Pipe Or Tube Patents (Class 148/590)
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Patent number: 7736447Abstract: Ultra-high-strength linepipes having excellent low-temperature toughness manufactured by welding together the edges of steel plates comprising C of 0.03 to 0.07 mass %, Si of not more than 0.6 mass %, Mn of 1.5 to 2.5 mass %, P of not more than 0.015 mass %, S of not more than 0.003 mass %, Ni of 0.1 to 1.5 mass %, Mo of 0.15 to 0.60 mass %, Nb of 0.01 to 0.10 mass %, Ti of 0.005 to 0.030 mass %, Al of not more than 0.06 mass %, one or more of required amounts of B, N, V, Cu, Cr, Ca, REM (rare-earth metals) and Mg, with the remainder consisting of iron and unavoidable impurities and having a (Hv-ave)/(Hv-M) ratio between 0.8 and 0.9 at 2.5?P?4.0, wherein Hv-ave is the average Vickers hardness in the direction of the thickness of the base metal and Hv-M is the martensite hardness depending on C-content (Hv-M=270+1300C) and a tensile strength TS-C between 900 MPa and 1100 MPa; P=2.7C+0.4Si+Mn+0.8Cr+0.45(Ni+Cu)+(1+?)Mo?1+? (?=1 when B?3 ppm and ?=0 when B<3 ppm).Type: GrantFiled: December 17, 2004Date of Patent: June 15, 2010Assignees: Nippon Steel Corporation, Exxonmobil Upstream Research CompanyInventors: Hitoshi Asahi, Takuya Hara
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Publication number: 20100132854Abstract: Iron-based alloys and articles in strips, sheets, workpieces and the like are converted into high strength steel with a minimum of cost, time and effort, including producing dual phase materials. This is achievable by extremely rapid micro-treating of low, medium, and high carbon iron-based alloys and articles by rapid heating and rapid cooling at least a portion of the alloy/article. This heating step involves nearly immediately heating the iron-based alloy to a selected temperature above its austenite conversion temperature. Then, the alloy is immediately quenched, also at an extremely fast rate, on at least a portion of the iron-based alloy in a quenching unit adjacent the heating unit. This procedure forms high strength alloy in a desired area, depending upon where the treatment was performed.Type: ApplicationFiled: October 3, 2007Publication date: June 3, 2010Inventor: Gary M. Cola, JR.
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Publication number: 20100119860Abstract: The invention provides a steel pipe excellent in deformation characteristics, most notably a steel pipe for expandable-pipe oil well and a low-yield-ratio line pipe, and a method of producing the same without conducting water cooling requiring large-scale heat treatment equipment, namely a method of producing a steel pipe excellent in deformation characteristics whose microstructure is a two-phase structure including a martensite-austenite constituent at an area fraction of 2 to 10% and a soft phase, which method comprises: heating at Ac1+10° C. to Ac1+60° C. and thereafter cooling a precursor steel pipe which contains, in mass %, C: 0.04 to 0.10% and Mn: 1.00 to 2.50%, is limited to Si: 0.80% or less, P: 0.03% or less, S: 0.01% or less, Al: 0.10% or less and N: 0.01% or less, further contains one or more of Ni: 1.00% or less, Mo: 0.60% or less, Cr: 1.00% or less and Cu: 1.00% or less, where content of Mn and content of one or more of Cr, Ni, Mo and Cu satisfy Mn+Cr+Ni+2Mo+Cu?2.Type: ApplicationFiled: July 22, 2008Publication date: May 13, 2010Inventors: Asahi Hitoshi, Tetsuo Ishitsuka, Motofumi Koyuba, Toshiyuki Ogata
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Publication number: 20100065166Abstract: A steel pipe with excellent expandability, comprises, by mass %, C: 0.1 to 0.45%, Si: 0.3 to 3.5%, Mn: 0.5 to 5%, P: less than or equal to 0.03%, S: less than or equal to 0.01%, soluble Al: 0.01 to 0.8% (more than or equal to 0.1% in case Si content is less than 1.5%), N: less than or equal to 0.05%, O: less than or equal to 0.01%, and balance being Fe and impurities, having a mixed microstructure comprising ferrite and one or more selected from fine pearlite, bainite and martensite, and has a tensile strength of more than or equal to 600 MPa and a uniform elongation satisfying the following formula u-el?28?0.0075 TS, wherein u-el is uniform elongation (%) and TS is tensile strength (MPa).Type: ApplicationFiled: October 7, 2009Publication date: March 18, 2010Inventors: Kunio Kondo, Yuji Arai
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Publication number: 20100051143Abstract: A case hardening steel tube which has a hardness of 72-80 HRB and which gives a carburized layer with a high strength and high wear resistance and adequate resistance to impact fracture when it is formed into a final product by working and subsequent carburizing and quenching under relatively mild conditions is manufactured by forming a tube from a steel having a steel composition comprising, in mass percent, C: 0.1-0.25%, Si: 0.2-0.4%, Mn: 0.3-0.9%, P: at most 0.02%, S: 0.001-0.15%, Cr: 0.5-0.9%, Mo: 0.15-1%, Al: 0.01-0.1%, B: 0.0005-0.009%, N: less than 0.006%, and a remainder essentially of Fe, then subjecting the resulting steel tube to normalizing by soaking at a temperature of 880-980° C. followed by cooling at a cooling rate of at most 70° C. per minute, carrying out cold working of the normalized steel tube, and then annealing the cold worked steel tube at a temperature of 700-820° C.Type: ApplicationFiled: September 10, 2009Publication date: March 4, 2010Applicant: SUMITOMO METAL INDUSTRIES, LTD.Inventor: Kenichi Beppu
