Patents by Inventor Yuji Arai

Yuji Arai has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20210231078
    Abstract: Provided is an ignition control section and an injection control section. When partial compression ignition combustion is carried out, the ignition control section causes an ignition plug to carry out: main ignition in which a spark is generated in a late period of a compression stroke or an initial period of an expansion stroke to initiate SI combustion; and preceding ignition in which the spark is generated at earlier timing than the main ignition. Also, when the partial compression ignition combustion is carried out, the injection control section causes an injector to inject fuel at such timing that the fuel exists in a cylinder at an earlier time point than the preceding ignition. Ignition timing of the preceding ignition is set to be more retarded when an in-cylinder pressure specified by an in-cylinder pressure specification section is high than when the in-cylinder pressure is low.
    Type: Application
    Filed: April 17, 2019
    Publication date: July 29, 2021
    Inventors: Kota MATSUMOTO, Tomonori URUSHIHARA, Keiji MARUYAMA, Masanari SUEOKA, Ryohei ONO, Yuji HARADA, Toru MIYAMOTO, Atsushi INOUE, Tatsuhiro TOKUNAGA, Takuya OHURA, Yusuke KAWAI, Tomohiro NISHIDA, Keita ARAI, Yodai YAMAGUCHI
  • Publication number: 20210231077
    Abstract: An engine apparatus includes an ignition control section and an injection control section. When the partial compression ignition combustion is carried out, the ignition control section causes an ignition plug to carry out: main ignition in which a spark is generated in a late period of a compression stroke or an initial period of an expansion stroke to initiate the SI combustion; and preceding ignition in which the spark is generated at earlier timing than the main ignition. Also, when the partial compression ignition combustion is carried out, the injection control section causes the injector to inject fuel at such timing that the fuel exists in a cylinder at an earlier time point than the preceding ignition. Energy of the preceding ignition is set to be lower when a swirl flow is gentle than when the swirl flow is intense.
    Type: Application
    Filed: April 23, 2019
    Publication date: July 29, 2021
    Inventors: Kota MATSUMOTO, Tomonori URUSHIHARA, Keiji MARUYAMA, Masanari SUEOKA, Ryohei ONO, Yuji HARADA, Toru MIYAMOTO, Atsushi INOUE, Tatsuhiro TOKUNAGA, Takuya OHURA, Yusuke KAWAI, Tomohiro NISHIDA, Keita ARAI, Yodai YAMAGUCHI
  • Publication number: 20210231076
    Abstract: A control apparatus for a compression-ignition type engine is applied to an engine capable of carrying out partial compression ignition combustion. When the partial compression ignition combustion is carried out, an ignition control section of the control apparatus causes an ignition plug to carry out: main ignition in which a spark is generated to initiate the SI combustion; and preceding ignition in which the spark is generated at an earlier time point than the main ignition. An injection control section causes the ignition plug to inject fuel in an intake stroke. The ignition control section sets energy of the preceding ignition to be lower than energy of the main ignition and causes the ignition plug to carry out the preceding ignition after the fuel injection in the intake stroke or an early period or a middle period of a compression stroke.
    Type: Application
    Filed: April 19, 2019
    Publication date: July 29, 2021
    Inventors: Kota MATSUMOTO, Tomonori URUSHIHARA, Keiji MARUYAMA, Masanari SUEOKA, Ryohei ONO, Yuji HARADA, Toru MIYAMOTO, Atsushi INOUE, Tatsuhiro TOKUNAGA, Takuya OHURA, Yusuke KAWAI, Tomohiro NISHIDA, Keita ARAI, Yodai YAMAGUCHI
  • Publication number: 20210222610
    Abstract: The invention is provided with an ignition control section and an injection control section. When partial compression ignition combustion is carried out, the ignition control section causes an ignition plug to carry out: main ignition in which a spark is generated in a late period of a compression stroke or an initial period of an expansion stroke to initiate SI combustion; and preceding ignition in which the spark is generated at earlier timing than the main ignition. Also, when the partial compression ignition combustion is carried out, the injection control section causes an injector to inject fuel at such timing that the fuel exists in a cylinder at an earlier time point than the preceding ignition. Timing of the preceding ignition is set to be more retarded when an engine speed is high than when the engine speed is low.
