Patents by Inventor Keisuke Hitoshio
Keisuke Hitoshio 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).
-
Patent number: 9175360Abstract: There is provided a method for manufacturing a seamless steel pipe for line pipe, capable of improving the toughness of the seamless steel pipe for line pipe. A round billet having a chemical composition, by mass percent, of C: 0.02 to 0.15%, Si: at most 0.5%, and Mn: 0.5 to 2.5%, the balance being Fe and impurities, is heated. The heated round billet is piercing-rolled to produce a hollow shell. The hollow shell is elongated and rolled and sized to produce a seamless steel pipe. The seamless steel pipe is water cooled, and the water cooling is stopped when the temperature of the seamless steel pipe reaches at most 450° C. The water-cooled seamless steel pipe is quenched, and the quenched seamless steel pipe is tempered.Type: GrantFiled: July 2, 2012Date of Patent: November 3, 2015Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATIONInventors: Keisuke Hitoshio, Kunio Kondo, Yuji Arai
-
Patent number: 8709174Abstract: A seamless steel pipe for line pipe having high strength and high toughness contains, by mass percent, C: 0.02 to 0.10%, Si: at most 0.5%, Mn: 0.5 to 2.0%, Al: 0.01 to 0.1%, P: at most 0.03%, S: at most 0.005%, Ca: at most 0.005%, and N: at most 0.007%, and further contains at least one selected from a group consisting of Ti: at most 0.008%, V: less than 0.06%, and Nb: at most 0.05%, the balance being Fe and impurities. A carbon equivalent Ceq defined by Formula (1) is at least 0.38, a content of Ti, V and Nb satisfies Formula (2), and the size of carbo-nitride containing at least one of Ti, V, Nb and Al is at most 200 nm, Ceq=C+Mn/6+(Cr+Mo+V)/5+(Ni+Cu)/15??(1) Ti+V+Nb<0.06??(2).Type: GrantFiled: September 11, 2012Date of Patent: April 29, 2014Assignee: Nippon Steel & Sumitomo Metal CorporationInventors: Yuji Arai, Keisuke Hitoshio
-
Publication number: 20130000790Abstract: A seamless steel pipe for line pipe having high strength and high toughness contains, by mass percent, C: 0.02 to 0.10%, Si: at most 0.5%, Mn: 0.5 to 2.0%, Al: 0.01 to 0.1%, P: at most 0.03%, S: at most 0.005%, Ca: at most 0.005%, and N: at most 0.007%, and further contains at least one selected from a group consisting of Ti: at most 0.008%, V: less than 0.06%, and Nb: at most 0.05%, the balance being Fe and impurities. A carbon equivalent Ceq defined by Formula (1) is at least 0.38, a content of Ti, V and Nb satisfies Formula (2), and the size of carbo-nitride containing at least one of Ti, V, Nb and Al is at most 200 nm, Ceq=C+Mn/6+(Cr+Mo+V)/5+(Ni+Cu)/15??(1) Ti+V+Nb<0.06??(2).Type: ApplicationFiled: September 11, 2012Publication date: January 3, 2013Applicant: SUMITOMO METAL INDUSTRIES, LTD.Inventors: Yuji ARAI, Keisuke Hitoshio
-
Publication number: 20120267014Abstract: There is provided a method for manufacturing a seamless steel pipe for line pipe, capable of improving the toughness of the seamless steel pipe for line pipe. A round billet having a chemical composition, by mass percent, of C: 0.02 to 0.15%, Si: at most 0.5%, and Mn: 0.5 to 2.5%, the balance being Fe and impurities, is heated. The heated round billet is piercing-rolled to produce a hollow shell. The hollow shell is elongated and rolled and sized to produce a seamless steel pipe. The seamless steel pipe is water cooled, and the water cooling is stopped when the temperature of the seamless steel pipe reaches at most 450° C. The water-cooled seamless steel pipe is quenched, and the quenched seamless steel pipe is tempered.Type: ApplicationFiled: July 2, 2012Publication date: October 25, 2012Applicant: Sumitomo Metal Industries, Ltd.Inventors: Keisuke Hitoshio, Kunio Kondo, Yuji Arai
-
Patent number: 8147623Abstract: To provide a steel pipe as a fuel injection pipe with high material strength, high internal pressure limit free from fatigue failure, prolonged fatigue life, and high reliability. A steel pipe as a fuel injection pipe of 500 N/mm2 or higher tensile strength comprising, by mass, C: 0.12 to 0.27%, Si: 0.05 to 0.40%, and Mn: 0.8 to 2.0%, and the balance being Fe and impurities, the contents of Ca, P, and S in the impurities being Ca: 0.001% or less, P: 0.02% or less, and S: 0.01% or less, respectively, characterized in that the maximum diameter of nonmetallic inclusions present in at least in a region extending from the inner surface of the steel pipe to a depth of 20 ?m is 20 ?m or less. Further, this steel pipe may contain, in place of a portion of Fe, at least one selected from among Cr: 1% or less, Mo: 1% or less, Ti: 0.04% or less, Nb: 0.04% or less, and V: 0.1% or less.Type: GrantFiled: October 2, 2008Date of Patent: April 3, 2012Assignee: Sumitomo Metal Industries, Ltd.Inventors: Kikuo Asada, Osamu Endo, Katsunori Nagao, Keisuke Hitoshio
