Patents by Inventor Hirotsugu Kawanaka

Hirotsugu Kawanaka 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: 8901453
    Abstract: A laser processing system includes a laser processing head, a powder supply device, and a controller. The powder supply device supplies powder to the laser processing head. The laser processing head includes: a laser emission unit which irradiates a workpiece with laser light; and a powder supply unit which receives the powder supplied from a powder supply device to the laser processing head, and can supply the powder to a laser spot on the workpiece. The powder supply unit includes: a powder discharge unit which can discharge the powder toward the laser spot on the workpiece; and a powder-supply control mechanism which controls the amount of the powder to be supplied to the powder discharge unit, by distributing to the powder discharge unit at least a part of a flow of the powder supplied from the powder supply device. The controller controls the distributing by the powder-supply control mechanism.
    Type: Grant
    Filed: December 12, 2011
    Date of Patent: December 2, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Masanori Miyagi, Takeshi Tsukamoto, Hirotsugu Kawanaka
  • Patent number: 8735769
    Abstract: A laser processing head in accordance with the present invention comprises: a laser emitting unit for irradiating a workpiece with a laser light; and a powder feeder disposed around a periphery of the laser emitting unit for discharging filler material powder to the workpiece, in which the powder feeder includes: a position adjustment mechanism for adjusting a position where the powder concentrates; and a powder concentration diameter adjustment mechanism for adjusting a diameter of the filler material powder. The laser processing head further comprises a controller for controlling the position adjustment mechanism and the powder concentration diameter adjustment mechanism.
    Type: Grant
    Filed: October 19, 2010
    Date of Patent: May 27, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Masanori Miyagi, Takeshi Tsukamoto, Hirotsugu Kawanaka
  • Patent number: 8512488
    Abstract: An Ni—Fe based superalloy forging material including 30 to 40 wt % of Fe, 14 to 16 wt % of Cr, 1.2 to 1.7 wt % of Ti, 1.1 to 1.5 wt % of Al, 1.9 to 2.2 wt % of Nb, 0.05 wt % or less of C and the remainder of Ni and inevitable impurities is solution-treated and aged, and thereby ?? phase (Ni3Al) having an initial mean particle size of about 50 to about 100 nm is precipitated. This superalloy is excellent in high-temperature strength and high-temperature ductility and can produce a large forged product of 10 ton or more. Therefore, this material is suitable for use as the material of a steam turbine rotor having a main steam temperature of 650° C. or more.
    Type: Grant
    Filed: August 10, 2007
    Date of Patent: August 20, 2013
    Assignees: Hitachi, Ltd., The Japan Steel Works, Ltd.
    Inventors: Shinya Imano, Hirotsugu Kawanaka, Hiroyuki Doi, Tatsuya Takahashi, Tsukasa Azuma, Koji Kajikawa
  • Patent number: 8481885
    Abstract: A welding apparatus and a welding method are employed for laser narrow groove welding which performs welding scanning a laser beam in the welding direction while feeding a solid filler metal into a narrow groove. The welding apparatus includes a laser beam irradiation head having a mechanism periodically oscillating an irradiation point of the laser beam with a predetermined amplitude in the bottom of the groove, and a filler metal control device having a solid filler metal feeder feeding the solid filler metal to the molten pool formed in the bottom of the groove by the laser beam and adjusting the feeding position independent of a motion of the laser beam irradiation head so that the tip position of the solid filler metal detected is constantly positioned in the center of the groove.
    Type: Grant
    Filed: June 29, 2010
    Date of Patent: July 9, 2013
    Assignee: Hitachi Plant Technologies, Ltd.
    Inventors: Takeshi Tsukamoto, Hirotsugu Kawanaka, Yoshihisa Maeda, Shinji Imaoka, Tetsuya Kuwano, Taiji Hashimoto
  • Publication number: 20120145683
    Abstract: A laser processing system includes a laser processing head, a powder supply device, and a controller. The powder supply device supplies powder to the laser processing head. The laser processing head includes: a laser emission unit which irradiates a workpiece with laser light; and a powder supply unit which receives the powder supplied from a powder supply device to the laser processing head, and can supply the powder to a laser spot on the workpiece. The powder supply unit includes: a powder discharge unit which can discharge the powder toward the laser spot on the workpiece; and a powder-supply control mechanism which controls the amount of the powder to be supplied to the powder discharge unit, by distributing to the powder discharge unit at least a part of a flow of the powder supplied from the powder supply device. The controller controls the distributing by the powder-supply control mechanism.
