EP2028284B1 - High-strength seamless steel pipe for mechanical structure which has excellent toughness and weldability, and method for manufacture thereof - Google Patents

High-strength seamless steel pipe for mechanical structure which has excellent toughness and weldability, and method for manufacture thereof Download PDF

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Publication number
EP2028284B1
EP2028284B1 EP07740796A EP07740796A EP2028284B1 EP 2028284 B1 EP2028284 B1 EP 2028284B1 EP 07740796 A EP07740796 A EP 07740796A EP 07740796 A EP07740796 A EP 07740796A EP 2028284 B1 EP2028284 B1 EP 2028284B1
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European Patent Office
Prior art keywords
steel pipe
toughness
less
cooling
weldability
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Expired - Fee Related
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EP07740796A
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German (de)
English (en)
French (fr)
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EP2028284A1 (en
EP2028284A4 (en
Inventor
Yasuhiro Shinohara
Tetsuo Ishitsuka
Kazuhiro Inoue
Bunshi Kato
Teruhisa Takamoto
Junichi Okamoto
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Nippon Steel Corp
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Nippon Steel Corp
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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B23/00—Tube-rolling not restricted to methods provided for in only one of groups B21B17/00, B21B19/00, B21B21/00, e.g. combined processes planetary tube rolling, auxiliary arrangements, e.g. lubricating, special tube blanks, continuous casting combined with tube rolling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/18—Hardening; Quenching with or without subsequent tempering
    • C21D1/25—Hardening, combined with annealing between 300 degrees Celsius and 600 degrees Celsius, i.e. heat refining ("Vergüten")
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/10—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of tubular bodies
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/08—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for tubular bodies or pipes
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/002—Bainite
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/008—Martensite

Definitions

  • the present invention relates to seamless steel pipe suitable for machine structural members, in particular cylinders, bushing, booms, and other structural members and shafts and other machine members and a method of production of the same.
  • steel pipe is more expensive than steel bars.
  • seamless steel pipe is high in production costs, so even if using steel pipe as a material for hollow shaped articles, the effect in reducing costs sometimes cannot be said to be sufficient.
  • Japanese Patent Publication (A) No. 5-202447 Japanese Patent Publication (A) No. 10-130783
  • Japanese Patent Publication (A) No. 10-204571 Japanese Patent Publication (A) No. 10-324946
  • Japanese Patent Publication (A) No. 11-36017 Japanese Patent Publication (A) No. 2004-292857 all are high in amount of C and have large amounts of carbonitride-forming elements added to improve the hardenability and precipitation strengthening ability and obtain a predetermined strength.
  • Japanese Patent No. 3503211 and Japanese Patent Publication (A) No. 7-41856 disclose the method described in Japanese Patent No. 3503211.
  • the method described in Japanese Patent No. 3503211 allows the inner surface of the steel pipe after final finishing rolling to cool, cools the outer surface from a temperature of the Ar 3 point or more to 500 to 400°C by 10 to 60°C/s, then allows it to gradually cool.
  • the method described in Japanese Patent Publication (A) No. 7-41856 comprises direct quenching or accelerated cooling as hot rolled.
  • WO 99/05 336 discloses a pipe containing 0.01-0.1 Vanadium and made by the U-O-E process.
  • the present invention was made in consideration of the above situation.
  • it provides seamless steel pipe suitable for machine structural member use for cylinders, bushings, booms, or other structural members and shafts or other machine members where high strength, high toughness, and weldability are required and provides a method for inexpensively producing that steel pipe without tempering.
  • the inventors studied combinations of chemical ingredients and the cooling rate and stop temperature of accelerated cooling for producing the optimum structure enabling achievement of both high strength and high toughness across the entire surface in the plate thickness direction even in an environment where differences occur in the cooling rate at the outside surface and inside surface due to accelerated cooling only from the outside surface.
  • the inventors first studied the metallurgical structure and form of cementite of a seamless steel pipe or machine structural use produced by the prior art quenching and tempering and the effect on the strength and toughness and obtained the following discovery.
  • tempered martensite structure When using quenching-tempering to produce steel pipe, cementite precipitates in the matrix at the time of quenching and the residual austenite breaks down into cementite and ferrite at the time of tempering.
  • the thus obtained tempered martensite structure has cementite of an average particle size of 500 nm or more and is inferior in the balance of strength and toughness (below, called the "strength-toughness balance").
