Patents by Inventor Nagayasu Bessho

Nagayasu Bessho 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: 7628196
    Abstract: During continuous casting of metals, a non-moving, vibrating magnetic field is applied to a molten metal in a casting mold to impose only vibration on the molten metal. This continuous casting method can produce a cast slab much less susceptible to flux entrainment, capture of bubbles and non-metal inclusions near the surface of the molten metal, and surface segregation. The magnetic field is preferably produced by arranging electromagnets in an opposing relation on both sides of the mold to lie side by side in the direction of longitudinal width of the mold, and supplying a single-phase AC current to each coil. The single-phase AC current preferably has frequency of 0.10 to 60 Hz. A static magnetic field can be applied intermittently in the direction of thickness of a cast slab. This technique can produce a cast slab substantially free from the flux entrainment and the surface segregation. Preferably, the static magnetic field is intermittently applied under setting of an on-time t1=0.
    Type: Grant
    Filed: January 30, 2004
    Date of Patent: December 8, 2009
    Assignee: JFE Steel Corporation
    Inventors: Hiroshi Yamane, Nagayasu Bessho, Yuji Miki, Shuji Takeuchi, Tadasu Kirihara
  • Publication number: 20040182539
    Abstract: During continuous casting of metals, a non-moving, vibrating magnetic field is applied to a molten metal in a casting mold to impose only vibration on the molten metal. This continuous casting method can produce a cast slab much less susceptible to flux entrainment, capture of bubbles and non-metal inclusions near the surface of the molten metal, and surface segregation. The magnetic field is preferably produced by arranging electromagnets in an opposing relation on both sides of the mold to lie side by side in the direction of longitudinal width of the mold, and supplying a single-phase AC current to each coil. The single-phase AC current preferably has frequency of 0.10 to 60 Hz. A static magnetic field can be applied intermittently in the direction of thickness of a cast slab. This technique can produce a cast slab substantially free from the flux entrainment and the surface segregation. Preferably, the static magnetic field is intermittently applied under setting of an on-time t1 0.
    Type: Application
    Filed: January 30, 2004
    Publication date: September 23, 2004
    Applicant: JFE STEEL CORPORATION
    Inventors: Hiroshi Yamane, Nagayasu Bessho, Yuji Miki, Shuji Takeuchi, Tadasu Kirihara
  • Patent number: 6712124
    Abstract: During continuous casting of metals, a non-moving, vibrating magnetic field is applied to a molten metal in a casting mold to impose only vibration on the molten metal. This continuous casting method can produce a cast slab much less susceptible to flux entrainment, capture of bubbles and non-metal inclusions near the surface of the molten metal, and surface segregation. The magnetic field is preferably produced by arranging electromagnets in an opposing relation on both sides of the mold to lie side by side in the direction of longitudinal width of the mold, and supplying a single-phase AC current to each coil. The single-phase AC current preferably has frequency of 0.10 to 60 Hz. A static magnetic field can be applied intermittently in the direction of thickness of a cast slab. This technique can produce a cast slab substantially free from the flux entrainment and the surface segregation. Preferably, the static magnetic field is intermittently applied under setting of an on-time t1=0.
    Type: Grant
    Filed: November 17, 2000
    Date of Patent: March 30, 2004
    Assignee: JFE Steel Corporation
    Inventors: Hiroshi Yamane, Nagayasu Bessho, Yuji Miki, Shuji Takeuchi, Tadasu Kirihara
  • Patent number: 5882377
    Abstract: In this invention, the smelting reduction operation can be carried out in a high efficiency by charging a carbonaceous material in such an amount that total surface area is not less than 60 m.sup.2 per 1 ton of slag weight. Carbon substance finely particulating through thermal crumbling under a high-temperature atmosphere inside the vessel is used as the carbonaceous material, whereby it is possible to stably conduct the smelting reduction while controlling the scattering of the carbonaceous material, and also the erosion, particularly locally erosion of refractory in the smelting reduction furnace, which was a serious problem in the conventional technique, can considerably be decreased to largely prolong the service life of refractory.
