With Working Patents (Class 148/584)
  • Patent number: 11566307
    Abstract: Provided is a rail that is effective in improving wear resistance and rolling contact fatigue (RCF) resistance. The rail has a metallic structure including a pearlitic structure and a structure other than the pearlitic structure in a surface layer from a surface of a rail head to a depth of at least 0.5 mm, where the pearlitic structure has Vickers hardness of 420 HV or more and 520 HV or less, and the structure other than the pearlitic structure has Vickers hardness of 350 HV or more and 420 HV or less.
    Type: Grant
    Filed: March 25, 2019
    Date of Patent: January 31, 2023
    Assignee: JFE STEEL CORPORATION
    Inventors: Minoru Honjo, Mineyasu Takemasa
  • Patent number: 11306377
    Abstract: The present invention provides a high strength, high toughness, heat-cracking resistant bainite steel wheel for rail transportation and a manufacturing method thereof. Components are: carbon 0.10-0.40%, silicon 1.00-2.00%, manganese 1.00-2.50%, copper 0.20-1.00%, boron 0.0001-0.035%, nickel 0.10-1.00%, phosphorus ?0.020%, and sulphur ?0.020%, where the remaining is iron and unavoidable residual elements, 1.50%?Si+Ni?3.00%, and 1.50%?Mn+Ni+Cu?3.00%. Compared with the prior art, in the present invention, by using design of the chemical compositions of steel and wheel manufacturing processes, especially a heat treatment process and technology, a rim of the wheel obtains a carbide-free bainite structure, and a web and a wheel hub obtain a metallographic structure based on granular bainite and a supersaturated ferritic structure.
    Type: Grant
    Filed: July 6, 2017
    Date of Patent: April 19, 2022
    Assignees: MAGANG (GROUP) HOLDING CO., LTD., MAANSHAN IRON & STEEL CO., LTD.
    Inventors: Mingru Zhang, Zheng Fang, Feng Zhang, Chaohai Yin, Yumei Pu, Zhiyuan Cheng, Hai Zhao
  • Patent number: 10870165
    Abstract: The invention discloses a mobile flash butt welding method for 136RE+SS heat-treated rail, and particularly a mobile flash butt welding method for 136RE+SS heat-treated rail in the technical field of rail welding. The mobile flash butt welding method for 136RE+SS heat-treated rail in the invention includes a pre-flash stage, a flash stage, a boost stage, an upset stage and a forge stage, with a total heat input of 7.1 MJ-10.0 MJ, a total duration of 110 s-135 s and an upsetting distance of 12.8 mm-16.7 mm during the welding process. By adopting the method of the invention, mobile flash butt welding can be conducted for 136RE+SS heat-treated rail successfully, and the rail joint has less internal defects but stable welding quality, and can pass fatigue test, tensile test and slow bend test to meet the requirements. Besides, the rail joint can pass the drop weight test for 15 welds continuously, demonstrating better stability.
    Type: Grant
    Filed: August 24, 2018
    Date of Patent: December 22, 2020
    Assignee: Pangang Group Research Institute Co., Ltd.
    Inventors: Xin Lu, Dadong Li, Ruoyu Wang, Wei Bai, Jian Deng, Feixiang Xu
  • Patent number: 10851432
    Abstract: The present invention discloses an ultra-high strength and ultra-high toughness casing steel, having a microstructure of tempered sorbite, and the content of chemical elements by mass percent thereof being as follows: C: 0.1-0.22%, Si: 0.1-0.4%, Mn: 0.5-1.5%, Cr: 1-1.5%, Mo: 1-1.5%, Nb: 0.01-0.04%, V: 0.2-0.3%, Al: 0.01-0.05%, Ca: 0.0005-0.005%, the balance being Fe and unavoidable impurities. Correspondingly, the invention also discloses a casing obtained by processing the ultra-high strength and ultra-high toughness casing steel and a manufacturing method thereof. The ultra-high strength and ultra-toughness casing steel and the casing of the present invention have a strength of 155 ksi or more and an impact toughness greater than 10% of its yield strength value, thereby realizing a combination of ultra-high strength and ultra-high toughness.
    Type: Grant
    Filed: June 17, 2016
    Date of Patent: December 1, 2020
    Assignee: BAOSHAN IRON & STEEL CO., LTD.
    Inventors: Xiaoming Dong, Zhonghua Zhang, Xiaodong Jin
  • Patent number: 10850315
    Abstract: Provided is a manufacturing method for high-toughness and plasticity hypereutectoid rail, including: a. hot rolling the steel billet into rail; b. blowing a cooling medium to the top surface of railhead, wherein, the two sides of railhead and the lower jaws on the two sides of railhead after the center of top surface of rail is air-cooled to 800-850° C., and cooling the rail until the center temperature of the top surface is 520-550° C.; c. stop blowing the cooling medium to the lower jaws on the two sides of railhead, continue blowing the cooling medium to the top surface of railhead and the two sides of railhead, and air cool the rail to room temperature after the surface temperature of railhead is cooled to 430-480° C. The resulting hypereutectoid rail has higher toughness and plasticity than existing products, which is suitable for heavy-haul railway, especially for small radius curve sections.
    Type: Grant
    Filed: October 9, 2018
    Date of Patent: December 1, 2020
    Assignee: Pangang Group Research Institute Co., Ltd.
