Patents by Inventor Masaharu Ueda

Masaharu Ueda 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: 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: 5762723
    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.degree. to 10.degree. C./sec from an austenite zone temperature to a cooling stop temperature of 700.degree. to 500.degree. 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: July 15, 1996
    Date of Patent: June 9, 1998
    Assignee: Nippon Steel Corporation
    Inventors: Masaharu Ueda, Hideaki Kageyama, Kouichi Uchino, Koji Babazono, Ken Kutaragi
  • 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: 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