for boiler, used for superheater or reheater in thermal power plant, giving excellent resistance to high temperature steam oxidation, in particular to an austenitic stainless steel tube containing 16 to 20% Cr by weight, and being cold-worked at the inner surface of the tube. The Cr concentration in the vicinity of the inner surface of the steel tube is 14% by weight or larger, and the hardness at 100 ?m depth from the inner surface of the steel tube is 1.5 times or larger the average hardness of the mother material or is HV 300 or larger.
    Type: Application
    Filed: August 23, 2006
    Publication date: October 1, 2009
    Applicant: NKK TUBES
    Inventors: Yusuke Minami, Hitoshi Iijima, Motohisa Yoshida, Toshihiko Fukui, Tatsuo Ono
  • Publication number: 20090101247
    Abstract: A martensitic stainless steel pipe, which comprises specified quantities of C, Si, Mn, P, S, Cr, Ni, Al, N, Cu, Ti, V, Mo, Nb, B and Ca, and the balance being Fe and impurities, has satisfactory toughness at a high strength of 650 MPa or more by yield strength and also excellent hot workability. Therefore, it can be used as a high-strength martensitic stainless steel pipe for carbon dioxide gas corrosion resistant use, to be used in oil and/or gas well environments containing no hydrogen sulfide but carbon dioxide gas. This high-strength martensitic stainless steel pipe is an inexpensive martensitic stainless steel pipe, which does not require an addition of large quantities of expensive elements such as Ni and Mo, and moreover does not require the control of the content of P to a value less than 0.010% by mass.
    Type: Application
    Filed: December 16, 2008
    Publication date: April 23, 2009
    Inventors: Mutsumi Tanida, Nobuyuki Mori, Keiichi Nakamura
  • Patent number: 7485197
    Abstract: In a martensitic stainless steel tube according to the present invention, the content is determined by each of elements C, Si, Mn and Cr, and the bubble content ratio is further prescribed in accordance with the scale thickness on the outer surface of the steel tube, so that defects can be detected with high precision in the non-destructive inspection, such as ultrasonic test or the like. This allows the non-destructive inspection to be carried out with high efficiency. Moreover, there is another advantage that the weather resistance can be enhanced. The steel tube according to the present invention and the manufacturing method thereof can be suitably used in all of the technical fields in which a martensitic stainless steel tube having equal chemical composition is treated.
    Type: Grant
    Filed: March 31, 2006
    Date of Patent: February 3, 2009
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventor: Mutsumi Tanida
  • Patent number: 7475478
    Abstract: A method for making structural automotive components and the like includes providing a blank of air hardenable martensitic stainless steel in the annealed condition. The steel blank has a thickness in the range of 0.5-5.0 mm., and is formed utilizing stamping, forging, pressing, or roller forming techniques or the like into the form of an automotive structural member. The automotive structural member is then hardened by application of heat, preferably to between 950° C. and 1100° C. for standard martensitic stainless steels. Thereafter, the automotive structural member is preferably cooled at a rate greater than 25° C. per minute to achieve a Rockwell C hardness of at least 39. The automotive structural member may undergo additional heat treating processes including high temperature or low temperature tempering processes which may incorporate electro-coating.
    Type: Grant
    Filed: September 11, 2006
    Date of Patent: January 13, 2009
    Assignee: KVA, Inc.
    Inventors: Edward J. McCrink, Danny Codd
  • Patent number: 7470336
    Abstract: A martensitic alloy in which the ASTM grain size number is at least 5, including (wt. %) up to about 0.5% C, at least about 5% Cr, at least about 0.5% Ni, up to about 15% Co, up to about 8% Cu, up to about 8% Mn, up to about 4% Si, up to about 6% (Mo+W), up to about 1.5% Ti, up to about 3% V, up to about 0.5% Al, and at least about 40% Fe.
    Type: Grant
    Filed: October 5, 2007
    Date of Patent: December 30, 2008
    Assignee: Advanced Steel Technology LLC
    Inventor: Robert F. Buck
  • Patent number: 7399372
    Abstract: A metallic bellows, composed of precipitation hardening stainless steel, includes ridge portions and valley portions formed alternately and continuously, an average grain size of 10 to 15 ?m, and compressive residual stress of not less than 500 MPa provided to at least surfaces of the ridge portions and the valleys by surface working.
    Type: Grant
    Filed: November 1, 2004
    Date of Patent: July 15, 2008
    Assignee: NHK Spring Co., Ltd.
    Inventor: Hideki Okada
  • Patent number: 7238434
    Abstract: This invention relates to a welded line pipe structure for transporting corrosive petroleum or natural gas. It is constituted by martensitic stainless steel pipes containing 8–16% Cr and at most 0.05% C. By suitably controlling the welding conditions at the time of girth welding of the steel pipes so as to ensure that the Cr concentration in grain boundary Cr-depleted portions existing immediately beneath a weld oxide scale is at least 5%, the occurrence of SCC in a high temperature CO2 environment can be prevented.
    Type: Grant
    Filed: March 3, 2006
    Date of Patent: July 3, 2007
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventors: Hisashi Amaya, Kazuhiro Ogawa, Kunio Kondo, Masayuki Sagara, Hiroyuki Hirata
  • Patent number: 7232053
    Abstract: The present invention provides seam-welded, air hardenable steel tubes, methods of manufacturing seam-welded air hardenable steel tubes, tube mills for practicing such methods and applications for using seam-welded, air hardenable steel tubing of the present invention.
    Type: Grant
    Filed: June 1, 2005
    Date of Patent: June 19, 2007
    Assignee: KVA, Inc.
