Patents by Inventor Takaaki Toyooka
Takaaki Toyooka 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).
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Patent number: 6505491Abstract: This invention provides a rolling mill and a rolling-mill train which are compact. Reducers to be coupled with them can be made compact. The inner surfaces of pipes to be rolled with the rolling mill and the rolling-mill train can be prevented from becoming squarish. The rolling mill comprises a plurality of rolls disposed symmetrically around the pathline of the rolling mill, an annular driving bevel gear of a large diameter for driving and rotating the rolls, an input-shaft mechanism for rotating the driving bevel gear, a plurality of transmission mechanisms disposed at regular intervals along the driving bevel gear, and a housing for holding them. The input-shaft mechanism (i) has an input shaft inserted in the housing from its outside and an input bevel gear of a small diameter mounted on the input shaft and engaging with the driving bevel gear and (ii) is disposed between two adjacent transmission mechanisms.Type: GrantFiled: February 14, 2001Date of Patent: January 14, 2003Assignees: Sumitomo Heavy Industries, Ltd., Kawasaki Steel CorporationInventors: Shigeharu Ochi, Hiroshi Fujiwara, Sho Inui, Takaaki Toyooka, Motoaki Itadani, Akira Yorifuji, Toshio Onishi, Koji Sugano, Yasuo Nishida, Nobuki Tanaka
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Publication number: 20030008171Abstract: A welded steel pipe is formed by heating or soaking an untreated welded steel pipe having a steel composition containing, on the basis of mass percent: about 0.03% to about 0.2% C, about 2.0% or less of Si, not less than about 1.0% to about 1.5% Mn, about 0.1% or less of P, about 0.01% or less of S, about 1.0% or less of Cr, about 0.1% or less of Al, about 0.1% or less of Nb, about 0.1% or less of Ti, about 0.1% or less of V, and about 0.01% or less of N; and by reduction-rolling the treated steel pipe at a cumulative reduction rate of at least about 35% and a final rolling temperature of about 500° C. to about 900° C. The welded steel pipe exhibits excellent hydroformability, i.e., has a tensile strength of at least about 590 MPa and an n×r product of at least about 0.22. The treated steel pipe is preferably reduction-rolled at a cumulative reduction rate of at least about 20% below the Ar3 transformation point.Type: ApplicationFiled: May 31, 2002Publication date: January 9, 2003Applicant: KAWASAKI STELL CORPORATIONInventors: Takaaki Toyooka, Masatoshi Aratani, Yoshikazu Kawabata, Yuji Hashimoto, Akira Yorifuji, Takatoshi Okabe, Takuya Nagahama, Mitsuo Kimura
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Publication number: 20020192495Abstract: A welded steel pipe is formed by heating or soaking an untreated welded steel pipe having a steel composition containing, on the basis of mass percent: about 0.05 % to about 0.2% C; about 0.2% or less of Si; about 1.5% or less of Mn; about 0.1% or less of P; about 0.01% or less of S; about 0.1% or less of Al; and about 0.01 % or less of N; and by reduction-rolling the treated steel pipe at a cumulative reduction rate of at least about 35% and a final rolling temperature of about 500° C. to about 900° C. The welded steel pipe exhibits excellent hydroformability, i.e., has a tensile strength of at least about 400 MPa and an n×r product of at least about 0.22. The treated steel pipe is preferably reduction-rolled at a cumulative reduction rate of at least about 20% below the Ar3 transformation point. The welded steel pipe is suitable for forming structural components.Type: ApplicationFiled: May 31, 2002Publication date: December 19, 2002Applicant: Kawasaki Steel CorporationInventors: Takaaki Toyooka, Masatoshi Aratani, Yoshikazu Kawabata, Yuji Hashimoto, Akira Yorifuji, Takatoshi Okabe, Takuya Nagahama, Mitsuo Kimura
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Publication number: 20020170637Abstract: A high-strength, high-toughness seamless steel pipe used for a line pipe contains 0.03 to 0.06% of C, 0.05 to 0.15% of Si, 1.6 to 2.0% of Mn, 0.010 to 0.10% of Al, 0.3 to 0.7% of Ni, 0.10 to 0.40% of Mo, 0.01 to 0.06% of V, 0.003 to 0.03% of Nb, 0.003 to 0.020% of Ti, and 0.0010 to 0.0100% of N, the relationships Mo+5V≧0.4% and 2Nb−V≦0% being satisfied, and the balance being Fe and incidental impurities. Consequently, it is possible to provide the high-strength, high-toughness seamless steel pipe used for a line pipe in which grade X80 strength and toughness are stably ensured, and the target strength can be easily attained regardless of the size.Type: ApplicationFiled: August 29, 2001Publication date: November 21, 2002Inventors: Yukio Miyata, Mitsuo Kimura, Takaaki Toyooka, Noritsugu Itakura
