Patents Assigned to Sanyo Special Steel Co., Ltd.
  • Patent number: 6053991
    Abstract: Disclosed are a cold working tool steel suitable for plastic cold working tools used under severe service conditions, such as forming dies, forming rolls, and form rolling dies, and a process for producing the same. The cold working tool steel has wear resistance and tensile compression fatigue strength and at the same time can provide improved die life. The cold working tool steel is characterized by comprising by weight 0.65 to 1.3% of carbon, not more than 2.0% of silicon, 0.1 to 2.0% of manganese, 5.0 to 11.0% of chromium, 0.7 to 5.0%, in terms of molybdenum equivalent (molybdenum+tungsten/2), of at least one member selected from molybdenum and tungsten, 0.1 to 2.5%, in terms of vanadium equivalent (vanadium+niobium/2), of at least one member selected from vanadium and niobium, and optionally 0.010 to 0.10% of sulfur with the balance consisting of iron and unavoidable impurities, an M.sub.7 C.sub.3 carbide having a grain diameter of 5 to 15 .mu.m being present in a percentage area of 1 to 9%.
    Type: Grant
    Filed: May 29, 1998
    Date of Patent: April 25, 2000
    Assignee: Sanyo Special Steel Co., Ltd.
    Inventors: Daien Yokoi, Nobuhiro Tsujii
  • Patent number: 6019517
    Abstract: A bearing outer-race performed piece has a turning stock on an outer periphery thereof and has a circular bearing groove on an inner surface thereof. The bearing groove has a cross-section which includes circular portions defined by a circle of a greater diameter than that of a bearing groove of a bearing outer-race product, and a flat portion being arranged between the circular portions at a location shifted toward the center of the circle of the circular portions from a bottom locus of the circular portions.
    Type: Grant
    Filed: October 23, 1998
    Date of Patent: February 1, 2000
    Assignee: Sanyo Special Steel Co., Ltd.
    Inventors: Manabu Katsuki, Yoshio Kasahara
  • Patent number: 6008891
    Abstract: An automatic flaw removing method for long materials, comprises the steps of: inspecting long materials, such as round-bar steels and steel pipes, for surface flaws by a flaw inspecting apparatus of all section to divide the long materials into rejected materials having a flaw(s) and accepted materials having no flaw; storing information on the longitudinal position and length of each of the flaws of the rejected materials in a storage unit; sequentially carrying out the tracking of each of the rejected materials; moving a circumferential flaw probe directly connected to a grinder, to a longitudinal coordinate position of each of the flaws of the rejected materials, on the basis of the information on the longitudinal position of each of the flaws stored in the storage unit, when each of the rejected materials arrives at a flaw grinding position; rotating each of the rejected materials; identifying a circumferential position of each of the flaws by picking up a flaw indicative signal by the circumferential fla
    Type: Grant
    Filed: November 13, 1997
    Date of Patent: December 28, 1999
    Assignee: Sanyo Special Steel Co., Ltd.
    Inventors: Hiroto Kobayashi, Yoshitomo Tamura, Koji Kawamura, Minoru Nakakusu
  • Patent number: 5989491
    Abstract: A process for producing an oxide dispersion strengthened heat resisting powder metallurgy alloy, characterized in that (1) zirconium and/or a rare earth element, such as yttrium, cerium, or lanthanum, are previously added as an oxide former element to a molten mother alloy, (2) an atomizing gas composed of an argon or nitrogen gas containing not more than 5.0% by volume of oxygen is used in the step of gas-atomizing the molten mother alloy, and (3) in the step of consolidating and molding the gas-atomized alloy powder by rolling, forging, HIP, or hot extrusion, the alloy powder is sieved to a particle diameter of not more than 110 .mu.m before this step. The oxide dispersion strengthened heat resisting powder metallurgy alloy is characterized in that (1) zirconium and/or a rare earth element, such as yttrium, cerium, or lanthanum, are contained in an amount of 0.05 to 3.0% by weight and (2) the powder metallurgy consolidated, molded product prepared by consolidation of the powdery metallurgy alloy contains 0.
    Type: Grant
    Filed: April 4, 1997
    Date of Patent: November 23, 1999
    Assignee: Sanyo Special Steel Co., Ltd.
    Inventors: Tatsuro Isomoto, Tadanori Kida
  • Patent number: 5894752
    Abstract: An axially symmetric ring work piece is formed by a warm or hot, forward and backward extruding, die forging system. In this system, a die having a rearwardly projecting portion, which projects in the opposite direction to a pressing direction, a heated work piece, and a punch having a forwardly projecting portion, are arranged, in that order, in a container. A withdrawal die is arranged between the container, and the heated work piece, the die and the punch. The die is fixed so that a die velocity V.sub.D is 0, and the punch is moved toward the die while a punch velocity V.sub.P is set to be twice as large as a withdrawal die velocity V.sub.WD and the strokes of slide of the withdrawal die are not less than one-half of a forward-extruded foot length of a product. Thus, the forward and backward simultaneous extrusion can be substantially performed in a single-action type, short-stroke, die forging system.