    Type: Application
    Filed: December 12, 2011
    Publication date: June 14, 2012
    Inventors: Masanori MIYAGI, Takeshi Tsukamoto, Hirotsugu Kawanaka
  • Publication number: 20110248001
    Abstract: In a deposition method of forming a buildup on a single crystal or directionally solidified crystal parent material, metal deposition is performed from an extension in a preferential growth orientation of parent material crystals while forcedly cooling a portion of the parent material somewhat below a processed surface and beforehand giving a temperature gradient to the parent material so that a maximum temperature gradient is oriented along the preferential growth orientation of parent material crystals.
    Type: Application
    Filed: March 28, 2011
    Publication date: October 13, 2011
    Inventors: Hirotsugu KAWANAKA, Takeshi Tsukamoto, Masanori Miyagi
  • Patent number: 8025746
    Abstract: A casing is formed from an alloy which contains, by mass, 0.08-0.20% C, 0.05-0.45% Si, 0.10-0.30% Mn, 0.80-1.40% Ni, 1.00-1.40% Cr, 1.20-1.60% Mo, 0.10-0.30% V, 0.06-0.10% Ti, 0.0005-0.0010% B, not more than 0.01% P, not more than 0.01% S, and not more than 0.005% Al, the balance being Fe and unavoidable impurity elements. The casing has excellent high-temperature strength, high toughness and excellent weldability, and is applicable to casings used in high-temperature high-pressure steam environments.
    Type: Grant
    Filed: March 22, 2007
    Date of Patent: September 27, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Hirotsugu Kawanaka, Masahiko Arai, Tateki Nakamura
  • Publication number: 20110126540
    Abstract: A high-strength heat resisting cast steel which has high creep rupture strength at temperatures of 620° C. or above, high toughness, and good weldability. A method of producing the steel, a steam turbine casing, a main steam valve casing, and a steam control valve casing, each casing being made of that steel, as well as a steam turbine power plant using those components are also provided. The high-strength heat resisting cast steel contains 0.06-0.16% by mass of C, 0.1-1% of Si, 0.1-1% of Mn, 8-12% of Cr, 0.1-1.0% of Ni, 0.7% or less of Mo, 1.9-3.0% of W, 0.05-0.3% of V, 0.01-0.15% of one or more of Nb, Ta and Zr in total, 0.1-2% of Co, 0.01-0.08% of N, and 0.0005-0.01% of B, the balance being Fe and unavoidable impurities.
    Type: Application
    Filed: February 7, 2011
    Publication date: June 2, 2011
    Applicant: HITACHI, LTD.
    Inventors: Masahiko ARAI, Hirotsugu KAWANAKA, Hideo YODA
  • Publication number: 20110089151
    Abstract: A laser processing head in accordance with the present invention comprises: a laser emitting unit for irradiating a workpiece with a laser light; and a powder feeder disposed around a periphery of the laser emitting unit for discharging filler material powder to the workpiece, in which the powder feeder includes: a position adjustment mechanism for adjusting a position where the powder concentrates; and a powder concentration diameter adjustment mechanism for adjusting a diameter of the filler material powder. The laser processing head further comprises a controller for controlling the position adjustment mechanism and the powder concentration diameter adjustment mechanism.
    Type: Application
    Filed: October 19, 2010
    Publication date: April 21, 2011
    Inventors: Masanori MIYAGI, Takeshi Tsukamoto, Hirotsugu Kawanaka
  • Publication number: 20100326969
    Abstract: A welding apparatus and a welding method are employed for laser narrow groove welding which performs welding scanning a laser beam in the welding direction while feeding a solid filler metal into a narrow groove. The welding apparatus includes a laser beam irradiation head having a mechanism periodically oscillating an irradiation point of the laser beam with a predetermined amplitude in the bottom of the groove, and a filler metal control device having a solid filler metal feeder feeding the solid filler metal to the molten pool formed in the bottom of the groove by the laser beam and adjusting the feeding position independent of a motion of the laser beam irradiation head so that the tip position of the solid filler metal detected is constantly positioned in the center of the groove.
    Type: Application
    Filed: June 29, 2010
    Publication date: December 30, 2010
    Inventors: Takeshi TSUKAMOTO, Hirotsugu Kawanaka, Yoshihisa Maeda, Shinji Imaoka, Tetsuya Kuwano, Taiji Hashimoto
  • Publication number: 20100122754
    Abstract: A high-strength martensite heat resisting steel which has long-time creep rupture strength required for steam temperature condition of 600-630° C. and toughness at room temperature, and which is suitable for use as a material of a steam turbine rotor shaft and as large-sized forged steel with an improvement of hot forgeability. A method of producing the steel and applications of the steel are also provided. The high-strength martensite heat resisting steel contains 0.05-0.20% by mass of C, 0.1% or less of Si, 0.05-0.6% of Mn, 0.1-0.6% of Ni, 9.0-12.0% of Cr, 0.20-0.65% of Mo, 2.0-3.0% of W, 0.1-0.3% of V, 2.0% or less of Co, 0.02-0.20% of Nb, 0.015% or less of B, 0.01-0.10% of N, and 0.015% or less of Al, (W/Mo) being 4.0-10.0.