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Publication number: 20100043926Abstract: A method for preventing carbon steel from intergranular cracking utilizing a reducing gas instead of nitrogen gas for a heat treatment of feeder pipes for a pressurized heavy water reactor (PHWR) nuclear power plant. This heat treatment protects carbon from oxidation to prevent the formation of decarburized layers so that the feeder pipes can be prevented from intergranular cracking. In addition, intergranular segregation of impurities is inhibited and intergranular strength of the carbon steel is enhanced. Therefore, no intergranular cracking occurs despite the concentration of stress.Type: ApplicationFiled: October 28, 2008Publication date: February 25, 2010Inventors: Nam Hoe HEO, Hong Deok Kim, Ki Tae Kim, Jung Kuk Lee, Yong Chan Jung
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Patent number: 7621323Abstract: A very low carbon steel alloy is provided for use in manufacturing tubular members such as oil country tubular goods. The tubular members may be radially expanded from at least twenty percent to forty percent. Sections or joints of casing formed from the steel alloy may be installed within a wellbore and radially expanded during completion of the wellbore.Type: GrantFiled: July 23, 2008Date of Patent: November 24, 2009Assignee: United States Steel CorporationInventors: Gary M. Reavis, Bluford W. Lowery, Ralph R. Myers, Bowman A. Urech
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Publication number: 20090183805Abstract: A method of cooling a steel pipe which can effectively suppress quenching-induced bending which occurs when quenching a thin-walled steel pipe with a wall thickness/outer diameter ratio of at most 0.07 without decreasing the manufacturing efficiency of the steel pipe comprises cooling the inner surface of the steel pipe by spraying cooling water into the interior of a horizontally-disposed steel pipe 2 while rotating the pipe in its circumferential direction, and the outer surface is cooled by producing a downward flow of cooling water streams 5a and 5b in a planar shape from above onto the outer surface along the axial direction of the steel pipe 2. Cooling of the inner surface is started at least 7 seconds before cooling of the outer surface.Type: ApplicationFiled: December 1, 2008Publication date: July 23, 2009Inventors: Hajime Osako, Junji Nakata
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Patent number: 7559251Abstract: Disclosed is an apparatus and method for forming thermal fatigue cracks in a test piece for performance demonstration of nondestructive testing. The apparatus for forming thermal fatigue cracks includes a heating unit, having a conductive member attached around the outer surface of a pipe test piece and an induction heating coil disposed adjacent to the conductive member; a cooling unit, having a cooling water pump for forcibly supplying cooling water to the inner surface of the pipe test piece from a cooling water storage source and a cooling water hose; and a control unit for controlling operation of the heating unit and the cooling unit. Accordingly, thermal fatigue cracks similar to actual thermal fatigue cracks occurring during the operation of nuclear power plants or processing industry equipment are formed in a test piece, thereby assuring effective performance demonstration of nondestructive testing.Type: GrantFiled: January 22, 2007Date of Patent: July 14, 2009Inventors: Bo-Young Lee, Duck Hee Ryu, Jae Seong Kim, Yong Kim, Dae Hwan An
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Patent number: 7540402Abstract: The present invention provides a method for welding and heat-treating seam-welded constructions of hardenable steel and ferrous alloys with reduced weld-zone hardness and improved weld-zone ductility and toughness. This method consists of controlling the cooling rate of the seam weld with a secondary heat source, applied after the weld cools below the materials upper critical temperature (AC3), but prior to the weld cooling to ambient temperature. This invention is particularly suited to the production of high strength hardenable alloy seam-welded pipe and tubing.Type: GrantFiled: January 10, 2008Date of Patent: June 2, 2009Assignee: KVA, Inc.Inventors: Edward J. McCrink, Daniel S. Codd
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Publication number: 20090032150Abstract: An oil country tubular good for expansion according to the invention is expanded in a well. The oil country tubular good for expansion has a composition containing, in percentage by mass, 0.05% to 0.08% C, at most 0.50% Si, 0.80% to 1.30% Mn, at most 0.030% P, at most 0.020% S, 0.08% to 0.50% Cr, at most 0.01% N, 0.005% to 0.06% Al, at most 0.05% Ti, at most 0.50% Cu, and at most 0.50% Ni, and the balance consisting of Fe and impurities, and a structure having a ferrite ratio of at least 80%. The oil country tubular good for expansion has a yield strength in the range from 276 MPa to 379 MPa and a uniform elongation of at least 16%. Therefore, the oil country tubular good according to the invention has a high pipe expansion characteristic.Type: ApplicationFiled: September 29, 2008Publication date: February 5, 2009Inventors: Taro Ohe, Keiichi Nakamura, Hideki Takabe, Toshiharu Abe, Tomoki Mori, Masakatsu Ueda
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Publication number: 20080286504Abstract: The present invention provides steel plate or steel pipe with small occurrence of the Bauschinger effect and methods of production of the same, particularly steel pipe used for steel pipe for oil wells or line pipe with a small drop in the compression strength in the circumferential direction due to the Bauschinger effect when expanded and methods of production of the same, that is steel plate or steel pipe with small occurrence of the Bauschinger effect characterized by having a dual-phase structure substantially comprising a ferrite structure and fine martensite which is dispersed in the ferrite structure. Further, this steel plate or steel pipe contains, by mass %, C: 0.03 to 0.30%, Si: 0.01 to 0.8%, Mn: 0.3 to 2.5%, P: 0.03% or less, S: 0.01% or less, Al: 0.001 to 0.01%, and N: 0.01% or less and a balance of iron and unavoidable impurities.Type: ApplicationFiled: February 15, 2005Publication date: November 20, 2008Inventors: Hitoshi Asahi, Eiji Tsuru