    Type: Grant
    Filed: March 5, 1997
    Date of Patent: March 16, 1999
    Assignee: Kawasaki Steel Corporation
    Inventors: Kimiharu Aida, Shuji Takeuchi, Nagayasu Bessho, Tomomichi Terabatake, Yasuo Kishimoto, Hiroshi Nishikawa, Fumio Sudo
  • Patent number: 5775404
    Abstract: This invention proposes a continuous casting method for austenitic stainless steel capable of simultaneously establishing productivity and an excellent surface quality of steel sheet. For this purpose, the invention lies in a method of continuously casting austenitic stainless steel by pouring melt of austenitic stainless steel from a tundish through an immersion nozzle into a continuously casting mold of a continuous slab caster, solidifying it in the mold and continually drawing the resulting slab of given size out from the mold, characterized in that a high-speed continuous casting is carried out so as to satisfy a relation of casting speed, superheating degree of molten steel in the tundish, sectional area of discharge port in the immersion nozzle and slab width represented by the following equation:0.30.ltoreq.V.sup.0.58 .multidot.W.sup.-0.04 .multidot..DELTA.T.multidot.d.sup.-0.96 .ltoreq.0.85whereinV: casting speed (m/min)W: slab width (mm).DELTA.T: superheating degree of molten steel in tundish (.
    Type: Grant
    Filed: September 16, 1996
    Date of Patent: July 7, 1998
    Assignee: Kawasaki Steel Corporation
    Inventors: Yuji Miki, Seiji Itoyama, Nagayasu Bessho, Sumio Yamada, Hiroshi Nomura
  • Patent number: 5759232
    Abstract: A method of charging an iron scrap melting cupola with iron scrap and coke enables the iron scrap to be melted with high energy efficiency. The charging pipe feed is set at a level "h" which meets the condition of h .ltoreq. (r-r') tan .theta., and iron scrap of a quantity Ws meeting the condition of Ws .ltoreq. 1/3.multidot..pi.r.sup.3 .multidot.tan .theta..multidot..rho..sub.s is charged through the charging pipe, followed by charging of coke, wherein h represents the height of the charging feed above the material in the cupola (meters), r represents the inside radius of the cupola (meters), r' represents the inside radius of the charging pipe (meters), .theta. represents the angle of repose of the iron scrap (degrees), Ws represents the quantity of iron scrap per cycle (kg/ch), and .rho..sub.s represents the bulk specific gravity of the iron scrap (kg/m.sup.3).
    Type: Grant
    Filed: March 10, 1997
    Date of Patent: June 2, 1998
    Assignee: Kawasaki Steel Corporation
    Inventors: Yukio Takahashi, Shuji Takeuchi, Nagayasu Bessho
  • Patent number: 5632324
    Abstract: When molten steel jetted through an immersion nozzle into a mold for continuous casting is controlled by applying static field between opposed side walls of the mold for the continuous casting, this invention provides cast slabs having good surface and internal qualities by feeding molten steel to the mold for the continuous casting at a throughput of not less than 6 t/min and simultaneously applying a static field having a magnetic flux density of at least 0.5 T to a meniscus portion in the mold for the continuous casting and a static field having a magnetic flux density of not less than 0.5 T to a lower portion of molten steel jetted out from a discharge port of the immersion nozzle.
    Type: Grant
    Filed: March 7, 1996
    Date of Patent: May 27, 1997
    Assignee: Kawasaki Steel Corporation
    Inventors: Seiko Nara, Akira Idogawa, Nagayasu Bessho, Tetsuya Fujii
  • Patent number: 5570736
    Abstract: A process for continuously casting steel slabs employing a molten steel containing an oxygen concentration of 30 ppm or less, preferably, 20 ppm or less, using a straight immersion nozzle to which an inert gas is not injected, and disposing a static magnetic field generator on the back surface of the mold for applying the strong static magnetic field to the molten steel within the mold, thereby restricting the flow of the molten steel. With this process, it is possible to prevent the nozzle blocking, and hence to obtain the steel slabs excellent in the internal and surface qualities.
    Type: Grant
    Filed: May 19, 1993
    Date of Patent: November 5, 1996
    Assignee: Kawasaki Steel Corporation
    Inventors: Seikou Nara, Hisao Yamazaki, Nagayasu Bessho, Seiji Taguchi, Tetsuya Fujii
  • Patent number: 5375648
    Abstract: An apparatus and method for continuous casting steel. A vertical continuous-casting mold consists of a pair of long side frames and a pair of short side frames formed of a metal having low electrical conductivity. An immersion nozzle supplies molten steel to the mold. An induction heating coil surrounded by a backup frame surrounds the vertical continuous-casting mold. The induction heating coil induction-heats the surface of the molten steel and neighboring portions thereof. The apparatus meets the following conditions;.xi..sup.2 =.sigma..sub.1 /.sigma..sub.2 .ltoreq.41/10.ltoreq. .eta.=(2.mu. .sub.0 .multidot..sigma..sub.2 .multidot..omega.).sup.0.5 .multidot.d.ltoreq. 10where .xi. designates the ratio of electrical conductivity of the mold and the molten steel.sigma..sub.1 designates the electrical conductivity of the mold.sigma..sub.2 designates the electrical conductivity of the molten steel.mu..sub.0 designates the permeability in a vacuumd designates the thickness of the mold.omega.