    Type: Application
    Filed: September 28, 2006
    Publication date: May 20, 2010
    Inventors: Hirotsugu Kawanaka, Masahiko Arai, Hideo Yoda
  • Patent number: 7632066
    Abstract: A pipe for a steam turbine is formed of a centrifugal casting material to achieve resistance against higher temperatures and improve reliability of the pipe by employing, as a pipe material, a centrifugal casting material normalized to contain uniform and finer crystal grains. The centrifugal casting material is made of steel having a columnar structure in the radial direction with the crystal grain size number of 5 or more in a plane perpendicular to the radial direction. The steel includes 0.05-0.5% by mass C, not more than 1.0% Si, 0.05-1.5% Mn, 0.01-2.5% Ni, 8.0-13.0% Cr, 0.05-2.5% Mo, not more than 3.0% W, 0.05-0.35% V, 0.01-0.5% Nb, not more than 5% Co, 0.01-0.1% N, not more than 0.03% B, and not more than 0.05% Al.
    Type: Grant
    Filed: July 6, 2006
    Date of Patent: December 15, 2009
    Assignee: Hitachi, Ltd.
    Inventors: Masahiko Arai, Hirotsugu Kawanaka, Hiroyuki Doi, Kenichi Murata, Hajime Toriya
  • Patent number: 7540711
    Abstract: The invention provides a heat resisting steel having superior high-temperature strength and notch rupture strength, a rotor shaft using the heat resisting steel, a steam turbine using the rotor shaft, and a power plant using the steam turbine. The heat resisting steel is made of a Cr—Mo—V low-alloy steel containing 0.15-0.40% by weight of C, not more than 0.5% of Si, 0.05-0.50% of Mn, 0.5-1.5% of Ni, 0.8-1.5% of Cr, 0.8-1.8% of Mo and 0.05-0.35% of V, and having a (Ni/Mn) ratio of 3.0-10.0.
    Type: Grant
    Filed: July 5, 2005
    Date of Patent: June 2, 2009
    Assignee: Hitachi, Ltd.
    Inventors: Masahiko Arai, Hirotsugu Kawanaka, Kennichi Murata, Hideo Yoda
  • Publication number: 20090068052
    Abstract: The invention is of a heat resisting martensitic steel comprising, by weight, 0.05 to 0.30% C, not more than 0.50% Si, not more than 0.60% Mn, 8.0 to 13.0% Cr, 0.5 to 3.0% Ni, 1.0 to 3.0% Mo, 0.1 to 1.5% W, 0.5 to 4% Co, 0.05 to 0.35% V, 0.02 to 0.30% in total of one or two elements selected from the group consisting of Nb and Ta, and 0.02 to 0.10% N, wherein a value of the square of a difference between the Ni amount and the Co amount, and the Ni amount are not more than values determined by a straight line drawn on a point A (1.0, 2.7%) and a point B (2.5, 1.0%) in the orthogonal coordinates shown in the attached drawing of FIG. 2 which represents a relationship between the above square value and the Ni amount, and an amount ratio of Mo/(Mo+0.5W) is not less than 0.5. The heat resisting steel is suitably used in various components of a gas turbine.
    Type: Application
    Filed: May 21, 2008
    Publication date: March 12, 2009
    Applicant: HITACHI, LTD.
    Inventors: Masahiko Arai, Hirotsugu Kawanaka, Hiroyuki Doi, Isao Takehara, Hidetoshi Kuroki
  • Patent number: 7459035
    Abstract: To provide a rotor material preferable for a steam turbine of which main steam temperature is 675° C. or more, particularly exceeding 700° C., and a steam turbine plant having a rotor formed by the material, the invention provides a steam turbine plant including a very-high-pressure turbine of which steam inlet temperature is 675 to 725° C. and steam outlet temperature is 650° C. or less, a high-pressure turbine, and a medium-low-pressure turbine, wherein a rotor of the very-high-pressure turbine is formed from a forged material of NiFe-base alloy containing: 14 to 18 weight % Cr, 15 to 45 weight % Fe, 1.0 to 2.0 weight % Al, 1.0 to 1.8 weight % Ti, C and N of which the sum is 0.05 or less weight %, and Nb in the range specified by the formula: 3.5?(Fe weight %)/20<(Nb weight %)<4.5?(Fe weight %)/20.