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Publication number: 20080257008Abstract: The present invention provides a high strength welded steel pipe superior in weld zone embrittlement crack characteristics and a method of production of the same, that is, a method of production of a welded steel pipe superior in hydrogen embrittlement cracking resistance of weld metal characterized by seam welding from the inner and outer surfaces by a tensile strength of 850 MPa or more, then expanding or reducing the size of the pipe for correction, which method of production of welded steel pipe characterized in that the hydrogen concentration of the preceding weld metal is 0.2 cc or less per 100 g at ordinary temperature.Type: ApplicationFiled: February 22, 2006Publication date: October 23, 2008Inventors: Eiji Tsuru, Takuya Hara, Hitoshi Asahi, Hiroshi Morimoto, Yoshio Terada, Tatsuya Yoshida, Kouichi Shinada
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Patent number: 7431781Abstract: A common-rail injection system is provided for a diesel engine and has excellent internal pressure fatigue resisting characteristics, vibrational fatigue resisting characteristics and cavitation resisting property and sheet face flawing resisting property, and can be made thin and light in weight. A main pipe rail is manufactured by transformation induced plastic type strength steel. After the main pipe rail is processed, residual austenite is generated by heat treatment, and the reduction processing of stress concentration of a branch hole and a main pipe rail side flow passage crossing portion is performed. Further, it is preferable that an induced plastic transformation is generated on the inner surface of the main pipe rail by autofrettage processing, and compression residual stress is left.Type: GrantFiled: September 15, 2005Date of Patent: October 7, 2008Assignee: USUI Kokusai Sangyo Kaisha LimitedInventors: Masayoshi Usui, Kikuo Asada, Teruhisa Takahashi
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Patent number: 7393420Abstract: Steel tubes for bearing element parts according to the present invention, wherein the specific compositions are limited and an accumulation intensity of {211} face along with an impact property at ambient temperature in the longitudinal direction of steel tube are specified, can be provided as a source material for bearing element parts, which have excellent machinability and fatigue life in rolling contact, being incorporated without adding a free-cutting element specifically nor without reducing productivity since the spheroidizing for the same annealing duration with that of conventional spheroidizing treatment can be applied. Accordingly, by applying a manufacturing method or a cutting-machining method according to the present invention, bearing element parts such as races, rollers and shafts can be produced with less cost and efficiently.Type: GrantFiled: July 29, 2005Date of Patent: July 1, 2008Assignee: Sumitomo Metal Industries, Ltd.Inventors: Yoshihiro Daito, Takashi Nakashima
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Patent number: 7238434Abstract: This invention relates to a welded line pipe structure for transporting corrosive petroleum or natural gas. It is constituted by martensitic stainless steel pipes containing 8–16% Cr and at most 0.05% C. By suitably controlling the welding conditions at the time of girth welding of the steel pipes so as to ensure that the Cr concentration in grain boundary Cr-depleted portions existing immediately beneath a weld oxide scale is at least 5%, the occurrence of SCC in a high temperature CO2 environment can be prevented.Type: GrantFiled: March 3, 2006Date of Patent: July 3, 2007Assignee: Sumitomo Metal Industries, Ltd.Inventors: Hisashi Amaya, Kazuhiro Ogawa, Kunio Kondo, Masayuki Sagara, Hiroyuki Hirata
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Patent number: 7169239Abstract: A very low carbon steel alloy is provided for use in manufacturing tubular members such as oil country tubular goods. The tubular members may be radially expanded from at least twenty percent to forty percent. Sections or joints of casing formed from the steel alloy may be installed within a wellbore and radially expanded during completion of the wellbore.Type: GrantFiled: May 16, 2003Date of Patent: January 30, 2007Assignee: Lone Star Steel Company, L.P.Inventors: Gary M. Reavis, Bluford W. Lowery, Ralph R. Myers, Bowman A. Urech
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Patent number: 7060951Abstract: To set the length of a rotary tool (1a), to be thermally shrunk in place in a tool holder (7a), by means of an inductive heating device (15a), a setting device is provided with a positioning holder (61) for the rotary tool (1a), this positioning holder (61) being freely displaceable, but lockable, along a guide (35a) and its tool push-in movement into the thermally expanded tool holder (7a) being limited by a stop (71). The rotary tool (1a) bears with its tip (31a) against a stop (43a) of the positioning holder (61). By means of a length-measuring device (39a), the stop (71) limiting the push-in movement can be limited to a position in which the tip (31a) of the rotary tool (1a) is at a predetermined distance from a reference surface (33a) of a holder receptacle (17a), holding the tool holder (7a) during the shrink-fitting operation, or from a corresponding reference surface of the tool holder (7a).Type: GrantFiled: April 26, 2005Date of Patent: June 13, 2006Assignee: Haimer GmbHInventors: Franz Haimer, Josef Haimer, Bernhard Regau