    Type: Application
    Filed: April 17, 2019
    Publication date: July 22, 2021
    Inventors: Kota MATSUMOTO, Tomonori URUSHIHARA, Keiji MARUYAMA, Masanari SUEOKA, Ryohei ONO, Yuji HARADA, Toru MIYAMOTO, Atsushi INOUE, Tatsuhiro TOKUNAGA, Takuya OHURA, Yusuke KAWAI, Tomohiro NISHIDA, Keita ARAI, Yodai YAMAGUCHI
  • Publication number: 20210222642
    Abstract: An engine control apparatus includes an ignition control section and an injection control section. When the partial compression ignition combustion is carried out, the ignition control section causes an ignition plug to carry out: main ignition in which a spark is generated in a late period of a compression stroke or an initial period of a expansion stroke to initiate the SI combustion; and preceding ignition in which the spark is generated at earlier timing than the main ignition. Also, when the partial compression ignition combustion is carried out, the injection control section causes the injector to inject fuel at such timing that the fuel exists in a cylinder at an earlier time point than the preceding ignition. The energy of the preceding ignition is set to be higher when fuel concentration specified by a fuel concentration specification section is low than when the fuel concentration is high.
    Type: Application
    Filed: April 23, 2019
    Publication date: July 22, 2021
    Inventors: Kota MATSUMOTO, Tomonori URUSHIHARA, Keiji MARUYAMA, Masanari SUEOKA, Ryohei ONO, Yuji HARADA, Toru MIYAMOTO, Atsushi INOUE, Tatsuhiro TOKUNAGA, Takuya OHURA, Yusuke KAWAI, Tomohiro NISHIDA, Keita ARAI, Yodai YAMAGUCHI
  • Patent number: 11060160
    Abstract: A low-alloy steel has a composition including, by mass %, C: more than 0.45 and up to 0.65%; Si: 0.05 to 0.50%; Mn: 0.10 to 1.00%; P: up to 0.020%; S: up to 0.0020%; Cu: up to 0.1%; Cr: 0.40 to 1.50%; Ni: up to 0.1%; Mo: 0.50 to 2.50%; Ti: up to 0.01%; V: 0.05 to 0.25%; Nb: 0.005 to 0.20%; Al: 0.010 to 0.100%; B: up to 0.0005%; Ca: 0 to 0.003%; 0: up to 0.01%; N: up to 0.007%; and other elements. A microstructure consists of tempered martensite and retained austenite <2% in volume fraction, crystal grain size number being 9.0 or larger, number density of carbonitride-based inclusions with grain diameter of 50 ?m or larger being 10 inclusions/100 mm2 or smaller, and yield strength being 965 MPa or higher.
    Type: Grant
    Filed: December 4, 2015
    Date of Patent: July 13, 2021
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Keiichi Kondo, Yuji Arai, Takanori Sato
  • Publication number: 20210198775
    Abstract: The steel material according to the present disclosure contains a chemical composition consisting of, in mass %, C: 0.20 to 0.50%, Si: 0.05 to 0.50%, Mn: 0.05 to 1.00%, P: 0.030% or less, S: less than 0.0050%, Al: 0.005 to 0.050%, Cr: 0.10 to 1.50%, Mo: 0.25 to 1.80%, Ti: 0.002 to 0.050%, Nb: 0.002 to 0.100%, B: 0.0001 to 0.0050%, N: 0.0070% or less and O: less than 0.0050% with the balance being Fe and impurities. A yield strength is within a range of 655 to 1069 MPa, and a yield ratio is 85% or more. A proportion of KAM values of 1° or less is 30 area % or more.
    Type: Application
    Filed: March 22, 2019
    Publication date: July 1, 2021
    Inventors: Hiroki KAMITANI, Atsushi SOMA, Keiichi KONDO, Shinji YOSHIDA, Yuji ARAI
  • Publication number: 20210180149
    Abstract: The steel pipe according to the present disclosure contains a chemical composition consisting of, in mass %, C: 0.25 to 0.50%, Si: 0.05 to 0.50%, Mn: 0.05 to 1.00%, P: 0.025% or less, S: 0.0050% or less, Al: 0.005 to 0.100%, Cr: 0.30 to 1.50%, Mo: 0.25 to 3.00%, Ti: 0.002 to 0.050%, N: 0.0010 to 0.0100% and O: 0.0030% or less, with the balance being Fe and impurities. The steel pipe contains an amount of dissolved C within a range of 0.010 to 0.050 mass %. The tensile yield strength in the axial direction and the circumferential direction is 862 to 965 MPa, and the yield ratio in the axial direction is 90% or more. The tensile yield strength in the circumferential direction is 30 to 80 MPa higher than the compressive yield strength in the circumferential direction.