    Inventors: Zhenyu Han, Ming Zou, Hua Guo, Jun Yuan
  • Patent number: 10253397
    Abstract: A pearlitic rail includes a composition including in % by mass: 0.70% to 0.90% of C; 0.1% to 1.5% of Si; 0.01% to 1.5% of Mn; 0.001% to 0.035% of P; 0.0005% to 0.030% of S; 0.1% to 2.0% of Cr, remainder of the composition consisting of Fe and inevitable impurities. Surface hardness of a rail top is not less than HB 430, and hardness at a depth of 25 mm from a surface of the rail top is not less than HB 410.
    Type: Grant
    Filed: March 25, 2014
    Date of Patent: April 9, 2019
    Assignee: JFE Steel Corporation
    Inventors: Tatsumi Kimura, Kiyoshi Uwai, Shigeru Endo, Moriyasu Yamaguchi
  • Patent number: 9157131
    Abstract: A high carbon content and high strength heat-treated steel rail including by weight 0.80-1.20% carbon, 0.20-1.20% silicon, 0.20-1.60% manganese, 0.15-1.20% chromium, 0.01-0.20% vanadium, 0.002-0.050% titanium, less than or equal to 0.030% phosphorus, less than or equal to 0.030% sulfur, less than or equal to 0.010% aluminum, less than or equal to 0.0100% nitrogen, and iron. The steel rail has excellent wear resistance and plasticity and can satisfy the requirement for overloading. A method for producing the steal rail by heating a slab to a heating temperature, multi-pass rolling, and accelerated cooling, wherein a maximum heating temperature (° C.) of said slab is equal to 1,400 minus 100[% C], [% C] representing the carbon content (wt. %) of said slab multiplied by 100.
    Type: Grant
    Filed: November 23, 2010
    Date of Patent: October 13, 2015
    Assignees: PANGANG GROUP CO., LTD., PANGANG GROUP RESEARCH INSTITUTE CO., LTD., PANGANG GROUP PANZHIHUA STEEL & VANADIUM CO., LTD.
    Inventors: Ming Zou, Dongsheng Mei, Quan Xu, Yong Deng, Hua Guo, Ming Liu, Li Tang, Yun Zhao, Gongming Tao
  • Patent number: 8980019
    Abstract: A steel rail includes: by mass %, higher than 0.85% to 1.20% of C; 0.05% to 2.00% of Si; 0.05% to 0.50% of Mn; 0.05% to 0.60% of Cr; P?0.0150%; and the balance consisting of Fe and inevitable impurities, wherein 97% or more of a head surface portion which is in a range from a surface of a head corner portion and a head top portion as a starting point to a depth of 10 mm has a pearlite structure, a Vickers hardness of the pearlite structure is Hv320 to 500, and a CMn/FMn value which is a value obtained by dividing CMn [at. %] that is a Mn concentration of a cementite phase in the pearlite structure by FMn [at. %] that is a Mn concentration of a ferrite phase is equal to or higher than 1.0 and equal to or less than 5.0.
    Type: Grant
    Filed: June 7, 2011
    Date of Patent: March 17, 2015
    Assignee: Nippon Steel & Sumitomo Metal Corporation
    Inventors: Masaharu Ueda, Jun Takahashi, Akira Kobayashi, Takuya Tanahashi
  • Patent number: 8747576
    Abstract: This high-carbon pearlitic steel rail having excellent ductility, includes: in terms of percent by mass, C: more than 0.85% to 1.40%; Si: 0.10% to 2.00%; Mn: 0.10% to 2.00%; Ti: 0.001% to 0.01%; V: 0.005% to 0.20%; and N: less than 0.0040%, with the balance being Fe and inevitable impurities, wherein contents of Ti and V fulfill the following formula (1), and a rail head portion has a pearlite structure.
    Type: Grant
    Filed: April 14, 2010
    Date of Patent: June 10, 2014
    Assignee: Nippon Steel & Sumitomo Metal Corporation
    Inventors: Teruhisa Miyazaki, Masaharu Ueda, Suguru Yoshida
  • Patent number: 8585835
    Abstract: A high-strength steel machined product giving excellent hardenability has a metal microstructure with excellent balance of strength and toughness and high stability of retained austenite. The product is composed of an ultra-high low-alloy TRIP steel having a metal microstructure which contains an appropriate quantity of two or more of Cr, Mo, and Ni, and an appropriate quantity of one or more of Nb, Ti, and V, and having an appropriate value of carbon equivalent; the metal microstructure has a mother-phase structure composed mainly of lathy bainitic ferrite with a small amount of granular bainitic ferrite and polygonal ferrite, and has a secondary-phase structure composed of fine retained austenite and martensite.
    Type: Grant
    Filed: October 29, 2009
    Date of Patent: November 19, 2013
    Assignees: Usui Kokusai Sangyo Kaisha Limited, Shinshu University
    Inventors: Koh-ichi Sugimoto, Sho-hei Sato, Teruhisa Takahashi, Goro Arai
  • Patent number: 8557065
    Abstract: A high-strength, high-workability steel sheet for cans contains 0.070% to less than 0.080% C, 0.003% to 0.10% Si, 0.51% to 0.60% Mn, and the like on a mass basis and has a tensile strength of 500 MPa or more and a yield elongation of 10% or more. The average size and elongation rate of crystal grains are 5 ?m or more and 2.0 or less, respectively, in cross section in the rolling direction thereof. The hardness difference obtained by subtracting the average Vickers hardness of a cross section ranging from a surface to a depth equal to one-eighth of the thickness of the sheet from the average Vickers hardness of a cross section ranging from a depth equal to three-eighths of the sheet thickness to a depth equal to four-eighths of the sheet thickness is 10 points or more and/or the maximum Vickers hardness difference is 20 points or more.