  • the inventors postulated a process of production of seamless steel pipe by accelerated cooling without tempering and studied metallurgical structures for improving both the strength and toughness and production conditions for obtaining the same.
  • the inventors investigated in detail the relationship between the form of cementite and the strength and toughness and as a result learned that if the average particle size is 400 nm or less and the density is 2 ⁇ 10 5 /mm 2 or more, an extremely good strength-toughness balance is obtained.
  • a crystal orientation map of steel having a single phase structure of self-tempered martensite or a mixed phase structure of self-tempered martensite and lower bainite is prepared by an electron back scattering pattern (EBSP) and the strength-toughness balance was investigated.
  • EBSP electron back scattering pattern
  • C is an element extremely effective in improving the strength. To obtain the target strength, at a minimum 0.03% is necessary. However, if containing 0.1% or more of C, the low temperature toughness remarkably falls and further the cracking at the time of welding becomes a problem. Therefore, C is limited to 0.03 to less than 0.1%.
  • Mn is an element essential for improving the balance of strength and low temperature toughness.
  • the lower limit is 0.8%. However, if greater than 2.5%, conversely the low temperature toughness greatly deteriorates, so 2.5% was made the upper limit.
  • Ti not only forms fine TiN and makes the structure finer, but also increase the hardenability and the toughness. If less than 0.005%, the effect is small, so the lower limit was made 0.005%. However, if greater than 0.035%, coarse TiN and TiC precipitate and the low temperature toughness remarkably falls, so the upper limit was made 0.035%.
  • Nb not only suppresses recrystallization of the austenite at the time of rolling and increases the fineness of the structure, but also increases the hardenability and increases the toughness of the steel. If less than 0.003%, the effect is small, so the lower limit was made 0.003%. However, if more than 0.04%, coarse Nb precipitates are formed and the toughness deteriorates, so the upper limit was made 0.04%.
  • B is an element increasing the hardenability and increasing the toughness.
  • the lower limit where the effect is obtained is 0.0003%.
  • the upper limit was made 0.003%.
  • the upper limits of the deoxidizing elements Si and Al and the impurities P, S, and N are as follows:
  • Ni, Cr, Cu, and Mo is added.
  • Ni is an element improving the strength. 0.1% or more is added. However, if over 1.5%, the element unevenly precipitates and the structure becomes uneven and the toughness sometimes deteriorates, so the upper limit is made 1.5%.
  • Cr Cr is an element improving the strength. 0.1% or more is added. However, if over 1.5%, conversely Cr precipitates are formed and the toughness sometimes deteriorates, so the upper limit is made 1.5%.
  • Cu is an element improving the strength. 0.1% or more is added. However, if over 1.0%, upper bainite is formed and the toughness is sometimes impaired. Further, the weldability sometimes deteriorates, so the upper limit is made 1.0%.
  • Mo is an element contributing to higher strength. To obtain the effect of improvement of the hardenability, 0.05% or more is added. However, if over 0.5%, the weldability is sometimes impaired, so the upper limit is made 0.5%.
  • the metallurgical structure of the steel of the present invention is a single phase structure of self-tempered martensite or a mixed phase structure of self-tempered martensite and lower bainite.
  • the self-tempered martensite and lower bainite are structures obtained by accelerated cooling. Due to these structures, it is possible to obtain an excellent balance of strength and toughness without tempering.
  • bainite transformation sometimes occur at the inside surface side of the steel pipe, but if lower bainite, a strength-toughness balance can be secured, so there is no particular problem.
  • lower bainite a strength-toughness balance can be secured, so there is no particular problem.
  • the metallurgical structure of the steel has to be a single phase structure of self-tempered martensite or a mixed phase structure of self-tempered martensite and lower bainite.
  • self-tempered martensite means the structure resulting from the austenite phase transforming to martensite during accelerated cooling and fine cementite precipitating in the laths by the gradual cooling after the accelerated cooling is stopped.
  • the structure obtained by normal tempering is tempered martensite. Compared with this, the cementite of self-tempered martensite is extremely fine.
  • lower bainite is defined as the structure resulting from lath type ferrite forming during accelerated cooling and fine cementite precipitating in one direction in the laths.
  • Self-tempered martensite and lower bainite are common in the points that there is no coarse cementite at the grain boundaries and there is fine cementite in the matrix.