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Publication number: 20020153070Abstract: The invention provides a high-carbon steel pipe having superior cold workability and induction hardenability, and a method of producing the steel pipe. The method comprises the steps of heating or soaking a base steel pipe having a composition containing C: 0.3 to 0.8%, Si: not more than 2%, and Mn: not more than 3%, and then carrying out reducing rolling on the base steel pipe at least in the temperature range of (Ac1, transformation point −50° C.) to Ac1, transformation point with an accumulated reduction in diameter of not less than 30%. A structure in which the grain size of cementite is not greater than 1.0 &mgr;m is obtained, thus resulting in improved cold workability and induction hardenability.Type: ApplicationFiled: January 29, 2002Publication date: October 24, 2002Inventors: Takaaki Toyooka, Yoshikazu Kawabata, Akira Yorifuji, Masanori Nishimori, Motoaki Itadani, Takatoshi Okabe, Masatoshi Aratani, Yasue Koyama
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Patent number: 6464802Abstract: A high-Cr steel pipe for line pipes having further improved HAZ toughness and hot workability is provided by limiting the composition to: C: 0.02% or less, Si: 0.5% or less, Mn: 0.2 to 3.0%, Cr: 10.0 to 14.0%, Ni: more than 2.0 to 3.0%, N: 0.02% or less, preferably Nb: 0.3% or less, and the balance being Fe and incidental impurities.Type: GrantFiled: October 2, 2000Date of Patent: October 15, 2002Assignee: Kawasaki Steel CorporationInventors: Yukio Miyata, Mitsuo Kimura, Takaaki Toyooka
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Patent number: 6375059Abstract: A method and apparatus for smoothing a thick walled portion of a steel pipe produced by pressure-welding two opposite longitudinal edges of an open pipe with a squeeze roll after being subjected to induction heating. Outer and inner reduction rollers pressure sandwiches the thick walled portion from the outer and inner surfaces of the pipe, a support supports the inner reduction roller to be rotatable and containing a water passage for cooling water, a connecting rod connects the support device to a coupler and contains a further water passage for feeding cooling water to the water passage, and an anchor holds the connecting rod. In the method of producing steel pipes two opposite longitudinal edges of the open pipe are preformed before being subjected to the induction heating and thereafter a thick walled portion is smoothed by the above-described.Type: GrantFiled: January 16, 2001Date of Patent: April 23, 2002Assignee: Kawasaki Steel CorporationInventors: Toshio Ohnishi, Masahiro Kagawa, Yoshnori Sugie, Koji Sugano, Nobuki Tanaka, Kingo Sawada, Masao Shoji, Takaaki Toyooka, Yuji Hashimoto, Motoaki Itadani, Akira Yorifuji, Masanori Nishimori
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Patent number: 6331216Abstract: The steel pipe has a structure composed mainly of ferrite or ferrite plus pearlite or ferrite plus cementite. The steel pipe is characterized by grain size not greater than 3 &mgr;m, preferably not greater than 1 &mgr;m, elongation greater than 20%, tensile strength (TS:MPa) and elongation (E1:%) whose product is greater than 10000, and percent ductile fracture greater than 95%, preferably 100%, measured by Charpy impact test on an actual pipe at −100° C. The structure is characterized by C: 0.005-0.03%, Si: 0.01-3.0%, Mn: 0.01-2.0%, and Al: 0.001-0.10% on a weight basis, and is composed of ferrite or ferrite and a secondary phase, with ferrite grains being not greater than 3 &mgr;m and the secondary phase having an areal ratio not more than 30%. A steel pipe stock having the above-mentioned composition is heated at a temperature of (Ac1+50° C.) to 400° C. and subsequently reduced at a rolling temperature of (Ac1+50° C.) to 400° C.Type: GrantFiled: December 30, 1998Date of Patent: December 18, 2001Assignee: Kawasaki Steel CorporationInventors: Takaaki Toyooka, Akira Yorifuji, Masanori Nishimori, Motoaki Itadani, Yuji Hashimoto, Takatoshi Okabe, Nobuki Tanaka, Taro Kanayama, Osamu Furukimi, Masahiko Morita, Takaaki Hira, Saiji Matsuoka