    Type: Grant
    Filed: November 29, 2010
    Date of Patent: October 15, 2013
    Assignee: JFE Steel Corporation
    Inventors: Masaki Tada, Takumi Tanaka, Katsumi Kojima, Hiroki Iwasa
  • Publication number: 20130206855
    Abstract: Methods, systems, and apparatus, including an apparatus that is a rail anchor comprising a head, a tail, and a belly section. The belly section comprises a top surface, a bottom surface, and two side surfaces. Each side surface comprises a contact-bearing surface area. The head comprises a bend along a length of the head. The tail comprises a notch. Each contact-bearing surface area has a surface area of at least 3 square inches and is adapted to extend at least 1.5 inches downward from the top of a railroad track crosstie along a side of the railroad track crosstie.
    Type: Application
    Filed: May 26, 2011
    Publication date: August 15, 2013
    Inventors: David M. Barry, Timothy John Austin, Luigi Pisano
  • Patent number: 8469284
    Abstract: This pearlitic rail consists of a steel including: in terms of percent by mass, C: 0.65% to 1.20%; Si: 0.05% to 2.00%; Mn: 0.05% to 2.00%; and REM: 0.0005% to 0.0500%, with the balance being Fe and inevitable impurities, wherein, in a head portion of the rail, a head surface portion which ranges from surfaces of head corner portions and a head top portion to a depth of 10 mm has a pearlite structure, and the hardness Hv of the head surface portion is in a range of 320 to 500.
    Type: Grant
    Filed: January 21, 2010
    Date of Patent: June 25, 2013
    Assignee: Nippon Steel & Sumitomo Metal Corporation
    Inventors: Masaharu Ueda, Takashi Morohoshi, Kazunori Seki
  • Publication number: 20130065079
    Abstract: A steel rail includes: by mass %, higher than 0.85% to 1.20% of C; 0.05% to 2.00% of Si; 0.05% to 0.50% of Mn; 0.05% to 0.60% of Cr; P?0.0150%; and the balance consisting of Fe and inevitable impurities, wherein 97% or more of a head surface portion which is in a range from a surface of a head corner portion and a head top portion as a starting point to a depth of 10 mm has a pearlite structure, a Vickers hardness of the pearlite structure is Hv320 to 500, and a CMn/FMn value which is a value obtained by dividing CMn [at. %] that is a Mn concentration of a cementite phase in the pearlite structure by FMn [at. %] that is a Mn concentration of a ferrite phase is equal to or higher than 1.0 and equal to or less than 5.0.
    Type: Application
    Filed: June 7, 2011
    Publication date: March 14, 2013
    Inventors: Masaharu Ueda, jun Takahashi, Akira Kobayashi, Takuya Tanahashi
  • Patent number: 8367960
    Abstract: A method for restoring a worn rail section includes cleaning a worn surface of a rail section to expose a clean metal surface, heating the rail section to a first temperature before welding, welding new metal on the clean metal surface of the rail section after heating the rail section to the first temperature, heating the rail section to a second temperature after the welding to heat-treat a heat-affected area caused by the welding, and shaping the rail section, wherein the welding is performed by a gas metal arc welding (GMAW) process.
    Type: Grant
    Filed: June 6, 2011
    Date of Patent: February 5, 2013
    Assignee: CSX Transportation
    Inventor: Rod Keefe
  • Publication number: 20110253268
    Abstract: A high carbon content and high strength heat-treated steel rail including by weight 0.80-1.20% carbon, 0.20-1.20% silicon, 0.20-1.60% manganese, 0.15-1.20% chromium, 0.01-0.20% vanadium, 0.002-0.050% titanium, less than or equal to 0.030% phosphorus, less than or equal to 0.030% sulfur, less than or equal to 0.010% aluminum, less than or equal to 0.0100% nitrogen, and iron. The steel rail has excellent wear resistance and plasticity and can satisfy the requirement for overloading. A method for producing the steal rail by heating a slab to a heating temperature, multi-pass rolling, and accelerated cooling, wherein a maximum heating temperature (° C.) of said slab is equal to 1,400 minus 100[% C], [% C] representing the carbon content (wt. %) of said slab multiplied by 100.
    Type: Application
    Filed: November 23, 2010
    Publication date: October 20, 2011
    Applicants: PANGANG GROUP CO., LTD., PANGANG GROUP PANZHIHUA STEEL & VANADIUM CO., LTD., PANGANG GROUP RESEARCH INSTITUTE CO., LTD.
    Inventors: Ming ZOU, Dongsheng MEI, Quan XU, Yong DENG, Hua GUO, Ming LIU, Li TANG, Yun ZHAO, Gongming TAO
  • Patent number: 7972451
    Abstract: The present invention is: a pearlitic steel rail excellent in wear resistance and ductility, characterized in that, in a steel rail having pearlite structure containing, in mass, 0.65 to 1.40% C, the number of the pearlite blocks having grain sizes in the range from 1 to 15 ?m is 200 or more per 0.2 mm2 of an observation field at least in a part of the region down to a depth of 10 mm from the surface of the corners and top of the head portion; and a method for producing a pearlitic steel rail excellent in wear resistance and ductility, characterized by, in the hot rolling of said steel rail, applying finish rolling so that the temperature of the rail surface may be in the range from 850° C. to 1,000° C. and the sectional area reduction ratio at the final pass may be 6% or more, and then applying accelerated cooling to the head portion of said rail at a cooling rate in the range from 1 to 30° C./sec. from the austenite temperature range to at least 550° C.