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Patent number: 6948649Abstract: The high yield ratio problem intrinsic in high-strength steel pipes is solved and a method of producing a steel pipe, while securing the pipe roundness is provided. A steel pipe produced from a steel plate by forming and welding is subjected to 0.3 to 1.2% of expansion and then to 0.1 to 1.0% of reduction. The steel pipe produced by this method has a structure in which martensite and/or bainite accounts for more than 80% as expressed in terms of area percentage, and has a yield strength of not lower than 551 MPa and a yield ratio of not higher than 93%. The pipe reduction is desirably carried out at a lower work ratio as compared with the pipe expansion.Type: GrantFiled: September 20, 2002Date of Patent: September 27, 2005Assignee: Sumitomo Metal Industries, Ltd.Inventors: Nobuaki Takahashi, Akio Yamamoto, Tomoaki Ikeda, Tetsuya Fukuba
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Patent number: 6887322Abstract: High pressure cylinders comprising backing steel cylinders and tool steel liners are disclosed. An annealed tool steel liner is inserted into the backing steel cylinder, followed by heat treating to harden the tool steel liner. The tool steel liner may be provided as a single continuous tube, thereby avoiding problems associated with segmented liners. The high-pressure cylinders are suitable for use as plastic and rubber extruders injection molding cylinders and the like.Type: GrantFiled: April 9, 2002Date of Patent: May 3, 2005Assignee: Wexco CorporationInventors: Donald W. Smith, Calvin D. Lundeen
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Patent number: 6866725Abstract: The present invention is a high strength steel pipe excellent in formability in hydroforming and similar forming methods, characterized by: containing, in mass, C of 0.0005 to 0.30%, Si of 0.001 to 2.0%, Mn of 0.01 to 3.0% and appropriate amounts of other elements if necessary, with the balance consisting of Fe and unavoidable impurities; and an average for the ratios of the X-ray strength in the orientation component group of {110}<110> to {111}<110> to random X-ray diffraction strength on a plane at the wall thickness center being 2.0 or more and/or a ratio of the X-ray strength in the orientation component of {110}<110> to random X-ray diffraction strength on the plane at the wall thickness center being 3.0 or more.Type: GrantFiled: February 28, 2001Date of Patent: March 15, 2005Assignee: Nippon Steel CorporationInventors: Nobuhiro Fujita, Naoki Yoshinaga, Manabu Takahashi, Hitoshi Asahi, Yasuhiro Shinohara, Yasushi Hasegawa
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Patent number: 6780261Abstract: A metallurgical process for producing a metallic implantable medical device, such as a stent, in a condition wherein the metallic alloy of the device has improved mechanical properties. The starting material is formed into an oversized tube which is drawn to finished outer diameter. The drawing process cold works the tube to produce a material having a high dislocation density and a yield strength that is above approximately 125 ksi. Next, the drawn tube is heat treated at a temperature of approximately one-half the absolute melting temperature of the alloy. The heat treatment causes dislocations to rearrange, forming sub-grains and re-crystallization of the grain structure. Upon cooling, a material is obtained having a yield strength between approximately 45-70 ksi and an elongation exceeding 40 percent. The material also has good resistance to fatigue fracture due to the fine grains and sub-grains that are established during the heat treatment.Type: GrantFiled: June 27, 2002Date of Patent: August 24, 2004Assignee: SciMed Life Systems, Inc.Inventor: Thomas Trozera
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Patent number: 6749894Abstract: A method of providing a protective, corrosion-resistant thin coating of a MCrX alloy on a carbon or low-alloy steel pipe or tube where M is one of nickel, cobalt or iron or combination thereof and X is one of molybdenum, silicon, tungsten or combination thereof, and heat treating the coating to metallurgically bond the coating onto a steel substrate of the pipe or tube. The coating may be deposited in one or two layers by plasma transferred arc deposition or may be deposited as a slurry coating or thermal spray coating with sintering of the coating. The steel substrate is prepared for coating by at least one of boring, honing, bright finishing, grit blasting, grinding, chemical pickling or electro-polishing of the substrate.Type: GrantFiled: June 28, 2002Date of Patent: June 15, 2004Assignee: Surface Engineered Products CorporationInventors: Chinnia Gounder Subramanian, David Aaron Easton, Konstantin K. Tzatzov, Alexander S. Gorodetsky, Andrew George Wysiekierski
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Patent number: 6749954Abstract: 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: GrantFiled: May 31, 2002Date of Patent: June 15, 2004Assignee: JFE Steel CorporationInventors: Takaaki Toyooka, Masatoshi Aratani, Yoshikazu Kawabata, Yuji Hashimoto, Akira Yorifuji, Takatoshi Okabe, Takuya Nagahama, Mitsuo Kimura
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Patent number: 6723453Abstract: 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: GrantFiled: May 31, 2002Date of Patent: April 20, 2004Assignee: JFE Steel CorporationInventors: Takaaki Toyooka, Masatoshi Aratani, Yoshikazu Kawabata, Yuji Hashimoto, Akira Yorifuji, Takatoshi Okabe, Takuya Nagahama, Mitsuo Kimura