    Inventor: Edward J. McCrink
  • Patent number: 7201812
    Abstract: A method for manufacturing a seamless steel tube, wherein a tubing material for the seamless steel tube is produced by a hot working process from a material having less workability, such as a high Cr—high Ni—high C alloy steel including Cr at a content not less than 15 weight % and Ni at a content not less than 20 weight % or a ferritic stainless steel including Cr at a content not less than 16 weight %, and then cold drawn at a reduction rate of not less than 15% and further cold rolled after applying an appropriate heat treatment, so that a round or an inner grooved steel tube is obtained. It is preferable that the hot extrusion process is employed for the hot working process and a cold Pilger mill is employed for the cold rolling process. In the cold rolling process, the crackings or damage resulting from the reduced toughness of the tubing material as well as the breakage of a mandrel in producing the round or the inner grooved tube can be suppressed.
    Type: Grant
    Filed: April 16, 2003
    Date of Patent: April 10, 2007
    Assignee: Sumitomo Metal industries, Ltd.
    Inventor: Hidenori Ogawa
  • Patent number: 7138069
    Abstract: A new surface finishing process for stainless steel where beautiful, bright and milky white coloured surface is obtainable even for such grades as high carbon containing 13 chromium steel and high sulfur containing free cutting stainless steel is disclosed. After removing the surface scale, (1) immerse the stainless steel into the 1st treating solution containing nitric acid: 5–40 g/l, hydrofluoric acid: 2–10 g/l and Fe(III) ion: 15–40 g/l for 5–180 sec., then rinse in water, (2) and successesively immerse into the 2nd treating solution containing nitric acid: 120–250 g/l, Fe(III) ion: 15–40 g/l for 30–300 sec., then rinse in water.
    Type: Grant
    Filed: October 21, 2002
    Date of Patent: November 21, 2006
    Assignee: Parker Corporation
    Inventors: Eiji Sato, Youichi Nakamura
  • Patent number: 7094295
    Abstract: A method of manufacturing a ferritic stainless steel sheet having good workability with less anisotropy. The steps include providing a ferritic stainless steel comprising C up to about 0.03 mass %, N up to about 0.03 mass %, Si up to about 2.0 mass %, Mn up to about 2.0 mass %, Ni up to about 0.6 mass %, Cr about 9–35 mass %, Nb about 0.15–0.80 mass % and the balance being Fe except inevitable impurities; precipitation-heating said stainless steel at a temperature in a range of 700–850° C. for a time period not longer than 25 hours; and finish-annealing said stainless steel at a temperature in a range of 900–1100° C. for a time period not longer than 1 minute.
    Type: Grant
    Filed: October 28, 2003
    Date of Patent: August 22, 2006
    Assignee: Nisshin Steel Co., Ltd.
    Inventors: Manabu Oku, Yoshitomo Fujimura, Yoshiaki Hori, Toshirou Nagoya, Yasutoshi Kunitake, Takeo Tomita
  • Patent number: 6899773
    Abstract: An iron based, fine-grained, martensitic stainless steel essentially free of delta ferrite has a nominal composition of (wt. %): 0.05<C<0.15; 7.5<Cr<15; 2<Ni<5; Co<4; Cu<1.2; Mn<5; Si<1; (Mo+W)<4; 0.01<Ti<0.75; 0.135<(1.17Ti+0.6Zr+0.31Ta+0.31Hf)<1; V<2; Nb<1; N<0.02; Al<0.2; Al and Si both present such that (Al+Si)>0.01; B<0.1; P<0.1; S<0.03; and the balance essentially iron and impurities. This steel is different from other martensitic stainless steels because thermal mechanical treatment is used to refine the grains and precipitate a relatively uniform dispersion of fine, coarsening-resistant, MX-type particles. The steel combines high strength and impact toughness with good corrosion resistance.
    Type: Grant
    Filed: May 8, 2003
    Date of Patent: May 31, 2005
    Assignee: Advanced Steel Technology, LLC
    Inventor: Robert F. Buck
  • Patent number: 6890665
    Abstract: Martensitic stainless steel whose steel composition is restricted within a specific range for each element is provided. The scale layer formed on the surface of the base material consists of an inner layer scale mainly including FeCr2O4 and an outer layer scale having a thickness of not more than 20 ?m, which outer layer is deposited on the inner layer scale at a surface coverage of not less than 1% and not more than 15%. The application of rust preventive oil onto the surface of the steel ensures an excellent weather resistance during a long term, and therefore a martensitic stainless steel forming no rust either in the outdoor depository or in the indoor depository can be provided. The steel can be used to manufacture, not only steel pipes, but also steel plates, steel rods and others in a wide application field.
    Type: Grant
    Filed: September 26, 2003
    Date of Patent: May 10, 2005
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventor: Mutsumi Tanida
  • Patent number: 6890393
    Abstract: An iron based, fine-grained, alloy.
    Type: Grant
    Filed: November 12, 2003
    Date of Patent: May 10, 2005
    Assignee: Advanced Steel Technology, LLC
    Inventor: Robert F. Buck
  • Patent number: 6887322
    Abstract: High pressure cylinders comprising backing steel cylinders and tool steel liners are disclosed. An annealed tool steel liner is inserted into the backing steel cylinder, followed by heat treating to harden the tool steel liner. The tool steel liner may be provided as a single continuous tube, thereby avoiding problems associated with segmented liners. The high-pressure cylinders are suitable for use as plastic and rubber extruders injection molding cylinders and the like.
    Type: Grant
    Filed: April 9, 2002
    Date of Patent: May 3, 2005
    Assignee: Wexco Corporation
    Inventors: Donald W. Smith, Calvin D. Lundeen