    Type: Grant
    Filed: July 19, 2007
    Date of Patent: July 5, 2011
    Assignee: Nippon Steel Corporation
    Inventors: Masaharu Ueda, Koichiro Matsushita, Kazuo Fujita, Katsuya Iwano, Koichi Uchino, Takashi Morohoshi, Akira Kobayashi
  • Patent number: 7955445
    Abstract: An internal high hardness type pearlitic rail that has a composition containing 0.73% to 0.85% by mass C, 0.5% to 0.75% by mass Si, 0.3% to 1.0% by mass Mn, 0.035% by mass or less P, 0.0005% to 0.012% by mass S, 0.2% to 1.3% by mass Cr, and the balance being Fe and incidental impurities, in which the value of [% Mn]/[% Cr] is greater than or equal to 0.3 and less than 1.0, where [% Mn] represents the Mn content, and [% Cr] represents the Cr content, and in which the internal hardness of a rail head that is defined by the Vickers hardness of a portion located from a surface layer of the rail head to a depth of at least 25 mm is greater than or equal to 380 Hv and less than 480 Hv.
    Type: Grant
    Filed: March 25, 2008
    Date of Patent: June 7, 2011
    Assignee: JFE Steel Corporation
    Inventors: Minoru Honjo, Tatsumi Kimura, Shinichi Suzuki, Kimihiro Nishimura, Shinji Mitao, Nobuo Shikanai
  • Patent number: 7828917
    Abstract: A rail manufacturing method is provided, in which a billet is hot-rolled into a rail form and the rail is cooled to ambient temperature. The foot part of the rail can be mechanically restrained to improve the straightness of the rail during at least the period of cooling where the surface temperature is between 800° C. and 400° C. In the subsequent cooling process, at least while the surface temperature of the foot of the rail is between 400° C. and 250° C., the rail is kept in an upright state, and cooled naturally without using insulation or accelerated cooling.
    Type: Grant
    Filed: January 7, 2005
    Date of Patent: November 9, 2010
    Assignee: Nippon Steel Corporation
    Inventors: Noriaki Onodera, Takuya Satoh, Masaharu Ueda, Kazuo Fujita, Akira Kobayashi
  • Publication number: 20100186857
    Abstract: An internal high hardness type pearlitic rail has a composition containing 0.73% to 0.85% by mass C, 0.5% to 0.75% by mass Si, 0.3% to 1.0% by mass Mn, 0.035% by mass or less P, 0.0005% to 0.012% by mass S, 0.2% to 1.3% by mass Cr, 0.005% to 0.12% by mass V, 0.0015% to 0.0060% by mass N, and the balance being Fe and incidental impurities, wherein the value of [% Mn]/[% Cr] is greater than or equal to 0.3 and less than 1.0, where [% Mn] represents the Mn content, and [% Cr] represents the Cr content, and the value of [% V]/[% N] is in the range of 8.0 to 30.0, where [% V] represents the V content, and [% N] represents the N content, and wherein the internal hardness of a rail head is defined by the Vickers hardness of a portion located from a surface layer of the rail head to a depth of at least 25 mm and is greater than or equal to 380 Hv and less than 480 Hv.
    Type: Application
    Filed: March 25, 2008
    Publication date: July 29, 2010
    Applicant: JFE STEEL CORPORATION
    Inventors: Minoru Honjo, Tatsumi Kimura, Shinichi Suzuki, Kimihiro Nishimura, Nobuo Shikanai
  • Publication number: 20100116381
    Abstract: An internal high hardness type pearlitic rail that has a composition containing 0.73% to 0.85% by mass C, 0.5% to 0.75% by mass Si, 0.3% to 1.0% by mass Mn, 0.035% by mass or less P, 0.0005% to 0.012% by mass S, 0.2% to 1.3% by mass Cr, and the balance being Fe and incidental impurities, in which the value of [% Mn]/[% Cr] is greater than or equal to 0.3 and less than 1.0, where [% Mn] represents the Mn content, and [% Cr] represents the Cr content, and in which the internal hardness of a rail head that is defined by the Vickers hardness of a portion located from a surface layer of the rail head to a depth of at least 25 mm is greater than or equal to 380 Hv and less than 480 Hv.
    Type: Application
    Filed: March 25, 2008
    Publication date: May 13, 2010
    Applicant: JFE STEEL CORPORATION
    Inventors: Minoru Honjo, Tatsumi Kimura, Shinichi Suzuki, Kimihiro Nishimura, Shinji Mitao, Nobuo Shikanai
  • Patent number: 7416622
    Abstract: In order to obtain a fine-lamellar perlite structure in the edge region of the heads of rails (1), especially hot-rolled rails for carriageways or railways, by specific thermal treatment during cooling from the rolling heat without the formation of bainite, precooling (12) occurs in order to achieve a core temperature of approximately 750-850° C., and the temperature of the more intensively cooled edge region is raised by intermediate heating (13) to at least said core temperature and finally cooled (14).