  • Self-tempered martensite and lower bainite are both lath type states, but these can be differentiated by the state of precipitation of cementite in the laths. That is, there are several long axis directions of cementite in self-tempered martensite, while lower bainite has a single long axis direction of cementite.
  • Upper bainite is a structure resulting from acicular cementite or a martensite-austenite mixed structure formed at the lath boundaries. Ferrite is not lath shaped such as bainite, but is aggregate in form. Pearlite is comprised of plate shaped cementite precipitated at the grain boundaries.
  • Self-tempered martensite and lower bainite can be judged if using a scanning electron microscope (SEM) for observation by a power of 2000X to 50000X.
  • SEM scanning electron microscope
  • the sample should be mirror polished at its observed surface and etched by Nital.
  • the average particle size of areas surrounded by high angle boundaries with an orientation difference of 15° or more has an effect of propagation of cracks at the time of breakage. If the high angle boundary average size becomes 30 ⁇ m or more, the toughness falls, so from the viewpoint of the strength-toughness balance, the high angle boundary average size is 30 ⁇ m or less.
  • the higher angle boundary average size the better the strength-toughness balance, but with the current art, reduction to 3 ⁇ m or less is difficult.
  • the high angle boundary average size can be found from a crystal orientation map measured by EBSP.
  • the average particle size of the cementite is 400 nm or less. This is because if the average particle size of the cementite is over 400 nm, the toughness falls. The smaller the average particle size of the cementite, the better, but cementite finer than 30 nm is difficult to judge by SEM, so in the present invention, the upper limit of the average particle size of cementite with a particle size of 30 nm or more is prescribed as 400 nm.
  • the density of the cementite is 2 ⁇ 10 5 /mm 2 or more, there is almost no formation of coarse cementite and an extremely good strength-toughness balance can be obtained.
  • the upper limit of the density of the cementite is not particularly limited, but is determined by the amount of addition of C and average particle size.
  • the conditions when acceleratedly cooling steel pipe having the above chemical ingredients from a temperature of 750°C or more are important.
  • the cooling rate is that at a position of the inside surface of the steel pipe.
  • the accelerated cooling stop temperature is one root technology of the present invention. The reason is that this has a major effect on the precipitation behavior of cementite in the matrix - which is the most effective for improvement of the strength-toughness balance.
  • the lower limit was made less than 150°C: 150 ⁇ T ⁇ 821.34 ⁇ V - 0.3112
  • the range of the cooling rate in the accelerated cooling of the steel pipe will be explained. If the cooling rate is less than 5°C/s, upper bainite and ferrite are formed, while if over 50°C/s, uniform cooling becomes difficult and, after cooling, the steel pipe greatly deforms. Therefore, the accelerated cooling rate was limited to 5 to 50°C/s. Note that when the cooling rate is made that range, when the cooling rate is slow, lower bainite easily forms.
  • the reason for limiting the temperature for starting the accelerated cooling of the steel pipe to 750°C or more is to make the metal structure at the time of start of accelerated cooling an austenite single phase. If the temperature of the steel pipe when starting the accelerated cooling is too high, the austenite grains will become coarser and a drop in toughness will be invited, so the accelerated cooling start temperature is preferably 950°C or less.
  • the cooling start temperature and cooling stop temperature of the inside surface of the steel pipe should be measured before and after the accelerated cooling, that is, at the inlet side and outlet side of the cooling apparatus, by a contact thermometer at the inside surface of the steel pipe. It is possible to calculate the cooling rate from the temperature difference and the rate of passage through the cooling apparatus. It is also possible to measure the temperature of the outside surface of the steel pipe by a radiant thermometer and find the temperature of the inside surface of the steel pipe by calculation of the heat conduction.
  • thermocouples to the inside surface and the outside surface of steel pipes having various outside diameters and thicknesses, prepare cooling curves corresponding to various heating temperatures, refrigerant spraying conditions, and cooling times, and determine the conditions giving the range of the present invention.
  • the steel pipe of the present invention is seamless steel pipe.
  • the pipe-forming process is generally hot piercing, rolling, and elongation, but it is also possible to use cold machining for piercing, then heat the steel and produce the pipe by a hot extrusion press. Further, diameter reduction rolling is also possible.
  • the steel pipe may be raised in temperature by a heating furnace or induction heating. If the temperature of the steel pipe is 750°C or more after forming a steel billet into pipe by hot piercing, rolling, and elongation, accelerated cooling as is in-line is also possible.