    Type: Application
    Filed: March 22, 2019
    Publication date: June 17, 2021
    Inventors: Yuji ARAI, Shinji YOSHIDA, Atsushi SOMA, Hiroki KAMITANI
  • Patent number: 10988819
    Abstract: A high-strength steel material that has a chemical composition containing, by mass %, C: 0.30 to 1.0%, Si: 0.05 to 1.0%, Mn: 16.0 to 35.0%, P: 0.030% or less, S: 0.030% or less, Al: 0.003 to 0.06%, N: 0.1% or less, V: 0 to 3.0%, Ti: 0 to 1.5%, Nb: 0 to 1.5%, Cr: 0 to 5.0%, Mo: 0 to 3.0%, Cu: 0 to 1.0%, Ni: 0 to 1.0%, B: 0 to 0.02%, Zr: 0 to 0.5%, Ta: 0 to 0.5%, Ca: 0 to 0.005%, Mg: 0 to 0.005%, and the balance: Fe and impurities, and that satisfies [V+Ti+Nb>2.0], in which: a number density of carbides/carbo-nitrides having a circle-equivalent diameter of 5 to 30 nm precipitating in the steel is 50 to 700/?m2, and a number density of carbides/carbo-nitrides having a circle-equivalent diameter of more than 100 nm precipitating in the steel is less than 10/?m2; a yield stress is 758 MPa or more; and a KISSC value obtained in a DCB test is 33.7 MPa·m0.5 or more.
    Type: Grant
    Filed: March 15, 2017
    Date of Patent: April 27, 2021
    Assignee: Nippon Steel Corporation
    Inventors: Shinji Yoshida, Yuji Arai
  • Publication number: 20210047714
    Abstract: The steel material according to the present disclosure contains a chemical composition consisting of, in mass %, C: more than 0.50 to 0.80%, Si: 0.05 to 1.00%, Mn: 0.05 to 1.00%, P: 0.025% or less, S: 0.0100% or less, Al: 0.005 to 0.100%, Cr: 0.20 to 1.50%, Mo: 0.25 to 1.50%, Ti: 0.002 to 0.050%, B: 0.0001 to 0.0050%, N: 0.0100% or less and O: 0.0100% or less, with the balance being Fe and impurities. The steel material contains an amount of dissolved C within a range of 0.010 to 0.060 mass %. The steel material also has a yield strength within a range of 862 to less than 965 MPa, and a yield ratio of the steel material is 90% or more.
    Type: Application
    Filed: March 22, 2019
    Publication date: February 18, 2021
    Inventors: Shinji YOSHIDA, Yuji ARAI, Atsushi SOMA, Hiroki KAMITANI
  • Publication number: 20210032734
    Abstract: The steel pipe according to the present disclosure contains a chemical composition consisting of, in mass %, C: more than 0.50 to 0.65%, Si: 0.05 to 0.50%, Mn: 0.05 to 1.00%, P: 0.025% or less, S: 0.0050% or less, Al: 0.005 to 0.100%, Cr: 0.30 to 1.50%, Mo: 0.25 to 3.00%, Ti: 0.002 to 0.050%, N: 0.0010 to 0.0100% and O: 0.0030% or less, with the balance being Fe and impurities. The steel pipe contains an amount of dissolved C within a range of 0.010 to 0.060 mass %. The tensile yield strength in the axial direction and the circumferential direction is 862 to 1069 MPa, and the yield ratio in the axial direction is 90% or more. The tensile yield strength in the circumferential direction is 30 to 80 MPa higher than the compressive yield strength in the circumferential direction.
    Type: Application
    Filed: March 22, 2019
    Publication date: February 4, 2021
    Inventors: Yuji ARAI, Shinji YOSHIDA, Atsushi SOMA, Hiroki KAMITANI
  • Publication number: 20210025021
    Abstract: A seamless steel pipe heat-treatment-finishing-treatment continuous facility includes: a heat treatment apparatus; a steel pipe inspection apparatus which performs a test for a surface defect and/or an inner defect of the seamless steel pipe, the steel pipe inspection apparatus being disposed downstream of the heat treatment apparatus; a main transfer mechanism which forms a main transfer path MT for transferring the seamless steel pipe, discharged from the heat treatment apparatus, to the steel pipe inspection apparatus disposed downstream of the heat treatment apparatus; and a first forced steel pipe-temperature reduction apparatus which forcibly reduces a temperature of the seamless steel pipe on the main transfer path MT, the first forced steel pipe-temperature reduction apparatus being disposed on the main transfer path MT at a position downstream of the heat treatment apparatus and upstream of the steel pipe inspection apparatus.