    Type: Grant
    Filed: September 19, 2002
    Date of Patent: August 26, 2008
    Assignee: SMS Meer GmbH
    Inventors: Klaus Küppers, Meinert Meyer, Thomas Nerzak
  • Patent number: 7288159
    Abstract: An improved steel railroad rail, and methods for producing same, having a high-carbon content in a range from more than 0.9 to 1.1 wt % is provided that has increased wear resistance and increased fracture toughness over conventional steel rail. The high-carbon rail is characterized as having a pearlitic phase of an eutectoid nature. The average ultimate tensile strength is in a range from 204,860 to 222,120 psi, with a minimum of 174,000 psi. The average yield strength is in a range from 132,320 to 148,450 psi, with the minimum of 120,000 psi. The average percent elongation is in a range from 10.50 to 11.14, with a minimum of 10.00. The Brinell hardness on the surface at any position of the head top and upper gage corners of the rail is in a range from 390 to 440 BHN. The hardness 19 mm below the top surface is in a range from 360 to 435 BHN and 19 mm below the surface at the upper gage corners is in a range from 360 to 410 BHN.
    Type: Grant
    Filed: April 10, 2002
    Date of Patent: October 30, 2007
    Assignee: CF&I Steel, L.P.
    Inventor: J. Vincent Cordova
  • Patent number: 7217329
    Abstract: An improved steel railroad rail, and methods for producing same, having a carbon content in a range from 0.7 to 0.95 wt % and titanium in the range of 0.005 to 0.105 wt % is provided that has increased wear resistance and increased fracture toughness over conventional steel rail. The rail is characterized as having a pearlitic phase of an eutectoid nature. The average ultimate tensile strength is in a range from 178,000 to 207,000 psi, with a minimum of 174,000 psi. The average yield strength is in a range from 122,000 to 141,000 psi, with the minimum of 120,000 psi. The average percent elongation is in a range from 10.3 to 12.5, with a minimum of 10.00. The Brinell hardness on the surface at any position of the head top and upper gage corners of the rail is in a range from 370 to 420 BHN. The hardness 19 mm below the top surface is in a range from 360 to 405 BHN and 19 mm below the surface at the upper gage corners is in a range from 360 to 410 BHN.
    Type: Grant
    Filed: August 26, 2002
    Date of Patent: May 15, 2007
    Assignee: CF&I Steel
    Inventor: J. Vincent Cordova
  • Patent number: 7143499
    Abstract: The invention relates to a method for producing metal strips and sheets involving the following method steps: pouring a strand, which is provided in the form (1) of thin slabs and which is comprised of carbon steel or special steel, into a casting machine (4) and rolling the cast product away from the casting heat. The aim of the invention is to utilize free capacities of existing installations, that is, installations not operating at full capacity, with which primary carbon steels are produced, in order to supplement other types of steel or to supplement cast products produced in another manner. To this end, the invention provides that, together with these first cast products (1), at least second cast products (2), which are produced in a second process route (II) from special steel if the first thin slabs are cast from carbon steel or are produced from carbon steel if the first thin slabs are cast from special steel, are rolled within a joint rolling program.
    Type: Grant
    Filed: August 23, 2001
    Date of Patent: December 5, 2006
    Assignee: SMS Demag AG
    Inventors: Jürgen Seidel, Günter Kneppe, Joachim Hafer
  • Publication number: 20040211064
    Abstract: A method of manufacturing a structural member of a vehicle includes the steps of preparing a steel essentially including Fe, 0.20-0.25 weight % of C, not more than 0.3 weight % of Si, 1.0-1.2 weight % of Mn, not more than 0.02 weight % of P, and not more than 0.005 weight % of S. The method includes forming a structural member by pressing the steel and heat treating a portion of the structural member where a supplementary reinforcement is required for enhancing the strength of the structural member. The heat treating is performed by means of direct-heating, whereby a traditional reinforcing process can be eliminated and the weight of the structural member can be reduced.
    Type: Application
    Filed: December 31, 2003
    Publication date: October 28, 2004
    Inventor: Doo Hwan Lee
  • Publication number: 20040187981
    Abstract: The present invention is: a pearlitic steel rail excellent in wear resistance and ductility, characterized in that, in a steel rail having pearlite structure containing, in mass, 0.65 to 1.40% C, the number of the pearlite blocks having grain sizes in the range from 1 to 15 &mgr;m is 200 or more per 0.2 mm2 of an observation field at least in a part of the region down to a depth of 10 mm from the surface of the corners and top of the head portion; and a method for producing a pearlitic steel rail excellent in wear resistance and ductility, characterized by, in the hot rolling of said steel rail, applying finish rolling so that the temperature of the rail surface may be in the range from 850° C. to 1,000° C. and the sectional area reduction ratio at the final pass may be 6% or more, and then applying accelerated cooling to the head portion of said rail at a cooling rate in the range from 1 to 30° C./sec. from the austenite temperature range to at least 550° C.