  • the method of accelerated cooling is limited to the method of cooling from only the outside surface while rotating the steel pipe in the circumferential direction. Due to this, it is possible to uniformly cool the pipe across the circumferential direction and the longitudinal direction.
  • any of the method of bringing water into direct contact with the outside surface of the steel pipe, the method of bringing it into contact with the tangential direction of the outer circumference of the steel pipe, mist cooling, etc. may be selected.
  • the steel pipe shape which can be applied is preferably made a shape of a length of at least five times the outside diameter. This is because when the length is less than five times the outside diameter, when performing the accelerated cooling from the outside surface by water cooling, water penetrates to the inside surface of the steel pipe as well resulting in uneven cooling and bending of the steel pipe.
  • the length of the steel pipe is preferably made at least 10 times the outside diameter.
  • outside diameter 126 mm and thickness 12.2 mm small (S)
  • outside diameter 138 mm and thickness 16.4 mm medium (M)
  • outside diameter 146 mm and thickness 20.6 mm large (L)
  • the length was 6.5 m in each case.
  • Test pieces were taken from the produced steel pipes at any positions of the circumferential direction, longitudinal direction, and thickness direction, buried in resin, mirror polished and etched, then observed for structure by an SEM at a maximum power of 50000X.
  • the structures were classified into self tempered martensite (M), lower bainite (LB), upper bainite (UB), and ferrite (F).
  • the metallurgical structure was observed by an optical structure and measured for Vicker's hardness at 10 kgf based on JIS Z 2244.
  • each sample buried in resin was electrolytically polished.
  • the crystal orientation was measured.
  • the grain boundaries having orientation differences of 15° or more were identified, the average value of the circle equivalent radius of the area surrounded by the grain boundaries was found by image analysis, and the result was indicated in the column of high angle boundary average size of Table 2.
  • a tensile test was performed using a No. 11 test piece of JIS Z 2201 based on JIS Z 2241 to measure the yield strength and tensile strength.
  • the toughness was evaluated by running a Charpy impact test based on JIS Z 2242 using a 2 mmV notch full size test piece at -40°C and measuring the absorption energy (vE -40 (J)).
  • the weldability was evaluated by welding steel pipes together at room temperature using welding wire having a 780 MPa class strength by CO 2 gas welding to prepare steel pipe joints, inspecting for the presence of cracks by visual inspection after 24 hours, then judging ones with no cracks as passing.
  • the maximum rise of the end of the steel pipe is the height of the bottommost part of the raised end of the steel pipe from the flat plate.
  • Steel pipes with a maximum rise of the end of not more than 10 mm were judged as passing in steel pipe shapes.
  • Table 1 Steel type Chemical ingredients (mass%) Remarks C Si Mn P S Al Ti Nb N B Ni Cr Cu Mo A 0.060 0.13 2.00 0.008 0.003 0.029 0.012 0.021 0.0057 0.0011 0.45 0.30 Inv.ex. B 0.090 0.13 1.50 0.015 0.005 0.043 0.025 0.017 0.0023 0.0015 0.30 0.20 0.40 Inv.ex.
  • the results are shown in Table 2.
  • the underlines in Table 2 mean outside the range of the present invention or outside the preferable range.
  • the invention examples of No. 1 to 13 are steel pipes produced under suitable accelerated cooling conditions and are provided with suitable metal structures and the strength and toughness required as machine structural use steel pipes.
  • No. 14 is an example which was high in amount of C, amount of B, and amount of Ni and was high in accelerated cooling stop temperature, so an upper bainite structure was formed, the toughness fell, and the weldability fell.
  • No. 15 is an example which was too low in amount of C, insufficient in hardenability, and high in accelerated cooling stop temperature, so a partial upper bainite structure formed, the toughness fell, and the cooling rate was fast, so the shape also deteriorated.
  • No. 16 is an example where the amount of P was particularly high and the accelerated cooling start temperature was low, so ferrite was formed and the toughness fell.
  • No. 17 is an example where the amount of Si was too high, upper bainite was formed, and the toughness became poor.
  • No. 18 is an example where the amount of N, amount of Cu, and amount of S were too high and the cooling rate was slow, so upper bainite was formed, the toughness was impaired, and the weldability dropped.