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Patent number: 6682610Abstract: A manufacturing method for a hollow stabilizer comprises a primary pipe manufacturing process for subjecting a seam-welded pipe to hot reduction working, thereby obtaining a primary pipe, and winding the primary pipe in a coil, a cold drawing process for subjecting the primary pipe to cold drawing so that the rate of reduction in area is not lower than 30%, thereby obtaining a thick-walled pipe having a wall thickness ratio of 0.20 to 0.27 higher than that of the seam-welded pipe and tensile strength of 800 N/mm2 to 1,000 N/mm2 is obtained, an internal shot peening process to be carried out as required, a bending process for bending the thick-walled pipe into a desired stabilizer shape in a cold state, an annealing process for subjecting the pipe to stress relieving annealing at a temperature of 300° C. to 450° C., after the bending process, and a shot peening process for shot-peening the annealed pipe.Type: GrantFiled: February 10, 2000Date of Patent: January 27, 2004Assignee: NHK Spring Co., Ltd.Inventor: Kanji Inoue
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Patent number: 6682829Abstract: A welded steel pipe is formed by heating or soaking an untreated welded steel pipe having a steel composition comprising, on the basis of mass percent: about 0.05% to about 0.3% C; about 2.0% or less of Si; more than about 1.5% to about 5.0% Mn; about 0.1% or less of P; about 0.01% or less of S; about 0.1% or less of Cr; about 0.1% or less of Al; about 0.1% or less of Nb; about 0.3% or less of Ti; and about 0.01% or less of N; and by diameter-reduction-rolling the treated steel pipe at a accumulated diameter reduction rate of at least about 35% and a finish rolling temperature of about 500° C. to about 900° C. The welded steel pipe exhibits excellent hydroformability, i.e., has a tensile strength of about 780 MPa or more and a n×r product of at least about 0.15. The treated steel pipe is preferably diameter-reduction-rolled at a accumulated diameter reduction rate of at least about 20% below the Ar3 transformation point.Type: GrantFiled: May 31, 2002Date of Patent: January 27, 2004Assignee: JFE Steel CorporationInventors: Takaaki Toyooka, Masatoshi Aratani, Yoshikazu Kawabata, Yuji Hashimoto, Akira Yorifuji, Takatoshi Okabe, Takuya Nagahama, Mitsuo Kimura
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Publication number: 20040012321Abstract: An Fe—Ni alloy material for a shadow mask having, in terms of % by weight, 34.0 to 38.0% of Ni, 0.05 to 0.45% of Cu, 0.10 to 0.50% of a combined total for Mn and Cu, no more than 0.10% of Si and 0.0004 to 0.005% of S with the balance being Fe and other unavoidable impurities; wherein a total count of MnS precipitates and Cu—S type precipitates having a diameter of 0.01 to 3 &mgr;m located on the surface of a foil strip 0.05 to 0.3 mm thick being at least 2,000 count/mm2.Type: ApplicationFiled: July 15, 2003Publication date: January 22, 2004Applicants: NIPPON MINING METALS CO LTD, JAPAN STEEL WORKS CO LTDInventors: Ikuya Kurosaki, Takashi Shibata, Shinji Tanaka
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Patent number: 6652680Abstract: The method for producing tubes for heavy guns employs a heat-treatable steel, consisting in wt.-% of 0.20 to 0.50% carbon, max. 1.0% silicon, max. 1.0% manganese, max. 0.03% phosphorus, max. 0.03% sulfur, max. 0.1% aluminum, max. 4% nickel, max. 2% chromium, max. 1% molybdenum, max. 0.5% vanadium, and the remainder of iron and the customary impurities. Forgings of open-smelted cast ingots are pre-worked on a lathe on the outside. The solid blanks obtained in this way are hardened and tempered, only subsequently drilled and then finished.Type: GrantFiled: March 8, 2002Date of Patent: November 25, 2003Assignees: Edelstahlwerke Buderus AG, Rheinmetall W & M GmbHInventors: Walter Grimm, Wolfgang Arrenbrecht
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Publication number: 20030196734Abstract: A method for manufacturing a seamless steel tube, wherein a tubing material for the seamless steel tube is produced by a hot working process from a material having less workability, such as a high Cr-high Ni-high C alloy steel including Cr at a content not less than 15 weight % and Ni at a content not less than 20 weight % or a ferritic stainless steel including Cr at a content not less than 16 weight %, and then cold drawn at a reduction rate of not less than 15% and further cold rolled after applying an appropriate heat treatment, so that a round or an inner grooved steel tube is obtained. It is preferable that the hot extrusion process is employed for the hot working process and a cold Pilger mill is employed for the cold rolling process. In the cold rolling process, the crackings or damage resulting from the reduced toughness of the tubing material as well as the breakage of a mandrel in producing the round or the inner grooved tube can be suppressed.Type: ApplicationFiled: April 16, 2003Publication date: October 23, 2003Inventor: Hidenori Ogawa
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Patent number: 6632296Abstract: The present invention provides a steel pipe excellent in formability during hydraulic forming and the like and a method to produce the same, and more specifically: a steel pipe excellent in formability having an r-value of 1.4 or larger in the axial direction of the steel pipe, and the property that the average of the ratios of the X-ray intensity in the orientation component group of {110}<110> to {332}<110> on the plane at the center of the steel pipe wall thickness to the random X-ray intensity is 3.5 or larger, and/or the ratio of the X-ray intensity in the orientation component of {110}<110> on the plane at the center of the steel pipe wall thickness to the random X-ray intensity is 5.Type: GrantFiled: February 6, 2002Date of Patent: October 14, 2003Assignee: Nippon Steel CorporationInventors: Naoki Yoshinaga, Nobuhiro Fujita, Manabu Takahashi, Yasuhiro Shinohara, Tohru Yoshida, Natsuko Sugiura