    Type: Application
    Filed: December 29, 2003
    Publication date: September 30, 2004
    Inventors: Masaharu Ueda, Koichiro Matsushita, Kazuo Fujita, Katsuya Iwano, Koichi Uchino, Takashi Morohoshi, Akira Kobayashi
  • Publication number: 20040035507
    Abstract: An improved steel railroad rail, and methods for producing same, having a carbon content in a range from 0.7 to 0.95 wt % and titanium in the range of 0.005 to 0.105 wt % is provided that has increased wear resistance and increased fracture toughness over conventional steel rail. The rail is characterized as having a pearlitic phase of an eutectoid nature. The average ultimate tensile strength is in a range from 178,000 to 207,000 psi, with a minimum of 174,000 psi. The average yield strength is in a range from 122,000 to 141,000 psi, with the minimum of 120,000 psi. The average percent elongation is in a range from 10.3 to 12.5, with a minimum of 10.00. The Brinell hardness on the surface at any position of the head top and upper gage corners of the rail is in a range from 370 to 420 BHN. The hardness 19 mm below the top surface is in a range from 360 to 405 BHN and 19 mm below the surface at the upper gage corners is in a range from 360 to 410 BHN.
    Type: Application
    Filed: August 26, 2002
    Publication date: February 26, 2004
    Inventor: J. Vincent Cordova
  • Publication number: 20030168135
    Abstract: The present invention provides a method and equipment for producing a rail, the method and equipment being capable of lowering a bend at an end of a rail effectively and the truncation amount thereof. The present invention is a method for producing a rail, characterized by: cooling a hot-rolled mother rail to an ordinary temperature substantially while the length thereof after the hot rolling is maintained; and thereafter cutting the mother rail simultaneously in a predetermined length with at least three cold-sawing machines. Further, the present invention is equipment for producing a rail, characterized by equipped with: a transfer bed capable of moving a mother rail cooled to an ordinary temperature substantially while the length thereof after hot rolling is maintained in the rolling direction and/or in the direction perpendicular to the rolling direction; and at least three cold-sawing machines disposed in parallel with each other on said transfer bed.
    Type: Application
    Filed: February 19, 2003
    Publication date: September 11, 2003
    Inventors: Noriaki Onodera, Masafumi Shibata, Masanori Miwa, Kazuo Fujita
  • Publication number: 20020134472
    Abstract: A process for the manufacture of a railroad rail of a steel alloy having a pearlitic microstructure. The rail is is shaped at a reduction rate of 1.8 to 8% and aligned straight in its longitudinal direction at a temperature between 770° C. and 1050° C., whereafter it is mounted with the head down and is allowed to cool slowly in still air to a temperature of 5 to 120° C. above the Ar3 temperature, and upon reaching this temperature at least the rail head is dipped into a cooling liquid and is cooled to the temperature of conversion of an austenitic grain microstructure into a fine pearlitic grain microstructure.
    Type: Application
    Filed: February 15, 2002
    Publication date: September 26, 2002
    Inventors: Georg Prskawetz, Peter Pointner, Alfred Moser
  • Patent number: 6315844
    Abstract: The invention relates to a high-strength steel track element, and process of making the steel track element by rolling and heat treating. The steel comprises: 0.3-0.6% C, 0.8-1.5% Si, 0.7-1.0% Mn, 0.9-1.4% Cr, 0.6-1.0% Mo, balance iron and smelting-related impurities. The steel has a bainitic basic structure, a tensile strength of at least 1600 N/mm2 and a technical yield strength of at least 1250 N/mm2.
    Type: Grant
    Filed: April 19, 2000
    Date of Patent: November 13, 2001
    Assignee: BWG Butzbacher Weichenbau Gesellschaft mbH & Co. KG
    Inventors: Gerhard Ratz, Walter Kunitz
  • Publication number: 20010035241
    Abstract: A method for forming a titanium nitride film of an excellent quality on a semiconductor substrate at a low temperature is achieved. With a heated semiconductor substrate on a susceptor held at a temperature of about 500° C., titanium tetrachloride and ammonia are introduced into a reactor to carry out the deposition of the titanium nitride film. After the deposition is completed, the semiconductor substrate within the reactor is continuously held at a temperature of 500° C. After a low pressure mercury lamp is turned on, while the inner part of the reactor is irradiated with ultraviolet rays with a wavelength of 170-280 nm emitted from the lamp, an ammonia gas is introduced, with the flow rate adjusted to about 1000 sccm, into the reactor held at a pressure of about 10 Torr to carry out annealing in an ammonia atmosphere for about 60 seconds.
    Type: Application
    Filed: May 26, 1999
    Publication date: November 1, 2001
    Inventor: KOICHI OHTO
  • Patent number: 6224694
    Abstract: Method for heat-treating profiled rolling stock, including track and railroad rails, having a profiled surface and increased heat removal from portions of the profiled surface during cooling in the gamma range of an iron based alloy material. The method includes aligning the profiled rolling stock, at an average temperature of between 750° C. and 1100° C., straight in its longitudinal direction by plastic shaping, and moving the aligned profiled rolling stock, in its aligned state, in a transverse direction and holding same there. The method also includes evenly cooling of the aligned profiled rolling stock, in a first cooling, to a temperature below 860° C.
    Type: Grant
    Filed: May 12, 2000
    Date of Patent: May 1, 2001
    Assignee: Voest Alpine Schienen GmbH & Co., KG
    Inventors: Georg Prskawetz, Peter Pointner, Alfred Moser
  • Patent number: 5830286
    Abstract: This invention provides a steel rail having wear resistance and internal breakage resistance required for a heavy load railway, containing, in terms of percent by weight, more than 0.85 to 1.20% of C, 0.10 to 1.00% of Si, 0.40 to 1.50% of Mn, 0.0005 to 0.0040% of B, at least one of 0.05 to 1.00% of Cr, 0.01 to 0.50% of Mo, 0.02 to 0.30% of V, 0.002 to 0.05% of Nb and 0.10 to 2.00% of Co, whenever necessary, being acceleratedly cooled at a cooling rate of 5.degree. to 15.degree. C./sec from an austenite zone temperature to 650.degree. to 500.degree. C., exhibiting a pearlite structure having a hardness of at least Hv 370 within the range from the surface of the rail head portion to a position having a depth of 20 mm from the head surface with this head surface being the start point, and the difference of the hardness within this range being not more than Hv 30.