    Type: Application
    Filed: March 26, 2019
    Publication date: January 28, 2021
    Inventors: Hiroki KAMITANI, Takanori TANAKA, Atsushi SOMA, Keiichi KONDO, Hideki MITSUNARI, Seiya OKADA, Takuya MATSUMOTO, Shinji YOSHIDA, Yuji ARAI
  • Publication number: 20210017635
    Abstract: The steel material according to the present disclosure contains a chemical composition consisting of, in mass %, C: 0.20 to 0.50%, Si: 0.05 to 0.50%, Mn: 0.05 to 1.00%, P: 0.030% or less, S: 0.0100% or less, Al: 0.005 to 0.100%, Cr: 0.10 to 1.50%, Mo: 0.25 to 1.50%, Ti: 0.002 to 0.050%, N: 0.0100% or less and O: 0.0100% or less, with the balance being Fe and impurities. The steel material contains an amount of dissolved C within a range of 0.010 to 0.050 mass %. The steel material also has a yield strength within a range of 655 to less than 862 MPa, and a yield ratio of the steel material is 85% or more.
    Type: Application
    Filed: March 25, 2019
    Publication date: January 21, 2021
    Inventors: Hiroki KAMITANI, Atsushi SOMA, Shinji YOSHIDA, Yuji ARAI, Seiya OKADA
  • Publication number: 20210010099
    Abstract: The steel material according to the present disclosure contains a chemical composition consisting of, in mass %, C: 0.20 to 0.50%, Si: 0.05 to 1.00%, Mn: 0.05 to 1.00%, P: 0.025% or less, S: 0.0100% or less, Al: 0.005 to 0.100%, Cr: 0.20 to 1.50%, Mo: 0.25 to 1.50%, Ti: 0.002 to 0.050%, B: 0.0001 to 0.0050%, N: 0.0100% or less and O: 0.0100% or less, with the balance being Fe and impurities. The steel material contains an amount of dissolved C within a range of 0.010 to 0.050 mass %. The steel material also has a yield strength within a range of 965 to 1069 MPa, and a yield ratio of the steel material is 90% or more.
    Type: Application
    Filed: March 22, 2019
    Publication date: January 14, 2021
    Inventors: Shinji YOSHIDA, Yuji ARAI, Atsushi SOMA, Hiroki KAMITANI
  • Publication number: 20200384514
    Abstract: The production method of a seamless steel pipe includes a heating step of heating an Nb-containing steel material to 800 to 1030° C., a pipe-making step of producing a hollow shell by performing piercing-rolling or elongation-rolling on the Nb-containing steel material, by using a piercing mill including a plurality of skewed rolls, a plug disposed between the plurality of skewed rolls, and a mandrel bar, and a cooling step immediately after rolling, of carrying out cooling using a cooling liquid on a hollow shell portion that passes between rear ends of the plurality of skewed rolls, in the hollow shell, so as to reduce an outer surface temperature of the hollow shell portion to 700 to 1000° C. within 15.0 seconds after the hollow shell portion passes between the rear ends of the plurality of skewed rolls.
    Type: Application
    Filed: November 28, 2018
    Publication date: December 10, 2020
    Inventors: Kouji YAMANE, Kazuhiro SHIMODA, Yuji ARAI, Akihiro SAKAMOTO, Yasuhiko DAIMON, Haruka OBE
  • Patent number: 10752979
    Abstract: Provided is a low alloy oil-well steel pipe having a yield strength of 793 MPa or more, and an excellent SSC resistance. A low alloy oil-well steel pipe according to the present invention includes a chemical composition consisting of: in mass %, C: 0.25 to 0.35%; Si: 0.05 to 0.50%; Mn: 0.10 to 1.50%; Cr: 0.40 to 1.50%; Mo: 0.40 to 2.00%; V: 0.05 to 0.25%; Nb: 0.010 to 0.040%; Ti: 0.002 to 0.050%; sol. Al: 0.005 to 0.10%; N: 0.007% or less; B: 0.0001 to 0.0035%; and Ca: 0 to 0.005%; and a balance being Fe and impurities. In a microstructure of the low alloy oil-well steel pipe, a number of cementite particles each of which has an equivalent circle diameter of 200 nm or more is 100 particles/100 ?m2 or more. The above low alloy oil-well steel pipe has a yield strength of 793 MPa or more.