-
Patent number: 7846274Abstract: In order to manufacture a steel pipe for an air bag which can cope with increase in the pressure of gas blown into an air bag and decreases in the wall thickness of an accumulator, a steel having a composition, mass %, of: C: 0.05-0.20%, Si: 0.1-1.0%, Mn: 0.20-2.0%, P: at most 0.025%, S: at most 0.010%, Cr: 0.05-1.0%, Al: at most 0.10%, if necessary at least one of Mo: at most 0.50%, Ni: at most 1.5%, Cu: at most 0.5%, V: at most 0.2%, Ti: at most 0.1%, Nb: at most 0.1%, and B: at most 0.005%, and also if necessary, at least one of Ca: at most 0.01%, Mg: at most 0.01%, and REM (rare earth elements): at most 0.01%, and a remainder of Fe and impurities is used to produce a steel pipe, and the pipe is then subjected to cold working to predetermined dimensions, then to heating to a temperature of at least the Ac1 transformation temperature followed by quenching, and then to tempering at a temperature no higher than the Ac1 transformation temperature.Type: GrantFiled: September 24, 2004Date of Patent: December 7, 2010Assignee: Sumitomo Metal Industries, Ltd.Inventors: Kunio Kondo, Miyuki Yamamoto, Takashi Takano, Kenichi Beppu, Susumu Hirano, Keisuke Hitoshio, Hidetoshi Kurata
-
Patent number: 7566416Abstract: A steel pipe for an airbag inflator having a high strength of at least 900 MPa and preferably at least 1000 MPa in tensile strength along with a high toughness and exhibiting good resistance to bursting such that it has no propagation of cracks in a burst test at ?40° C. or below is manufactured by quenching a pipe of a steel comprising, in mass %, C: 0.05-0.20 %, Si: 0.1-1.0 %, P: at most 0.025 %, S: at most 0.010 %, Cr: 0.05-1.45 %, Al: at most 0.10 %, and one or both of Ti and Mn satisfying Ti?0.02% and 0.4%?Mn+40Ti?1.2% from a temperature of at least the Ac1 transformation point of the steel, tempering the pipe at a temperature lower than the Ac1 transformation point, applying cold working to it with a reduction of area of at most 65%, and subjecting it to stress relief annealing at a temperature lower than the Ac1 transformation point.Type: GrantFiled: October 28, 2005Date of Patent: July 28, 2009Assignee: Sumitomo Metal Industries, Ltd.Inventors: Takashi Takano, Yuji Arai, Kunio Kondo, Keisuke Hitoshio
-
Publication number: 20090078341Abstract: To provide a steel pipe as a fuel injection pipe with high material strength, high internal pressure limit free from fatigue failure, prolonged fatigue life, and high reliability. A steel pipe as a fuel injection pipe of 500 N/mm2 or higher tensile strength comprising, by mass, C: 0.12 to 0.27%, Si: 0.05 to 0.40%, and Mn: 0.8 to 2.0%, and the balance being Fe and impurities, the contents of Ca, P, and S in the impurities being Ca: 0.001% or less, P: 0.02% or less, and S: 0.01% or less, respectively, characterized in that the maximum diameter of nonmetallic inclusions present in at least in a region extending from the inner surface of the steel pipe to a depth of 20 ?m is 20 ?m or less. Further, this steel pipe may contain, in place of a portion of Fe, at least one selected from among Cr: 1% or less, Mo: 1% or less, Ti: 0.04% or less, Nb: 0.04% or less, and V: 0.1% or less.Type: ApplicationFiled: October 2, 2008Publication date: March 26, 2009Applicants: USUI KOKUSAI SANGYO KAISHA, LTD., SUMITOMO METAL INDUSTRIES, LTD.Inventors: KIKUO ASADA, Osamu Endo, Katsunori Nagao, Keisuke Hitoshio
-
Publication number: 20060124211Abstract: A steel pipe for an airbag inflator having a high strength of at least 900 MPa and preferably at least 1000 MPa in tensile strength along with a high toughness and exhibiting good resistance to bursting such that it has no propagation of cracks in a burst test at ?40° C. or below is manufactured by quenching a pipe of a steel comprising, in mass %, C: 0.05-0.20 %, Si: 0.1-1.0 %, P: at most 0.025 %, S: at most 0.010 %, Cr: 0.05-1.45 %, Al: at most 0.10 %, and one or both of Ti and Mn satisfying Ti<0.02% and 0.4%?Mn+40Ti?1.2% from a temperature of at least the Ac1 transformation point of the steel, tempering the pipe at a temperature lower than the Ac1 transformation point, applying cold working to it with a reduction of area of at most 65%, and subjecting it to stress relief annealing at a temperature lower than the Ac1 transformation point.Type: ApplicationFiled: October 28, 2005Publication date: June 15, 2006Inventors: Takashi Takano, Yuji Arai, Kunio Kondo, Keisuke Hitoshio