  • No. 19 is an example where the amount of Al and amount of Nb were too high and the accelerated cooling stop temperature was high, so upper bainite was formed and the toughness was impaired and where Al was excessively included, so the weldability was also poor.
  • Nos. 21 and 25 were examples which were too high in accelerated cooling stop temperature, so upper bainite was formed and the toughness fell.
  • Nos. 22 and 24 are examples where the cooling rate is too fast and the accelerated cooling stop temperature was high, so a mixed structure of tempered martensite and upper bainite resulted, the toughness was low, and the shape was also poor.
  • No. 23 is an example where the accelerated cooling start temperature was too low and ferrite was formed, so the toughness was poor.
  • Table 2 No. Steel type Size Process Accelerated cooling start temperature (°C) Cooling rate V (°C/s) Accelerated cooling stop temperature (°C) 821.34 ⁇ V -0.3112 Metal structure Mechanical properties Weldability Shape of steel pipe Remarks Class High angle boundary average size ( ⁇ m) Cementite average particle size (nm) Cementite particles ⁇ 10 5 (/mm 2 ) Tensile strength (MPa) Yield strength (MPa) vE -40 (J) 1 A S Direct feed 949 33.9 207 274 M 20.7 142 5.5 972 785 265 Good Good Inv.ex.
  • the present invention it becomes possible to provide a high strength seamless steel pipe for machine structure use superior in toughness and weldability suitable for a machine structural member, in particular, a cylinder, bushing, boom, or other structural member and shaft or other machine member and a method inexpensively producing the steel pipe. Therefore, the present invention contributes to industry extremely remarkably.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
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Abstract

質量％で、Ｃ　：０．０３～０．１％未満、Ｍｎ：０．８～２．５％、Ｔｉ：０．００５～０．０３５％、Ｎｂ：０．００３～０．０４％、Ｂ　：０．０００３～０．００３％を含有し、Ｓｉ：０．５％以下、Ａｌ：０．０５％以下、Ｐ　：０．０１５％以下、Ｓ　：０．００８％以下、Ｎ　：０．００８％以下に制限し、さらに、Ｎｉ：０．１～１．５％、Ｃｒ：０．１～１．５％、Ｃｕ：０．１～１．０％、Ｍｏ：０．０５～０．５％の１種又は２以上を含有し、残部Ｆｅ及び不可避的不純物からなり、金属組織が、自己焼き戻しマルテンサイトの単独組織、又は、自己焼き戻しマルテンサイトと下部ベイナイトとの混合組織であることを特徴とする靭性と溶接性に優れた機械構造用高強度シームレス鋼管。
EP07740796A 2006-03-28 2007-03-27 High-strength seamless steel pipe for mechanical structure which has excellent toughness and weldability, and method for manufacture thereof Expired - Fee Related EP2028284B1 (en)

Applications Claiming Priority (2)

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JP2006087723A JP4751224B2 (ja) 2006-03-28 2006-03-28 靭性と溶接性に優れた機械構造用高強度シームレス鋼管およびその製造方法
PCT/JP2007/057360 WO2007114413A1 (ja) 2006-03-28 2007-03-27 靭性と溶接性に優れた機械構造用高強度シームレス鋼管及びその製造方法

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EP2028284A1 EP2028284A1 (en) 2009-02-25
EP2028284A4 EP2028284A4 (en) 2010-12-22
EP2028284B1 true EP2028284B1 (en) 2012-05-16

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US8821653B2 (en) 2011-02-07 2014-09-02 Dalmine S.P.A. Heavy wall steel pipes with excellent toughness at low temperature and sulfide stress corrosion cracking resistance
US9187811B2 (en) 2013-03-11 2015-11-17 Tenaris Connections Limited Low-carbon chromium steel having reduced vanadium and high corrosion resistance, and methods of manufacturing
US9188252B2 (en) 2011-02-18 2015-11-17 Siderca S.A.I.C. Ultra high strength steel having good toughness
US9340847B2 (en) 2012-04-10 2016-05-17 Tenaris Connections Limited Methods of manufacturing steel tubes for drilling rods with improved mechanical properties, and rods made by the same
US9598746B2 (en) 2011-02-07 2017-03-21 Dalmine S.P.A. High strength steel pipes with excellent toughness at low temperature and sulfide stress corrosion cracking resistance

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JP5020690B2 (ja) * 2007-04-18 2012-09-05 新日本製鐵株式会社 機械構造用高強度鋼管及びその製造方法
US7862667B2 (en) 2007-07-06 2011-01-04 Tenaris Connections Limited Steels for sour service environments
JP4959471B2 (ja) * 2007-08-28 2012-06-20 新日本製鐵株式会社 靭性に優れた機械構造用高強度シームレス鋼管及びその製造方法
MX2010005532A (es) 2007-11-19 2011-02-23 Tenaris Connections Ltd Acero bainítico de alta resistencia para aplicaciones octg.