    Type: Grant
    Filed: September 2, 1993
    Date of Patent: December 27, 1994
    Assignee: Kawasaki Steel Corporation
    Inventors: Akira Idogawa, Nagayasu Bessho, Kenichi Sorimachi, Tetsuya Fujii, Toshikazu Sakuraya
  • Patent number: 5297614
    Abstract: A process for continuous casting of ultra low carbon aluminum killed steel, characterized in that the steel contains 6-20 ppm of calcium, less than 0.01 wt % of sulfur, and less than 30 ppm of oxygen, the molten steel superheat temperature in the tundish is higher than 16.degree. C., and the average flow rate of molten steel is greater than 1.2 m/sec in the straight part of the nozzle. This process prevents rusting and eliminates the necessity of blowing a gas into the immersion nozzle and hence prevents the swelling of cold rolled sheets.
    Type: Grant
    Filed: July 27, 1992
    Date of Patent: March 29, 1994
    Assignee: Kawasaki Steel Corporation
    Inventors: Nagayasu Bessho, Hisao Yamazaki, Tetusya Fujii
  • Patent number: 5265665
    Abstract: In a continuous casting of steel slab, a molten steel is provided having an oxygen concentration of not more than 35 ppm and is supplied from a tundish into a continuous casting mold through a straight immersion nozzle having an open end at the forward end thereof, the mold consisting of a combination of a pair of narrow face mold walls and a pair of wide face mold walls. A traveling magnetic field generating device is disposed on a central area of the outer surface of the wide face mold walls. While the open forward end of the nozzle is positioned in the magnetic field region of the traveling magnetic field generating device, a traveling magnetic field which is perpendicular to the wide face mold walls and which is traveling upward is applied to a flow of the molten steel discharged from the nozzle, thereby controlling the flow. Preferably, an upper or lower static magnetic field generating device or both of them may be also used.
    Type: Grant
    Filed: June 2, 1992
    Date of Patent: November 30, 1993
    Assignee: Kawasaki Steel Corporation
    Inventors: Tetsuya Fujii, Seiko Nara, Nagayasu Bessho, Hisao Yamasaki
  • Patent number: 5127462
    Abstract: A side wall construction for a continuous belt caster includes a metallic side wall body and a refractory layer attached on the central portion of the side wall body. The metallic side wall body has side edge portion extending substantially in flush with the the surface of the refractory layer. The refractory layer is formed with a center projection of essentially triangular cross-section. The height of the peak of the projection is gradually decreased toward downstream of transfer direction of the liquidus and solidus metal. On the other hand, it may be possible to formulate the refractory layer as double layer construction of a heat insulating refractory layer and a wear-resistantive refractory layer.
    Type: Grant
    Filed: May 21, 1991
    Date of Patent: July 7, 1992
    Assignee: Kawasaki Steel Corporation
    Inventors: Saburo Moriwaki, Hitoshi Osugi, Masayuki Onishi, Takao Koshikawa, Nagayasu Bessho, Keiichiro Isomura, Takeshi Higashihara, Tomoaki Kimura
  • Patent number: 4949777
    Abstract: A continuous casting process introduces the factor of rate temperature change for detecting break out in the cast metal. Introduction of rate of temperature change as a parameter representative of the cast metal condition is successful for avoiding the influence of variation of the casting condition, fluctuation of the powder to be introduced between the casting mold wall and the cast metal, casting speed and so forth. For achieving accurate detection of break out of the cast metal by introducing the temperature change factor, casting mold wall temperatures are measured at various measuring points which are circumferentially aligned. Rates of temperature change at each measuring point and average rate of temperature change of all measuring points are derived and compared for making judgement of possible break out when the difference of the rate of temperature change at each measuring point and the average rate of temperature change becomes greater than a predetermined value.
    Type: Grant
    Filed: September 29, 1988
    Date of Patent: August 21, 1990
    Assignee: Kawasaki Steel Corp.
    Inventors: Seiji Itoyama, Kichio Tada, Tsukasa Telashima, Shuji Tanaka, Hiromitsu Yamanaka, Takao Yunde, Hiroaki Iguchi, Nagayasu Bessho
  • Patent number: 4825935
    Abstract: In order to securely hold a moving belt of a continuous casting device against selective movable side walls, a first group of rotatable control rods which are disposed in a first supply header and an adjacent exhaust header are arranged to produce narrow high pressure zones in the film defined between the cooling pad in which the header are formed and the moving belt. These zones can be selectively moved to juxtapose the side walls when the gap between the walls is adjusted. A second group of rotatable control rods which are disposed in second and third supply headers selectively heat the side edges of the belt which are relatively cool as compared with the center section which is exposed to molten metal. As the side walls are moved apart the width of the edge sections which are exposed to pre-heated coolant can be reduced and the amount of normal temperature coolant applied thereto also increased.