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Publication number: 20010027831Abstract: A steel pipe containing fine ferrite crystal grains, which has excellent toughness and ductility and good ductility-strength balance as well as superior collision impact resistance, and a method for producing the same are provided. A steel pipe containing super-fine crystal grains can be produced by heating a base steel pipe having ferrite grains with an average crystal diameter of di (&mgr;m), in which C, Si, Mn and Al are limited within proper ranges, and if necessary, Cu, Ni, Cr and Mo, or Nb, Ti, V, B, etc. are further added, at not higher than the Ac3 transformation point, and applying reducing at an average rolling temperature of &thgr;m (° C.) and a total reduction ratio Tred (%) within s temperature range of from 400 to Ac3 transformation point, with di, &thgr;m and Tred being in a relation satisfying a prescribed equation.Type: ApplicationFiled: January 30, 2001Publication date: October 11, 2001Applicant: Kawasaki Steel CorporationInventors: Takaaki Toyooka, Akira Yorifuji, Masanori Nishimori, Motoaki Itadani, Yuji Hashimoto, Takatoshi Okabe, Taro Kanayama, Masahiko Morita, Saiji Matsuoka, Nobuki Tanaka, Osamu Furukimi, Takaaki Hira
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Publication number: 20010027673Abstract: This invention provides a rolling mill and a rolling-mill train which are compact. Reducers to be coupled with them can be made compact. The inner surfaces of pipes to be rolled with the rolling mill and the rolling-mill train can be prevented from becoming squarish. The rolling mill comprises a plurality of rolls disposed symmetrically around the pathline of the rolling mill, an annular driving bevel gear of a large diameter for driving and rotating the rolls, an input-shaft mechanism for rotating the driving bevel gear, a plurality of transmission mechanisms disposed at regular intervals along the driving bevel gear, and a housing for holding them. The input-shaft mechanism (i) has an input shaft inserted in the housing from its outside and an input bevel gear of a small diameter mounted on the input shaft and engaging with the driving bevel gear and (ii) is disposed between two adjacent transmission mechanisms.Type: ApplicationFiled: February 14, 2001Publication date: October 11, 2001Inventors: Shigeharu Ochi, Hiroshi Fujiwara, Sho Inui, Takaaki Toyooka, Motoaki Itadani, Akira Yorifuji, Toshio Onishi, Koji Sugano, Yasuo Nishida, Nobuki Tanaka
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Patent number: 6290789Abstract: A steel pipe containing fine ferrite crystal grains, which has excellent toughness and ductility and good ductility-strength balance as well as superior collision impact resistance, and a method for producing the same are provided. A steel pipe containing super-fine crystal grains can be produced by heating a base steel pipe having ferrite grains with an average crystal diameter of di (&mgr;m), in which C, Si, Mn and Al are limited within proper ranges, and if necessary, Cu, Ni, Cr and Mo, or Nb, Ti, V, B, etc. are further added, at not higher than the Ac3 transformation point, and applying reducing at an average rolling temperature of &thgr;m (°C.) and a total reduction ration Tred (%) within s temperature range of from 400 to Ac3 transformation point, with di, &thgr;m and Tred being in a relation satisfying a prescribed equation.Type: GrantFiled: February 26, 1999Date of Patent: September 18, 2001Assignee: Kawasaki Steel CorporationInventors: Takaaki Toyooka, Akira Yorifuji, Masanori Nishimori, Motoaki Itadani, Yuji Hashimoto, Takatoshi Okabe, Taro Kanayama, Masahiko Morita, Saiji Matsuoka, Nobuki Tanaka, Osamu Furukimi, Takaaki Hira
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Publication number: 20010013533Abstract: A method and apparatus for smoothing a thick walled portion of a steel pipe produced by pressure-welding two opposite longitudinal edges of an open pipe with a squeeze roll after being subjected to induction heating. Outer and inner reduction rollers pressure sandwiches the thick walled portion from the outer and inner surfaces of the pipe, a support supports the inner reduction roller to be rotatable and containing a water passage for cooling water, a connecting rod connects the support device to a coupler and contains a further water passage for feeding cooling water to the water passage, and an anchor holds the connecting rod. In the method of producing steel pipes two opposite longitudinal edges of the open pipe are preformed before being subjected to the induction heating and thereafter a thick walled portion is smoothed by the above-described.Type: ApplicationFiled: January 16, 2001Publication date: August 16, 2001Applicant: Kawasaki Steel CorporationInventors: Toshio Ohnishi, Masahiro Kagawa, Yoshnori Sugie, Koji Sugano, Nobuki Tanaka, Kingo Sawada, Masao Shoji, Takaaki Toyooka, Yuji Hashimoto, Motoaki Itadani, Akira Yorifuji, Masanori Nishimori