JP2009235499A (ja) * 2008-03-27 2009-10-15 Nisshin Steel Co Ltd 中空スタビライザーの製造方法
US8221562B2 (en) 2008-11-25 2012-07-17 Maverick Tube, Llc Compact strip or thin slab processing of boron/titanium steels
EP2371982B1 (en) 2008-11-26 2018-10-31 Nippon Steel & Sumitomo Metal Corporation Seamless steel pipe and method for manufacturing same
BRPI1012964A2 (pt) 2009-06-11 2018-01-16 Nippon Steel Corp tubo de aço de alta resistência e método de produção do mesmo
US20100319814A1 (en) * 2009-06-17 2010-12-23 Teresa Estela Perez Bainitic steels with boron
JP5287553B2 (ja) * 2009-07-02 2013-09-11 新日鐵住金株式会社 降伏強度８８５ＭＰａ以上の非調質高張力厚鋼板とその製造方法
EP2325435B2 (en) 2009-11-24 2020-09-30 Tenaris Connections B.V. Threaded joint sealed to [ultra high] internal and external pressures
JP4860786B2 (ja) * 2010-03-05 2012-01-25 新日本製鐵株式会社 靭性に優れた機械構造用高強度シームレス鋼管とその製造方法
US20110253265A1 (en) * 2010-04-15 2011-10-20 Nisshin Steel Co., Ltd. Quenched and tempered steel pipe with high fatigue life, and its manufacturing method
US9163296B2 (en) 2011-01-25 2015-10-20 Tenaris Coiled Tubes, Llc Coiled tube with varying mechanical properties for superior performance and methods to produce the same by a continuous heat treatment
RU2457051C1 (ru) * 2011-03-23 2012-07-27 Государственное образовательное учреждение высшего профессионального образования "Южно-Уральский государственный университет" Способ прокатки и прессования полых профилей и устройство для его осуществления
WO2013007729A1 (en) 2011-07-10 2013-01-17 Tata Steel Ijmuiden Bv Hot-rolled high-strength steel strip with improved haz-softening resistance and method of producing said steel
CN102560283A (zh) * 2012-02-21 2012-07-11 张芝莲 一种大口径无缝合金钢管
WO2014086799A1 (en) * 2012-12-03 2014-06-12 Tata Steel Nederland Technology Bv A cold-rolled and continuously annealed high strength steel strip or sheet having a good deep-drawability and a method for producing said steel strip or sheet
AU2013372439B2 (en) 2013-01-11 2018-03-01 Tenaris Connections B.V. Galling resistant drill pipe tool joint and corresponding drill pipe
US9803256B2 (en) 2013-03-14 2017-10-31 Tenaris Coiled Tubes, Llc High performance material for coiled tubing applications and the method of producing the same
EP2789701A1 (en) 2013-04-08 2014-10-15 DALMINE S.p.A. High strength medium wall quenched and tempered seamless steel pipes and related method for manufacturing said steel pipes
EP2789700A1 (en) 2013-04-08 2014-10-15 DALMINE S.p.A. Heavy wall quenched and tempered seamless steel pipes and related method for manufacturing said steel pipes
KR102197204B1 (ko) 2013-06-25 2021-01-04 테나리스 커넥션즈 비.브이. 고크롬 내열철강
CN104561813B (zh) * 2014-12-30 2017-06-16 中车戚墅堰机车车辆工艺研究所有限公司 一种中碳硅锰系高耐磨空冷钢
CN105463311B (zh) * 2015-12-14 2017-11-07 徐州徐工液压件有限公司 一种高精度冷拔管的制作方法
CN107516569A (zh) * 2016-06-15 2017-12-26 董晓程 电磁铁用导套和隔磁套一体成型套管及其制备工艺