    Type: Grant
    Filed: November 13, 1996
    Date of Patent: November 3, 1998
    Assignee: Nippon Steel Corporation
    Inventors: Masaharu Ueda, Kouichi Uchino
  • Patent number: 5759299
    Abstract: A high-abrasion bainite rail excellent in resistance to rolling fatigue and failure, consisting essentially of 0.15 to 0.55 wt. % of C, 0.05 to 1.0 wt. % of Si, 0.1 to 2.5 wt. % of Mn, 0.03 wt. % or less of P, 0.03 wt. % or less of S, 0.1 to 3.0 wt. % of Cr, 0.005 to 2.05 wt. % of Mo, and the balance being iron and inevitable impurities. The head portion of the rail has a uniform bainite structure. The Vickers hardness at any position of the head top portion and the head corner portion is 240 to 400 Hv. A rail of high toughness and high wear resistance, consisting essentially of 0.2 to 0.5 wt. % of C, 0.1 to 2.0 wt. % of Si, 1.0 to 3.0 wt. % of Mn, 0.035 wt. % or less of P, 0.035 wt. % or less of S, 0.3 to 4.0 wt. % of Cr, and the balance being iron and inevitable impurities.
    Type: Grant
    Filed: July 29, 1996
    Date of Patent: June 2, 1998
    Assignee: NKK Corporation
    Inventors: Hiroyasu Yokoyama, Sadahiro Yamamoto, Kazutaka Kobayashi
  • Patent number: 5711914
    Abstract: The properties of conventional steels for rails, check rails and railroad rolling components can be improved by small amounts of tellurium. This applies particularly to the wear resistance and the mechanical properties in the transverse direction and at oxygen contents of less than 0.0015% and sulfur contents up to 0.007%.
    Type: Grant
    Filed: November 18, 1994
    Date of Patent: January 27, 1998
    Assignee: NMH Stahwerke GmbH
    Inventor: Wilhelm Heller
  • Patent number: 5658400
    Abstract: High-carbon pearlitic steel rails have high strength, wear resistance, ductility and toughness are manufactured by applying special rolling to produce fine-grained pearlite blocks in steels containing 0.60 to 1.20% carbon, 0.10 to 1.20 % silicon, 0.40 to 1.50% manganese and one or more elements selected, as required, from the group of chromium, molybdenum, vanadium, niobium and cobalt, thus imparting high wear resistance and an elongation of not less than 12% and a V notch Charpy impact value of not lower than 25 J/cm.sup.2. The high-carbon rails having high wear resistance, ductility and toughness assure safe railroad services in cold districts.
    Type: Grant
    Filed: August 15, 1995
    Date of Patent: August 19, 1997
    Assignee: Nippon Steel Corporation
    Inventors: Kouichi Uchino, Toshiya Kuroki, Masaharu Ueda
  • Patent number: 5538566
    Abstract: High strength steel parts and method of making are disclosed by providing a blank of high-strength steel material having a tensile strength of at least about 120,000 psi and a yield strength of at least about 90,000 psi and warm forming the blank to provide the part of desired geometric configuration while substantially maintaining or increasing the strength properties of the blank.
    Type: Grant
    Filed: July 5, 1995
    Date of Patent: July 23, 1996
    Assignee: Consolidated Metal Products, Inc.
    Inventor: Hugh M. Gallagher, Jr.
  • Patent number: 5482576
    Abstract: A railway-track element is disclosed not only for normal track but also for rail points. The track element is formed of vacuum-treated steel containing at least 0.53 to 0.62% C, 0.65 to 1.1% Mn, 0.8 to 1.3% Cr, 0.05 to 0.11% Mo, 0.05 to 0.11% V and .ltoreq.0.02% P, the balance being iron plus the usual production-related impurities. The track element is in the form of a rail made of rolled pearlitic steel. If the track element is to be used for points, the starting material is a length of rolled rail with a martensitic structure produced by heat treatment at least in the rail head area.
    Type: Grant
    Filed: July 8, 1994
    Date of Patent: January 9, 1996
    Assignee: BWG Butzbacher Weichenbau, GmbH
    Inventors: Wilhelm Heller, Gerhard Ratz
  • Patent number: 5382307
    Abstract: A process for manufacturing high-strength bainitic steel rails with an excellent rolling-contact fatigue resistance comprising the steps of hot rolling steel containing 0.15% to 0.45% carbon, 0.15% to 2.00% silicon, 0.30% to 2.00% manganese, 0.50% to 3.00% chromium, and at least one element selected from a group of molybdenum, nickel, copper, niobium, vanadium, titanium and boron, subjecting the hot-rolled rail to an accelerated cooling from the austenite region to a temperature between 500.degree. to 300.degree. C., at which the accelerated cooling is stopped, at a rate of 1.degree. to 10.degree. C. per second, and then further cooling the rail to a lower temperature by natural or controlled cooling. The obtained rail exhibits a hardness of Hv 300 to 400 in the center of the rail head surface of the head and not lower than Hv 350 in the gage corner, and the hardness of the gage corner is higher than that of the center of the rail head surface by Hv 30 or more.