    Type: Grant
    Filed: December 9, 1987
    Date of Patent: May 2, 1989
    Assignee: Kawasaki Steel Corporation
    Inventors: Hirokazu Tozawa, Nagayasu Bessho, Tetsuya Fujii, Saburo Moriwaki, Noboru Yasukawa, Tomoaki Kimura
  • Patent number: 4817702
    Abstract: A method and apparatus for continuous casting of an elongated thin metal strip achieves substantially high yield without allowing break-out or sticking. The method for casting a continuous elongated metal strip includes a step of driving endless belts at a varying speed so as to apply jerks to the slightly and half-solidified metal that release the metal from the surfaces of the stationary side walls. Applying jerks to the casting chamber by varying the driving speed of the endless belt ensures that the solidifying metal will travel smoothly and thus ensures a high manufacturing yield.
    Type: Grant
    Filed: September 29, 1987
    Date of Patent: April 4, 1989
    Assignee: Kawasaki Steel Corporation
    Inventors: Seiji Itoyama, Hakaru Nakato, Tsutomu Nozaki, Yasuhiro Habu, Nagayasu Bessho, Tetsuya Fujii
  • Patent number: 4759400
    Abstract: A belt type cast sheet continuous caster of the type comprises a pair of opposed circulatorily movable belts, a pair of opposed side plates arranged along opposite side edge portions of the movable belts, coolers which each have numerous water feed openings and water discharge openings opened to the movable belt and are arranged behind the respective movable belts, and movable partition plates which are placed in respective cooling headers and each connected to driving means for moving the partition plates in a width direction of a cast sheet. A casting space is defined by the movable belt and the side plates.
    Type: Grant
    Filed: October 1, 1986
    Date of Patent: July 26, 1988
    Assignees: Kawasaki Steel Corporation, Hitachi, Ltd.
    Inventors: Nagayasu Bessho, Hirokazu Tozawa, Tetsuya Fujii, Tsutomu Nozaki, Saburo Moriwaki, Noboru Yasukawa, Masaaki Kuga, Michio Suzuki, Nozomu Tamura, Tomoaki Kimura
  • Patent number: 4735254
    Abstract: A method and apparatus for continuous casting of an elongated thin metal strip achieves substantially high yield without allowing break-out or sticking. The method for casting a continuous elongated metal strip includes a step of driving endless belts at a varying speed so as to apply jerks to the slightly and half-solidified metal that release the metal from the surfaces of the stationary side walls. Applying jerks to the casting chamber by varying the driving speed of the endless belt ensures that the solidifying metal will travel smoothly and thus ensures a high manufacturing yield.
    Type: Grant
    Filed: June 27, 1986
    Date of Patent: April 5, 1988
    Assignee: Kawasaki Steel Corporation
    Inventors: Seiji Itoyama, Hakaru Nakato, Tsutomu Nozaki, Yasuhiro Habu, Nagayasu Bessho, Tetsuya Fujii
  • Patent number: 4635703
    Abstract: A cooling pad for use in a continuous casting apparatus for the production of cast sheets. The pad is provided with plural water supply and discharge holes satisfying the particular relations on the arrangement thereof. By using such a cooling pad, a filmy cooling water flow is uniformly and stably formed in the casting.
    Type: Grant
    Filed: August 6, 1985
    Date of Patent: January 13, 1987
    Assignees: Kawasaki Steel Corporation, Hitachi, Ltd.
    Inventors: Hakaru Nakato, Nagayasu Bessho, Tsutomu Nozaki, Yasuhiro Habu, Tomoaki Kimura
  • Patent number: 4353533
    Abstract: A tuyere for blowing an agitating gas into molten steel is arranged in the bottom of an oxygen top-blown converter in order to improve the refining effect of molten steel and has a ratio of blow sectional area S (cm.sup.2) to inner peripheral length L (cm) of not more than 0.17, preferably not more than 0.125.
    Type: Grant
    Filed: February 17, 1981
    Date of Patent: October 12, 1982
    Assignee: Kawasaki Steel Corporation
    Inventors: Tatsukichi Chino, Takuo Imai, Masaaki Tsukamoto, Ryuichi Asaho, Nagayasu Bessho, Kyoji Nakanishi