    Type: Grant
    Filed: October 2, 2015
    Date of Patent: August 25, 2020
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Keiichi Kondo, Yuji Arai
  • Patent number: 10655200
    Abstract: The steel material according to the present invention contains, in mass %, C: 0.15 to 0.45%, Si: 0.10 to 1.0%, Mn: 0.10 to 0.8%, P: 0.050% or less, S: 0.010% or less, Al: 0.01 to 0.1%, N: 0.010% or less, Cr: 0.1 to 2.5%, Mo: 0.35 to 3.0%, Co: 0.05 to 2.0%, Ti: 0.003 to 0.040%, Nb: 0.003 to 0.050%, Cu: 0.01 to 0.50%, and Ni: 0.01 to 0.50%, and satisfies the following Formulae. A prior-austenite grain diameter of its microstructure is less than 5 ?m, and a block diameter of its microstructure is less than 2 ?m. The microstructure contains a total of 90% by volume or more of tempered martensite and tempered bainite. C+Mn/6+(Cr+Mo+V)/5+(Cu+Ni)/15?Co/6+??0.70??(1) (3C+Mo+3Co)/(3Mn+Cr)?1.0??(2).
    Type: Grant
    Filed: August 30, 2017
    Date of Patent: May 19, 2020
    Assignee: Nippon Steel Corporation
    Inventors: Yuji Arai, Kengo Hata
  • Publication number: 20200123624
    Abstract: A high-strength steel material that has a chemical composition containing, by mass %, C: 0.30 to 1.0%, Si: 0.05 to 1.0%, Mn: 16.0 to 35.0%, P: 0.030% or less, S: 0.030% or less, Al: 0.003 to 0.06%, N: 0.1% or less, V: 0 to 3.0%, Ti: 0 to 1.5%, Nb: 0 to 1.5%, Cr: 0 to 5.0%, Mo: 0 to 3.0%, Cu: 0 to 1.0%, Ni: 0 to 1.0%, B: 0 to 0.02%, Zr: 0 to 0.5%, Ta: 0 to 0.5%, Ca: 0 to 0.005%, Mg: 0 to 0.005%, and the balance: Fe and impurities, and that satisfies [V+Ti+Nb>2.0], in which: a number density of carbides/carbo-nitrides having a circle-equivalent diameter of 5 to 30 nm precipitating in the steel is 50 to 700/?m2, and a number density of carbides/carbo-nitrides having a circle-equivalent diameter of more than 100 nm precipitating in the steel is less than 10/?m2; a yield stress is 758 MPa or more; and a KISSC value obtained in a DCB test is 33.7 MPa·m0.5 or more.
    Type: Application
    Filed: March 15, 2017
    Publication date: April 23, 2020
    Inventors: Shinji Yoshida, Yuji Arai
  • Patent number: 10563793
    Abstract: Provided is a low alloy oil-well steel pipe having a yield strength of 827 MPa or more, and an excellent SSC resistance. The low alloy oil-well steel pipe according to the present invention consisting of: in mass %, C: more than 0.35 to 0.65%; Si: 0.05 to 0.50%; Mn: 0.10 to 1.00%; Cr: 0.40 to 1.50%; Mo: 0.50 to 2.00%; V: 0.05 to 0.25%; Nb: 0.01 to 0.040%; sol.Al: 0.005 to 0.10%; N: 0.007% or less; Ti: 0 to 0.012%; Ca: 0 to 0.005%; and a balance being Fe and impurities, the impurities including: P: 0.020% or less; S: 0.002% or less; O: 0.006% or less; Ni: 0.10% or less; Cu: 0.03% or less; and B: 0.0005% or less, wherein in a microstructure, a number of cementite particles each of which has an equivalent circle diameter of 200 nm or more is 200 particles/100 ?m2 or more, and a yield strength is 827 MPa or more.
    Type: Grant
    Filed: July 21, 2015
    Date of Patent: February 18, 2020
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Keiichi Kondo, Yuji Arai
  • Publication number: 20200040436
    Abstract: The steel material according to the present invention contains a chemical composition consisting of, in mass %, C: 0.25 to 0.50%, Si: 0.05 to 0.50%, Mn: 0.05 to 1.00%, P: 0.025% or less, S: 0.0100% or less, Al: 0.005 to 0.100%, Cr: 0.30 to 1.50%, Mo: 0.25 to 1.50%, Ti: 0.002 to 0.050%, B: 0.0001 to 0.0050%, N: 0.002 to 0.010% and O: 0.0100% or less, with the balance being Fe and impurities. The steel material also contains an amount of dissolved C within a range of 0.010 to 0.050 mass %. The steel material also contains an yield strength is in a range of 862 to less than 965 MPa, and an yield ratio is 90% or more.
    Type: Application
    Filed: October 6, 2017
    Publication date: February 6, 2020
    Inventors: Yuji Arai, Shinji Yoshida, Atsushi Soma, Hiroki Kamitani