-
Publication number: 20050266927Abstract: A steel tube hot-finished by the Mannesmann tube-making method is subjected to a simple grinding process for the inner surface, and thereafter to a cold drawing, so that the depth d of the concave portion in the concavo-convex profile forming the inner surface of the steel tube, the surface roughness Ra and the width w of the entrance in the concave portion are specified, or similarly the depth d of the concave portion in the concavo-convex profile, the Vickers hardness Hv of the inner surface layer and the width w of the entrance in the concave portion are specified, hollow parts for a drive shaft, which have an excellent fatigue strength and which is optimal to reduce the weight of a car body, can be produced. Accordingly, the application of the manufacturing method according to the present invention allows drive shafts for automobiles to be efficiently produced in a reduced manufacturing cost, thereby providing a significant advantage in the industry.Type: ApplicationFiled: July 29, 2005Publication date: December 1, 2005Inventors: Kouichi Kuroda, Tatsuya Okui, Keisuke Hitoshio
-
Patent number: 6878219Abstract: In order to manufacture a steel pipe for an air bag which can cope with increase in the pressure of gas blown into an air bag and decreases in the wall thickness of an accumulator, a steel having a composition, mass %, of: C: 0.05-0.20%, Si: 0.1-1.0%, Mn: 0.20-2.0%, P: at most 0.025%, S: at most 0.010%, Cr: 0.05-1.0%, Al: at most 0.10%, if necessary at least one of Mo: at most 0.50%, Ni: at most 1.5%, Cu: at most 0.5%, V: at most 0.2%, Ti: at most 0.1%, Nb: at most 0.1%, and B: at most 0.005%, and also if necessary, at least one of Ca: at most 0.01%, Mg: at most 0.01%, and REM (rare earth elements): at most 0.01%, and a remainder of Fe and impurities is used to produce a steel pipe, and the pipe is then subjected to cold working to predetermined dimensions, then to heating to a temperature of at least the Ac1 transformation temperature followed by quenching, and then to tempering at a temperature no higher than the Ac1 transformation temperature.Type: GrantFiled: November 27, 2002Date of Patent: April 12, 2005Assignee: Sumitomo Metal Industries, Ltd.Inventors: Kunio Kondo, Miyuki Yamamoto, Takashi Takano, Kenichi Beppu, Susumu Hirano, Keisuke Hitoshio, Hidetoshi Kurata
-
Publication number: 20050039826Abstract: In order to manufacture a steel pipe for an air bag which can cope with increase in the pressure of gas blown into an air bag and decreases in the wall thickness of an accumulator, a steel having a composition, mass %, of: C: 0.05-0.20%, Si: 0.1-1.0%, Mn: 0.20-2.0%, P: at most 0.025%, S: at most 0.010%, Cr: 0.05-1.0%, Al: at most 0.10%, if necessary at least one of Mo: at most 0.50%, Ni: at most 1.5%, Cu: at most 0.5%, V: at most 0.2%, Ti: at most 0.1%, Nb: at most 0.1%, and B: at most 0.005%, and also if necessary, at least one of Ca: at most 0.01%, Mg: at most 0.01%, and REM (rare earth elements): at most 0.01%, and a remainder of Fe and impurities is used to produce a steel pipe, and the pipe is then subjected to cold working to predetermined dimensions, then to heating to a temperature of at least the Ac1 transformation temperature followed by quenching, and then to tempering at a temperature no higher than the Ac1 transformation temperature.Type: ApplicationFiled: September 24, 2004Publication date: February 24, 2005Inventors: Kunio Kondo, Miyuki Yamamoto, Takashi Takano, Kenichi Beppu, Susumu Hirano, Keisuke Hitoshio, Hidetoshi Kurata
-
Publication number: 20030155052Abstract: In order to manufacture a steel pipe for an air bag which can cope with increase in the pressure of gas blown into an air bag and decreases in the wall thickness of an accumulator, a steel having a composition, mass %, of: 1 C: 0.05-0.20%, Si: 0.1-1.0%, Mn: 0.20-2.0%, P: at most 0.025%, S: at most 0.010%, Cr: 0.05-1.0%, Al: at most 0.Type: ApplicationFiled: November 27, 2002Publication date: August 21, 2003Inventors: Kunio Kondo, Miyuki Yamamoto, Takashi Takano, Kenichi Beppu, Susumu Hirano, Keisuke Hitoshio, Hidetoshi Kurata