Patents by Inventor Yoshikuni Ohshima

Yoshikuni Ohshima 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: 4637350
    Abstract: A system for recovering drain which recovers two or more flows or drain of different temperatures, which is applied to a generating plant provided with feed-water heaters in which drain is recovered into a condensation system downstream from a condenser through a drain tank by a drain pump and which comprises a high temperature recovered drain inlet, which is at high temperature and contains much flush steam, and a low temperature drain inlet. The high temperature recovered drain inlet is positioned at a lower part and the low temperature side drain inlet is positioned above the former. This system effects efficient degassing of drain which has high content of dissolved oxygen and efficient control of dissolved oxygen.
    Type: Grant
    Filed: September 30, 1985
    Date of Patent: January 20, 1987
    Assignee: Hitachi, Ltd.
    Inventors: Youshun Horibe, Yoshikuni Ohshima, Toyohiko Masuda
  • Patent number: 4631925
    Abstract: An apparatus for deaerating condensate in a condenser employed in a steam turbine plant, an open conduit to permit the condensate to flow to a covered conduit covered so that the condensate cannot flow therein without passing the open conduit. The condensate is heated in the open conduit, resulting in more effective and quicker deaeration of the condensate and as well as a shortened start up of the plant.
    Type: Grant
    Filed: February 13, 1985
    Date of Patent: December 30, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Katsumoto Ohtake, Yoshikuni Ohshima, Yasuteru Mukai, Isao Okouchi
  • Patent number: 4592419
    Abstract: A condenser for a steam turbine expels the oxygen-containing gas residing in the condensate passage in the hot well thereof by a scavenging steam. The oxygen-containing gas is expelled by the scavenging gas, which is introduced into the atmosphere in the condensate passage and arranged to flow counter to the condensate flow. The scavenging means includes a steam pipe attached in a vicinity of an outlet of the condensate passage in the hot well, and a valve device provided in the intermediate portion of the steam pipe.
    Type: Grant
    Filed: February 6, 1984
    Date of Patent: June 3, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Keizo Ishida, Yoshikuni Ohshima, Toyoyuki Mukaidani, Isao Okouchi, Kenkichi Izumi
  • Patent number: 4529454
    Abstract: A novel low C-Cr-Mo steel having an excellent weldability and a high erosion-corrosion resistance under wet steam, which consists of, in % by weight, 0.02-0.14% of C, not more than 0.90% of Si, 0.30-0.80% of Mn, 0.70-1.60% of Cr, 0.40-0.70% of Mo and the remainder being substantially Fe. This novel steel is a very excellent material for fabricating the portions in the feed-water heater, for example, for a nuclear power generation plant, the portions being used under wet steam condition. The above described weldability and erosion-corrosion resistance can be improved by additionally adding the second components of Cu, N, or B, the third components of Nb or V or the fourth components of Al, Ti or Zr in the respectively defined amounts.
    Type: Grant
    Filed: February 24, 1982
    Date of Patent: July 16, 1985
    Inventors: Fumio Hataya, Masakiyo Izumiya, Yoshikuni Ohshima, Koichi Akutsu, Syuzo Ueda, Masaaki Ishikawa, Yui Kusuhara, Iwao Shiraishi
  • Patent number: 4219077
    Abstract: A multitubular heat exchanger used in a power plant is provided with a bundle of U-shaped heat transfer tubes and a vent tube. The vent tube is located between an upper portion and a lower portion of the bundle of U-shaped heat transfer tubes. A steam flow guide plate is located above a hole of the vent tube and below the upper portion of the bundle of U-shaped heat transfer tubes. The steam flow guide plate obstruct a downward steam flow from the upper portion of the bundle toward the vent tube.
    Type: Grant
    Filed: May 24, 1978
    Date of Patent: August 26, 1980
    Assignee: Hitachi, Ltd.
    Inventors: Masahiro Furukawa, Yoshikuni Ohshima
  • Patent number: RE33006
    Abstract: A novel low C-Cr-Mo steel having an excellent weldability and a high erosion-corrosion resistance under wet steam, which consists of, in % by weight, 0.02-0.14% of C, not more than 0.90% of Si, 0.30-0.80% of Mn, 0.70-1.60% of Cr, 0.40-0.70% of Mo and the remainder being susbtantially Fe. This novel steel is a very excellent material for fabricating the portions in the feed-water heater, for example, for a nuclear power generation plant, the portions being used under wet steam condition. The above described weldability and erosion-corrosion resistance can be improved, by additionally adding the second components of Cu, N, or B, the third components of Nb or V or the fourth components of Al, Ti or Zr in the respectively defined amounts.
    Type: Grant
    Filed: July 8, 1987
    Date of Patent: August 1, 1989
    Assignees: Hitachi, Ltd., Kawasaki Steel Corporation
    Inventors: Fumio Hataya, Masakiyo Izumiya, Yoshikuni Ohshima, Koichi Akutsu, Syuzo Ueda, Masaaki Ishikawa, Yuji Kusuhara, Iwao Shiraishi