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Patent number: 6589373Abstract: A selectively heat treated canister for use in a vehicle airbag deployment system is configured to contain combustion materials and to contain gases produced from the combustion thereof. The canister includes a tubular body having a length and a longitudinal axis. The body is formed as at least three drawn sections. Each prior section is drawn one more time than a successive adjacent section. The canister defines a closed end and an open end. The closed end is at a least drawn section and the open end is at a most drawn section. The canister defines a heat treated region and is selectively heat treated at least one transition zone between adjacent drawn sections to reduce crack propagation observed during testing. A method for making the canister is also disclosed.Type: GrantFiled: October 2, 2001Date of Patent: July 8, 2003Assignee: Illinois Tool Works, Inc.Inventors: Michael Starozhitsky, Matthew J. Reiter
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Patent number: 6565682Abstract: An object is to provide a heat-resistant steel which can be produced at a low cost but possesses an excellent high-temperature strength. A high-strength heat-resistant steel is provided which comprises C in an amount of 0.06 to 0.15% by weight, Si in an amount of 1.5% by weight or less, Mn in an amount of 0.5 to 1.5% by weight, V in an amount of 0.05 to 0.3% by weight, and at least one of Nb, Ti, Ta, Hf, and Zr, in an amount of 0.01 to 0.1% by weight, the balance being Fe and unavoidable impurities, wherein the high-strength heat-resistant steel has a structure consisting mainly of a bainite structure.Type: GrantFiled: August 3, 2001Date of Patent: May 20, 2003Assignee: Mitsubishi Heavy Industries, Ltd.Inventors: Nobuhiko Nishimura, Masahiro Umata, Masashi Ozaki
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Patent number: 6475307Abstract: A composition and method for the manufacture of products of a precipitation hardenable martensitic stainless steel, the composition of which comprises at least 0.5% by weight of Cr and at least 0.5% by weight of Mo wherein the sum of Cr, Ni and Fe exceeds 50%. The method steps include smelting the material into a casting, hot extrusion followed by a number of cold deforming steps so as to obtain at least 50% martensite and finally an ageing treatment at 425-525° C. to obtain precipitation of quasicrystalline particles. Such material can be used in vehicle components where demands for corrosion resistance, high strength and good toughness are to be satisfied.Type: GrantFiled: November 16, 2000Date of Patent: November 5, 2002Assignee: Sandvik ABInventors: Anna-Lena Nyström, Anna Hultin Stigenberg
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Publication number: 20020007871Abstract: An object is to provide a heat-resistant steel which can be produced at a low cost but possesses an excellent high-temperature strength. A high-strength heat-resistant steel is provided which comprises C in an amount of 0.06 to 0.15% by weight, Si in an amount of 1.5% by weight or less, Mn in an amount of 0.5 to 1.5% by weight, V in an amount of 0.05 to 0.3% by weight, and at least one of Nb, Ti, Ta, Hf, and Zr, in an amount of 0.01 to 0.1% by weight, the balance being Fe and unavoidable impurities, wherein the high-strength heat-resistant steel has a structure consisting mainly of a bainite structure.Type: ApplicationFiled: August 3, 2001Publication date: January 24, 2002Applicant: MITSUBISHI HEAVY INDUSTRIES, LTD.Inventors: Nobuhiko Nishimura, Masahiro Umata, Masashi Ozaki
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Patent number: 6302974Abstract: An austenitic rounding fixture is inserted into the horizontal joint of a turbine casing. The casing is then assembled and stress relief cycle is carried out, resulting in rerounding of the casing and relief of residual stresses. Since an austenitic material has a higher thermal expansion coefficient than the metallic materials of conventional turbine casings, the rounding fixtures expand more than the casing during a stress relief cycle. The length of the fixtures are designed in such a way that at stress relief temperature the casing is slightly over-rounded. After the stress relief, the casing is rerounded and the austenitic rounding Fixtures is disengaged. The rounding fixture is installed in a cold condition (or with minimal heat for heavily collapsed casings). The removal of the rounding fixtures is easy since a clearance exists between the casing and the fixtures; the spring back of the casing is far less then the contraction of the fixtures.Type: GrantFiled: April 23, 1999Date of Patent: October 16, 2001Assignee: ABB Power GenerationInventors: Peter L. Wilhelm, Bruno Stoeckli