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Patent number: 6216520Abstract: A rolling mill comprising a roll unit and a drive unit for driving the roll unit. The drive unit comprises an outer housing, a pair of large-diameter ring-like driving bevel gears disposed concentric with the pass line, an input shaft mechanism for rotating the driving bevel gears, and transmission mechanisms for transmitting the torque of the driving bevel bears to the rolls. Each transmission mechanism comprises a small-diameter transmission bevel gear caught between and engaging with the driving bevel gears and first and second transmission shafts for transmitting the torque of the transmission bevel gear to a roll. The drive and roll units are coupled and uncoupled by couplings. Four positioning parts are formed on the outer periphery of the inner housing of the roll unit. The outer housing of the drive unit is generally in the shape of a ring, and four positioning parts are formed on the inner periphery of the outer housing.Type: GrantFiled: August 18, 1999Date of Patent: April 17, 2001Assignees: Kawasaki Steel Corporation, Sumitomo Heavy Industries, LTDInventors: Shigeharu Ochi, Hiroshi Fujiwara, Sho Inui, Takaaki Toyooka, Motoaki Itadani, Akira Yorifuji, Toshio Onishi, Koji Sugano, Mikio Kodaka, Nobuki Tanaka
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Patent number: 6216940Abstract: A forming stand for continuously forming a skelp material into a pipe, by pressure of spaced-apart forming rolls supported by spaced upper and lower shafts, the forming rolls having two portions, with one portion fixedly fitted on one side of its shaft, a sleeve slidably fitted to the other end of the shaft and fixedly secured to the sleeve and slidable with respect to the shaft; a bearing box for supporting one side of the associated shaft; a bearing box supporting the other side of the associated shaft through the sleeve; upper and lower stand supporting frames for supporting both of the bearing boxes to be movable in an axial direction; and supporting columns for supporting the stand supporting frames; the pipe-forming force is continuously measured and the forming operation is adjusted such that the measured value of pipe-forming force does not exceed a predetermined pipe-forming upper limit.Type: GrantFiled: February 17, 2000Date of Patent: April 17, 2001Assignees: Kawasaki Steel Corporation, Kusakabe Electric & Machinery Co., Ltd., both ofInventors: Koji Sugano, Masahiro Kagawa, Toshio Ohnishi, Kingo Sawada, Yoshinori Sugie, Nobuki Tanaka, Takaaki Toyooka, Motoaki Itadani, Yuji Hashimoto, Ryoji Kusakabe, Kazuo Omura
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Patent number: 6216511Abstract: A method and apparatus for smoothing a thick walled portion of a steel pipe produced by pressure-welding two opposite longitudinal edges of an open pipe with a squeeze roll after being subjected to induction heating. Outer and inner reduction rollers pressure sandwiches the thick walled portion from the outer and inner surfaces of the pipe, a support supports the inner reduction roller to be rotatable and containing a water passage for cooling water, a connecting rod connects the support device to a coupler and contains a further water passage for feeding cooling water to the water passage, and an anchor holds the connecting rod. In the a method of producing steel pipes two opposite longitudinal edges of the open pipe are preformed before being subjected to the induction heating and thereafter a thick walled portion is smoothed by the above-described apparatus.Type: GrantFiled: March 27, 1998Date of Patent: April 17, 2001Assignee: Kawasaki Steel CorporationInventors: Toshio Ohnishi, Masahiro Kagawa, Yoshnori Sugie, Koji Sugano, Nobuki Tanaka, Kingo Sawada, Masao Shoji, Takaaki Toyooka, Yuji Hashimoto, Motoaki Itadani, Akira Yorifuji, Masanori Nishimori
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Plug and mandrel bar for seamless steel pipe rolling operation for manufacturing seamless steel pipe