    Type: Grant
    Filed: February 24, 1994
    Date of Patent: January 17, 1995
    Assignee: Nippon Steel Corporation
    Inventors: Hideaki Kageyama, Masaharu Ueda, Kazuo Sugino
  • Patent number: 5328531
    Abstract: Process for the manufacture of components from untreated steel, comprising a series of heat treatment and forming operations, characterised by heating the steel to a temperature above the transition point (austenizing), isothermal quenching in a fluidized bed bath immediately after the austenizing heating giving the steel a bainitic structure and then forming the components under mild conditions.
    Type: Grant
    Filed: December 1, 1992
    Date of Patent: July 12, 1994
    Inventor: Jacques Gautier
  • Patent number: 5250126
    Abstract: A method for manufacturing a rail for use in a linear motion rolling contact guide unit is provided. A rail intermediate product having a top surface, a pair of side surfaces, each formed with a guide groove portion, and a bottom surface is provided by drawing from an alloy steel material. Then the guide groove portion is hardened by induction hardening. The side surface is then ground by a profiled grinder having a grinding shape complementary to the shape of a side surface of a finished rail.
    Type: Grant
    Filed: June 17, 1992
    Date of Patent: October 5, 1993
    Assignee: Nippon Thompson Co., Ltd.
    Inventors: Yasumasa Ohya, Koji Kano
  • Patent number: RE41033
    Abstract: This invention is directed to improve a wear resistance and a damage resistance required for a rail of a sharply curved zone of a heavy load railway, comprising more than 0.85 to 1.20% of C, 0.10 to 1.00% of Si, 0.40 to 1.50% of Mn and if necessary, at least one member selected from the group consisting of Cr, Mo, V, Nb, Co and B, and retaining high temperature of hot rolling or a steel rail heated to a high temperature for the purpose of heat-treatment, the present invention provides a pearlitic steel rail having a good wear resistance and a good damage resistance, and a method of producing the same, wherein a head portion of the steel rail is acceleratedly cooled at a rate of 1° to 10° C./sec from an austenite zone temperature to a cooling stop temperature of 700° to 500° C. so that the hardness of the head portion is at least Hv 320 within the range of a 20 mm depth.
    Type: Grant
    Filed: November 13, 1995
    Date of Patent: December 8, 2009
    Assignee: Nippn Steel Corporation
    Inventors: Masaharu Ueda, Hideaki Kageyama, Kouichi Uchino, Koji Babazono, Ken Kutaragi
  • Patent number: RE35106
    Abstract: A method for manufacturing a rail for use in a linear motion rolling contact guide unit is provided. A rail intermediate product having a top surface, a pair of side surfaces, each formed with a guide groove portion, and a bottom surface is provided by drawing from an alloy steel material. Then the guide groove portion is hardened by induction hardening. The side surface is then ground by a profiled grinder having a grinding shape complementary to the shape of a side surface of a finished rail.
    Type: Grant
    Filed: August 11, 1994
    Date of Patent: December 5, 1995
    Assignee: Nippon Thompson Co., Ltd.
    Inventors: Yasumasa Ohya, Koji Kano
  • Patent number: RE42360
    Abstract: This invention is directed to improve a wear resistance and a damage resistance required for a rail of a sharply curved zone of a heavy load railway, comprising more than 0.85 to 1.20% of C, 0.10 to 1.00% of Si, 0.40 to 1.50% of Mn and if necessary, at least one member selected from the group consisting of Cr, Mo, V, Nb, Co and B, and retaining high temperature of hot rolling or a steel rail heated to a high temperature for the purpose of heat-treatment, the present invention provides a pearlitic steel rail having a good wear resistance and a good damage resistance, and a method of producing the same, wherein a head portion of the steel rail is acceleratedly cooled at a rate of 1° to 10° C./sec from an austenite zone temperature to a cooling stop temperature of 700° to 500° C. so that the hardness of the head portion is at least Hv 320 within the range of a 20 mm depth.
    Type: Grant
    Filed: November 13, 1995
    Date of Patent: May 17, 2011
    Assignee: Nippon Steel Corporation
    Inventors: Masaharu Ueda, Hideaki Kageyama, Kouichi Uchino, Koji Babazono, Ken Kutaragi
  • Patent number: RE42668
    Abstract: This invention is directed to improve a wear resistance and a damage resistance required for a rail of a sharply curved zone of a heavy load railway, comprising more than 0.85 to 1.20% of C, 0.10 to 1.00% of Si, 0.40 to 1.50% of Mn and if necessary, at least one member selected from the group consisting of Cr, Mo, V, Nb, Co and B, and retaining high temperature of hot rolling or a steel rail heated to a high temperature for the purpose of heat-treatment, the present invention provides a pearlitic steel rail having a good wear resistance and a good damage resistance, and a method of producing the same, wherein a head portion of the steel rail is acceleratedly cooled at a rate of 1° to 10° C./sec from an austenite zone temperature to a cooling stop temperature of 700° to 500° C. so that the hardness of the head portion is at least Hv 320 within the range of a 20 mm depth.
    Type: Grant
    Filed: November 13, 1995
    Date of Patent: September 6, 2011
    Assignee: Nippon Steel Corporation
    Inventors: Masaharu Ueda, Hideaki Kageyama, Kouichi Uchino, Koji Babazono, Ken Kutaragi