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Patent number: 6270596Abstract: Disclosed is a process for producing a shaft having improved strength without sacrificing machinability and cold workability. The process for producing a high strength shaft comprises the steps of: rolling or forging an alloy at a heating temperature of Ac3 to 105° C. with a reduction in area of not less than 30%, the alloy comprising by weight carbon: 0.47 to 0.55%, silicon: 0.03 to 0.15%, manganese: 0.20 to 0.50%, molybdenum: 0.08 to 0.30%, sulfur: 0.005 to 0.035%, boron: 0.0005 to 0.005%, titanium: 0.05 to 0.20%, nitrogen: not more than 0.01%, aluminum: 0.005 to 0.05%, and manganese+molybdenum: 0.45 to 0.70% with the balance consisting of iron and unavoidable impurities, thereby producing a steel product having a hardness after rolling or forging of 85 to 97 HRB; and induction hardening the steel product to obtain a shaft, as shown in FIG. 1, having a hardening depth ratio (distance from the surface to a position of 500 HV/radius of component) of not less than 0.Type: GrantFiled: October 15, 1999Date of Patent: August 7, 2001Assignees: Sanyo Special Steel., Ltd., Honda Motor Co., Ltd.Inventors: Makoto Iguchi, Motohiro Nishikawa, Masayoshi Saga
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Patent number: 6261392Abstract: The invention concerns a method for manufacturing quenched metal hollow casings of steel by blow-moulding whereby a preheated hollow casing billet, preferably above austenitising temperature, is introduced into a blow-moulding tool (1) and moulded by being expanded against the inner walls of the tool by the introduction of a preheated, pressurized medium into the interior cavity of the hollow casing, whereby the moulded hollow casing (6) is rapidly cooled in a process adapted to obtain quenching of the steel material by the dominating heated medium in the hollow casing being replaced by a pressurized cooling medium and that a cooling medium is led through the moulding tool to achieve its cooling.Type: GrantFiled: March 20, 2000Date of Patent: July 17, 2001Assignee: Accra Teknik ABInventors: Anders Sundgren, Mats Lindberg, Göran Berglund
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Patent number: 6220306Abstract: A hot rolled martensite stainless steel plate which is excellent in formability and corrosion resistance has a chemical composition comprising, by mass %, 0.05% or less carbon, 10 to 15% chromium, 0 to 3% molybdenum, 0 to 0.75% titanium, and 1 to 8% nickel, with the balance being iron and impurities, and has a yield stress of 110 ksi (758 MPa) or less and a specific amount of austenitic phase according to the plate thickness.Type: GrantFiled: November 23, 1999Date of Patent: April 24, 2001Inventors: Tomohiko Omura, Takahiro Kushida
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Patent number: 6217676Abstract: A steel for oil well pipe, which has excellent resistance to localized corrosion in CO2 environments and corrosion in seawater, and a seamless pipe made of the steel. The steel includes, in weight %, more than 0.10 to 0.30% C, 0.10 to 1.0% Si, 0.1 to 3.0% Mn, 2.0 to 9.0% Cr, 0.01 to 0.10% Al and optionally 0.05 to 0.5% Cu, and the balance including Fe and incidental impurities including not more than 0.03% P and not more than 0.01% S. The steel has a substantially single phase martensitic structure in the as-quenched or as-normalized condition, and yield strength of not lower than 552 MPa in the as-quenched-tempered or as-normalized-tempered condition.Type: GrantFiled: May 27, 1999Date of Patent: April 17, 2001Assignee: Sumitomo Metal Industries, Ltd.Inventors: Hideki Takabe, Masakatsu Ueda
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Patent number: 6193820Abstract: A method for the thermal treatment of bushings, particularly for tracked vehicles and the like, which provides for a first step, during which external quench hardening of the bushing is performed by heating through to approximately {fraction (7/10-10/10)} of the thickness of the bushing, followed by cooling with quenching liquid; then a second step for internal quench hardening is performed by heating the bushing through to approximately {fraction (4/10-7/10)} of the thickness thereof and then cooling with quenching liquid; the method ends by performing a step for the stress relieving of the bushing. A product at low costs can thus be obtained which has better wear resistance and fatigue strength than observed in bushings obtained with conventional methods.Type: GrantFiled: October 27, 1997Date of Patent: February 27, 2001Inventors: Bruno Girardello, Pierangelo Girardello, Giampaolo Girardello
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Patent number: 6090230Abstract: A method of cooling a martensitic steel pipe by cooling the inner and outer surface substantially equally while rotating the pipe around the axis, wherein the cooling rate is 8.degree. C./s or higher. The inner surface is preferably cooled by passing water without completely filling the inside of pipe. The maximum cooling rate at the both surfaces is 35.degree. C./s or lower for a martensitic stainless steel pipe. The 2-step cooling method of a martensitic stainless steel pipe, comprising the 1st air cooling where the pipe is cooled from 30.degree. C. lower than Ms(martensitic transformation start temp.) to the average of Ms and Mf(martensitic transformation finish temp.) and 2nd intensive water cooling where the the pipe is cooled down below Mf. The 3-step cooling method comprising 1st intensive cooling where the pipe is cooled from Ms+400.degree. C. to Ms, 2nd mild cooling where the pipe is cooled from Ms to the average of Ms and Mf, and 3rd intensive cooling to the Mf.Type: GrantFiled: May 30, 1997Date of Patent: July 18, 2000Assignee: Sumitomo Metal Industries, Ltd.Inventors: Kazuo Okamura, Naruhito Shouji, Michiharu Hariki, Kunio Kondo