    Type: Grant
    Filed: June 10, 2004
    Date of Patent: December 2, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Shinya Imano, Hiroyuki Doi, Hirotsugu Kawanaka, Eiji Saitou
  • Publication number: 20080213099
    Abstract: An Ni—Fe based superalloy forging material including 30 to 40 wt % of Fe, 14 to 16 wt % of Cr, 1.2 to 1.7 wt % of Ti, 1.1 to 1.5 wt % of Al, 1.9 to 2.7 wt % of Nb, 0.05 wt % or less of C and the remainder of Ni and inevitable impurities is solution-treated and aged, and thereby ?? phase (Ni3Al) having an initial mean particle size of about 50 to about 100 nm is precipitated. This superalloy is excellent in high-temperature strength and high-temperature ductility and can produce a large forged product of 10 ton or more. Therefore, this material is suitable for use as the material of a steam turbine rotor having a main steam temperature of 650° C. or more.
    Type: Application
    Filed: August 10, 2007
    Publication date: September 4, 2008
    Inventors: Shinya IMANO, Hirotsugu KAWANAKA, Hiroyuki DOI, Tatsuya TAKAHASHI, Tsukasa AZUMA, Koji KAJIKAWA
  • Publication number: 20070224041
    Abstract: A casing is formed from an alloy which contains, by mass, 0.08-0.20% C, 0.05-0.45% Si, 0.10-0.30% Mn, 0.80-1.40% Ni, 1.00-1.40% Cr, 1.20-1.60% Mo, 0.10-0.30% V, 0.06-0.10% Ti, 0.0005-0.0010% B, not more than 0.01% P, not more than 0.01% S, and not more than 0.005% Al, the balance being Fe and unavoidable impurity elements. The casing has excellent high-temperature strength, high toughness and excellent weldability, and is applicable to casings used in high-temperature high-pressure steam environments.
    Type: Application
    Filed: March 22, 2007
    Publication date: September 27, 2007
    Inventors: Hirotsugu Kawanaka, Masahiko Arai, Tateki Nakamura
  • Publication number: 20070071599
    Abstract: A high-strength heat resisting cast steel which has high creep rupture strength at temperatures of 620° C. or above, high toughness, and good weldability. A method of producing the steel, a steam turbine casing, a main steam valve casing, and a steam control valve casing, each casing being made of that steel, as well as a steam turbine power plant using those components are also provided. The high-strength heat resisting cast steel contains 0.06-0.16% by mass of C, 0.1-1% of Si, 0.1-1% of Mn, 8-12% of Cr, 0.1-1.0% of Ni, 0.7% or less of Mo, 1.9-3.0% of W, 0.05-0.3% of V, 0.01-0.15% of one or more of Nb, Ta and Zr in total, 0.1-2% of Co, 0.01-0.08% of N, and 0.0005-0.01% of B, the balance being Fe and unavoidable impurities.
    Type: Application
    Filed: September 28, 2006
    Publication date: March 29, 2007
    Inventors: Masahiko Arai, Hirotsugu Kawanaka, Hideo Yoda
  • Publication number: 20070014671
    Abstract: A pipe for a steam turbine is formed of a centrifugal casting material to achieve resistance against higher temperatures and improve reliability of the pipe by employing, as a pipe material, a centrifugal casting material normalized to contain uniform and finer crystal grains. The centrifugal casting material is made of steel having a columnar structure in the radial direction with the crystal grain size number of 5 or more in a plane perpendicular to the radial direction. The steel includes 0.05-0.5% by mass C, not more than 1.0% Si, 0.05-1.5% Mn, 0.01-2.5% Ni, 8.0-13.0% Cr, 0.05-2.5% Mo, not more than 3.0% W, 0.05-0.35% V, 0.01-0.5% Nb, not more than 5% Co, 0.01-0.1% N, not more than 0.03% B, and not more than 0.05% Al.
    Type: Application
    Filed: July 6, 2006
    Publication date: January 18, 2007
    Inventors: Masahiko Arai, Hirotsugu Kawanaka, Hiroyuki Doi, Kenichi Murata, Hajime Toriya
  • Publication number: 20060216145
    Abstract: The invention provides a heat resisting steel having superior high-temperature strength and notch rupture strength, a rotor shaft using the heat resisting steel, a steam turbine using the rotor shaft, and a power plant using the steam turbine. The heat resisting steel is made of a Cr—Mo—V low-alloy steel containing 0.15-0.40% by weight of C, not more than 0.5% of Si, 0.05-0.50% of Mn, 0.5-1.5% of Ni, 0.8-1.5% of Cr, 0.8-1.8% of Mo and 0.05-0.35% of V, and having a (Ni/Mn) ratio of 3.0-10.0.
    Type: Application
    Filed: July 5, 2005
    Publication date: September 28, 2006
    Inventors: Masahiko Arai, Hirotsugu Kawanaka, Kennichi Murata, Hideo Yoda