    Type: Grant
    Filed: September 16, 1997
    Date of Patent: April 20, 1999
    Assignee: Sanyo Special Steel Co., Ltd.
    Inventors: Masakazu Yano, Katsuhiko Osaki, Tadatsugu Yoshida, Yoshio Kasahara
  • Patent number: 5788923
    Abstract: A bearing steel is provided which can satisfy bearing property requirements and, at the same time, is improved in mechanical properties, such as impact, crushing, and transverse properties, while reducing the cost of materials and the cost of heat treatment for the production of a bearing. The bearing steel comprises by weight C: 0.70 to 0.93%, Si: 0.15 to 0.50%, Mn: 0.50 to 1.10%, Cr: 0.30 to 0.65%, and N: 0.005 to 0.02% with the balance consisting of Fe and unavoidable impurities and 0.4.ltoreq.Cr/C.ltoreq.0.7, the steel further comprising at least one of (1) Al: 0.01 to 0.1% with Al.times.N.gtoreq.0.00015 and (2) Nb: 0.02 to 0.1%. A rolling bearing produced from the bearing steel is also provided.
    Type: Grant
    Filed: November 1, 1996
    Date of Patent: August 4, 1998
    Assignees: Sanyo Special Steel Co., Ltd., NSK Ltd.
    Inventors: Ryoji Hayashi, Kaneaki Hamada, Yasuo Murakami
  • Patent number: 5542991
    Abstract: A rail for a linear motion guide bearing is fabricated by using a steel which contains C in a range of from 0.56 to 1.0% by weight, Si in a range of up to 0.15% by weight, Mn in a range from 0.20 to 0.40% by weight, Cr in a range of from 0.30 to 0.70% by weight, and B in a range of from 0.0005 to 0.0035% by weight, whereby the hardness of the track surface of the resultant rail is higher than a Vickers hardness of 700, and the die is not decreased in service 1 life by the cold-drawing of the steel.
    Type: Grant
    Filed: May 31, 1994
    Date of Patent: August 6, 1996
    Assignees: NSK Ltd., Sanyo Special Steel Co., Ltd.
    Inventors: Tomoki Muraoka, Tsutomu Abe, Kazuhiro Kobayashi, Kenichi Hosoda
  • Patent number: 5013525
    Abstract: The present invention provides a steel for a corrosion-resistant rolling part having excellent corrosion resistance, high quenching and tempering hardness, and excellent workability for use in linear bearings, ball screws and rolling bearings of industrial machinery which must be strictly prevented from undergoing environmental contamination due to oil and grease. The steel comprises 0.5% or more and 0.7% or less by weight of carbon, 0.1% or more and 1.5% or less by weight of silicon, 0.1% or more and 2.0% or less by weight of manganese, 3.0% or more and less than 6.0%, preferably 4.0% or more and 5.5% or less, by weight of chromium, 0.05% or less by weight of phosphorus, 0.03% or less, preferably 0.01% or less, by weight of sulfur and 0.0015% or less by weight of oxygen, and may further comprise at least one of 0.05% or more and 2.0% or less, preferably 0.05% or more and 1.0% or less, by weight of molybdenum and 0.1% or more and 0.8% or less, preferably 0.2% or more and 0.
    Type: Grant
    Filed: November 28, 1989
    Date of Patent: May 7, 1991
    Assignees: Sanyo Special Steel Co., Ltd., Nippon Seiko Kabushiki Kaisha
    Inventors: Kaneaki Hamada, Kazuichi Tsubota, Tomoki Muraoka
  • Patent number: 4917961
    Abstract: This invention relates to a method of producing a corrosion-, heat- and wear-resistant member which comprises packing an atomized powder of a high-carbon high-chromium steel into a capsule, heating the capsule packed with the powder, then extruding the capsule packed with the powder to obtain a stock not containing carbide grains greater than 3 .mu.m, working the stock, polishing a surface of the stock, and evaporating a film of TiC and/or TiN onto the polished surface, and further a corrosion-, heat- and wear-resistant member produced by the method. The corrosion-, heat- and wear-resistant member according to this invention is suitable for being members for tools used under extremely severe conditions, such as various tools for can manufacturing, molding tools for reinforced plastics, etc.
    Type: Grant
    Filed: August 14, 1989
    Date of Patent: April 17, 1990
    Assignees: Sanyo Special Steel Co., Ltd., Fuji Die Co., Ltd.
    Inventors: Nobuhiro Tsujii, Genryu Abe, Akira Yamaguchi, Minoru Mishuku, Nobujiro Tsuchiya
  • Patent number: 4221922
    Abstract: A water cooled panel particularly useful in an electric furnace for UHP operation, a base plate, and multiple fins, multiple steel channels, each having a specific dimensional relationship to the others.
    Type: Grant
    Filed: November 7, 1978
    Date of Patent: September 9, 1980
    Assignee: Sanyo Special Steel Co., Ltd.
    Inventor: Katutosi Okimune