Patent number: 6202463Abstract: This invention provide a plug and a mandrel bar for use in rolling a seamless steel pipe of which life can be substantially improved more than that of the prior art under a severe condition of use always exposed to a high temperature and high load. The entire plug or the mandrel bar or at least the surface layer of the extremity end and the work section of it is made of ceramics. In addition, this invention provides a method for manufacturing a seamless steel pipe using such a plug or mandrel bar as described above.Type: GrantFiled: January 15, 1999Date of Patent: March 20, 2001Assignee: Kawasaki Steel CorporationInventors: Akira Yorifuji, Takaaki Toyooka, Taro Kanayama -
Patent number: 6136109Abstract: A high-Cr martensite steel pipe having excellent pitting resistance and method for manufacturing the same, which involves forming a pipe of steel including C: about 0.03 wt % or less, Si: about 0.5 wt % or less, Mn: about 0.5-3.0 wt %, Cr: about 10.0-14.0 wt %, Ni: about 0.2-2.0 wt %, Cu: about 0.2-1.0 wt % and N: about 0.03 wt % or less with the balance being Fe and incidental impurities, and having a value X shown as defined in the following formula (1) of about 12.2 or more. The pipe is quenched after austenitizing it at a temperature substantially equal to an A.sub.C3 point or higher, and the pipe is annealed in a temperature range from about 550.degree. C. or higher to a temperature lower than an A.sub.C1 point.Type: GrantFiled: October 28, 1998Date of Patent: October 24, 2000Assignee: Kawasaki Steel CorporationInventors: Yukio Miyata, Mitsuo Kimura, Tomoya Koseki, Takaaki Toyooka, Fumio Murase
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Patent number: 6095957Abstract: High-quality high-speed steel roll which is markedly excellent in abrasion resistance and free of carbide segregation even in the case of production by centrifugal casting of economical benefit; it comprises an outer layer containing, by all weight ratios, C; 2.4-2.9%, Si; not more than 1%, Mn; not more than 1%, Cr; 12-18%, Mo; 3-9%, V; 3-8% and Nb; 0.5-4%, and meeting with the following equations (1) and (2) at one time,0.27.gtoreq.Mo (%)/Cr (%).ltoreq.0.7 (1)C (%)+0.2.multidot.Cr (%).ltoreq.6.2 (2)the outer layer further containing as the balance Fe and unavoidable impurities.Type: GrantFiled: January 29, 1998Date of Patent: August 1, 2000Assignee: Kawasaki Steel CorporationInventors: Kenji Ichino, Tomoya Koseki, Takaaki Toyooka, Kohji Yuda
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Patent number: 6041632Abstract: A forming stand for continuously forming a skelp material into a pipe, by pressure of spaced-apart forming rolls supported by spaced upper and lower shafts, the forming rolls having two portions, with one portion fixedly fitted on one side of its shaft, a sleeve slidably fitted to the other end of the shaft and fixedly secured to the sleeve and slidable with respect to the shaft; a bearing box for supporting one side of the associated shaft; a bearing box supporting the other side of the associated shaft through the sleeve; upper and lower stand supporting frames for supporting both of the bearing boxes to be movable in an axial direction; and supporting columns for supporting the stand supporting frames; the pipe-forming force is continuously measured and the forming operation is adjusted such that the measured value of pipe-forming force does not exceed a predetermined pipe-forming upper limit.Type: GrantFiled: September 8, 1998Date of Patent: March 28, 2000Assignees: Kawasaki Steel Corporation, Kusakabe Electric & Machinery Co., Ltd.Inventors: Koji Sugano, Masahiro Kagawa, Toshio Ohnishi, Kingo Sawada, Yoshinori Sugie, Nobuki Tanaka, Takaaki Toyooka, Motoaki Itadani, Yuji Hashimoto, Ryoji Kusakabe, Kazuo Omura
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Patent number: 6006789Abstract: A steel mother pipe obtained by a solid phase butt-welding pipe-making process or a welding pipe-making process is reduced by heating the pipe prior to the reduction at a temperature exceeding 100.degree. C. and lower than 800.degree. C. wherein the temperature of the steel pipe being reduced is controlled within a defined range. The temperature difference along the circumferential direction of the mother pipe at the inlet side of a reducer is within a defined range, and the temperature of the steel pipe at interstand positions of the reducer is also controlled. By virtue of this control, the reduction becomes possible at low load while suppressing work hardening without degrading surface properties. The resultant product pipe has a dimensional accuracy maintained at a high level.Type: GrantFiled: January 31, 1997Date of Patent: December 28, 1999Assignee: Kawasaki Steel CorporationInventors: Takaaki Toyooka, Akira Yorifuji, Motoaki Itadani, Toshio Ohnishi, Yuji Hashimoto, Nobuki Tanaka, Hiroyuki Matsui