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Patent number: 5730812Abstract: A method is disclosed for manufacturing ejector sleeves from tubular stock. In particular, the method includes the following steps or operations: (a) cutting the tube stock to length, (b) enlarging a portion of the inside diameter of the sleeve to provide a clearance diameter, (c) rough-sizing a close-fitting inner diameter, (d) optionally semi-finishing the outside diameter of the sleeve, (e) hardening and straightening the sleeve, (f) final sizing of the outside diameter while maintaining concentricity with the inside diameters, (g) finishing the end face of the sleeve adjacent the close-fitting diameter, (h) final sizing of the close-fitting inner diameter while maintaining concentricity with the outside diameter, (i) forming a head on the sleeve by heating and forging to a predetermined size, (j) optional annealing and refinishing of the head for purposes of hardness or dimensional modification, or improving surface finish.Type: GrantFiled: May 19, 1997Date of Patent: March 24, 1998Assignee: D-M-E CompanyInventor: David E. Lawrence
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Patent number: 5605587Abstract: Martensitic steel components of apparatus for magnetic conditioning of liquids which are subjected to cathodic reaction and degradation are treated prior to use to form a barrier of iron-chromium oxide and a uniform level of hardness throughout by heating the steel to a temperature near the grain boundary temperature of the steel, maintaining that temperature for a specified period and then rapidly quenching the steel.Type: GrantFiled: April 7, 1995Date of Patent: February 25, 1997Assignee: Hydrodynamics CorporationInventor: John H. Meckling
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Patent number: 5454855Abstract: A compacted and consolidated material of an aluminum-based alloy obtained by compacting and consolidating a rapidly solidified material having a composition represented by the general formula: Al.sub.a Ni.sub.b X.sub.c M.sub.d, Al.sub.a Ni.sub.b X.sub.c Q.sub.e or Al.sub.a 'Ni.sub.b X.sub.c M.sub.d Q.sub.e, wherein X represents at least one element selected from the group consisting of La, Ce, Mm (misch metal), Ti and Zr; M represents at least one element selected from the group consisting of V, Cr, Mn, Fe, Co, Y, Nb, Mo, Hf, Ta and W; Q represents at least one element selected from the group consisting of Mg, Si, Cu and Zn; and a, a', b, c, d and e are, in atomic percentages, 85.ltoreq.a.ltoreq.94.4, 83.ltoreq.a.ltoreq.94.3, 5.ltoreq.b.ltoreq.10, 0.5.ltoreq.c.ltoreq.3, 0.1.ltoreq.d.ltoreq.2 and 0.1.ltoreq.e.ltoreq.2.Type: GrantFiled: October 27, 1992Date of Patent: October 3, 1995Assignee: YKK CorporationInventors: Kazuhiko Kita, Hidenobu Nagahama, Takeshi Terabayashi, Makoto Kawanishi
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Patent number: 5405459Abstract: A production process for producing a hollow steel tube of a high strength includes the steps of a tube preparation step of producing a seamless steel tube of a heavy thickness containing flaws of less than 0.25 mm in depth in an inner periphery thereof, a tube inner periphery correction step of correcting at least the flaws having a width of 0.001 mm or less so as to have a depth of 0.15 mm or less, and a hardening step of hardening the seamless steel tube across a whole thickness thereof to a hardness of from 450 to 670 in Vickers hardness (Hv). The production process enables not only to produce a hollow steel tube of a high strength at a less production cost but also to adapt it to exhibit such a high torsional fatigue fracture resistance and a high impact strength that it is applicable to axles for large size automobiles producing high outputs.Type: GrantFiled: October 18, 1993Date of Patent: April 11, 1995Assignee: Toyota Jidosha Kabushiki KaishaInventors: Noritaka Miyamoto, Masazumi Onishi
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Patent number: 5215829Abstract: A method for strengthening a pressure resistant property of a hollowed structure made of a metallic material and a pressure resistant hollowed structure made by such method. The method includes providing a temperature differential in a thickness direction between an outer side and an inner side of the metallic material with an arranged sufficient to generate a stress not exceeding a yielding stress of the metallic material. The outer side and inner side are pressurized so as to superimposed a stress generated by the pressurizing and the stress caused by the temperature differential reaching the yielding stress of the metallic material. The pressure is released subsequent to the superimposed stress reaching a level of the yielding stress of the metallic material.Type: GrantFiled: January 24, 1991Date of Patent: June 1, 1993Assignee: Hitachi, Ltd.Inventors: Takashi Matsunobu, Kenzi Aizawa, Kazumi Anazawa, Kunio Enomoto
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Patent number: 5173133Abstract: An anvil member for use in a surgical stapler is annealed by localized heating, preferably induction heating. A shaped shielding means is used to cradle the anvil so as to expose the staple crimping portion of the anvil. The heating is performed so as to anneal only the delimited staple crimping portion of the anvil. All other portions of the anvil are either shielded by the cradle or are out of the heating range.Type: GrantFiled: July 23, 1991Date of Patent: December 22, 1992Assignee: United States Surgical CorporationInventors: Donald A. Morin, Bartolo Sciano, Jr.
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Patent number: 4750947Abstract: The surface of a base metal is alloyed with the aid of a laser or electron beam which locally melts the surface. During the alloying, defects are prevented from occurring due to the use of an deoxidizing agent and a low-melting-point metal having a lower melting point than than of the base metal.Type: GrantFiled: March 19, 1987Date of Patent: June 14, 1988Assignee: Nippon Steel CorporationInventors: Seishiro Yoshiwara, Takao Kawanami