CN105908097A (zh) * 2016-06-30 2016-08-31 合肥慧林建材有限公司 一种耐热钢管及其生产工艺
CN106216430B (zh) * 2016-07-29 2018-09-04 新昌县长城空调部件股份有限公司 燃气厨具用输气管制造工艺
US11124852B2 (en) 2016-08-12 2021-09-21 Tenaris Coiled Tubes, Llc Method and system for manufacturing coiled tubing
US10434554B2 (en) 2017-01-17 2019-10-08 Forum Us, Inc. Method of manufacturing a coiled tubing string
CN114318128A (zh) * 2020-09-30 2022-04-12 宝山钢铁股份有限公司 一种自回火马氏体型高强韧性无缝钢管及其制造方法

Family Cites Families (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3250246B2 (ja) 1992-01-27 2002-01-28 日本鋼管株式会社 シリンダ用非調質高張力継目無鋼管
JPH0741856A (ja) 1993-07-28 1995-02-10 Nkk Corp 耐硫化物応力腐食割れ性に優れた高強度鋼管の製造法
JP3503211B2 (ja) 1994-09-30 2004-03-02 住友金属工業株式会社 高強度シームレス鋼管の製造方法
JP3965708B2 (ja) * 1996-04-19 2007-08-29 住友金属工業株式会社 靱性に優れた高強度継目無鋼管の製造方法
JPH10130783A (ja) 1996-10-28 1998-05-19 Kawasaki Steel Corp 非調質高強度継目無鋼管
JP3525666B2 (ja) 1997-01-24 2004-05-10 Ｊｆｅスチール株式会社 非調質高強度継目無鋼管
NO320153B1 (no) * 1997-02-25 2005-10-31 Sumitomo Metal Ind Stal med hoy seighet og hoy strekkfasthet, samt fremgangsmate for fremstilling
JPH10237583A (ja) * 1997-02-27 1998-09-08 Sumitomo Metal Ind Ltd 高張力鋼およびその製造方法
JPH10324946A (ja) 1997-05-27 1998-12-08 Komatsu Ltd 鋼管用高強度非調質鋼
JP3544455B2 (ja) 1997-07-19 2004-07-21 山陽特殊製鋼株式会社 継目無鋼管用高強度非調質鋼の製造方法
WO1999005334A1 (en) * 1997-07-28 1999-02-04 Exxonmobil Upstream Research Company Ultra-high strength, weldable, essentially boron-free steels wit h superior toughness
WO1999005336A1 (en) * 1997-07-28 1999-02-04 Exxonmobil Upstream Research Company Ultra-high strength, weldable, boron-containing steels with superior toughness
TW459052B (en) * 1997-12-19 2001-10-11 Exxon Production Research Co Ultra-high strength steels with excellent cryogenic temperature toughness
JP2001247931A (ja) 2000-03-07 2001-09-14 Nippon Steel Corp 非調質高強度継目無し鋼管およびその製造方法
JP3927056B2 (ja) * 2002-03-20 2007-06-06 Ｊｆｅスチール株式会社 高強度高靭性ベンド管の製造方法
JP3968011B2 (ja) * 2002-05-27 2007-08-29 新日本製鐵株式会社 低温靱性および溶接熱影響部靱性に優れた高強度鋼とその製造方法および高強度鋼管の製造方法
CN1208143C (zh) * 2002-11-25 2005-06-29 宝山钢铁股份有限公司 一种高性能无缝钢管的制造方法
JP3969328B2 (ja) 2003-03-26 2007-09-05 住友金属工業株式会社 非調質継目無鋼管
JP4475023B2 (ja) * 2004-06-10 2010-06-09 住友金属工業株式会社 低温靱性に優れた超高強度ベンド管

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8821653B2 (en) 2011-02-07 2014-09-02 Dalmine S.P.A. Heavy wall steel pipes with excellent toughness at low temperature and sulfide stress corrosion cracking resistance
US9598746B2 (en) 2011-02-07 2017-03-21 Dalmine S.P.A. High strength steel pipes with excellent toughness at low temperature and sulfide stress corrosion cracking resistance
US8636856B2 (en) 2011-02-18 2014-01-28 Siderca S.A.I.C. High strength steel having good toughness
US9188252B2 (en) 2011-02-18 2015-11-17 Siderca S.A.I.C. Ultra high strength steel having good toughness
US9222156B2 (en) 2011-02-18 2015-12-29 Siderca S.A.I.C. High strength steel having good toughness
US9340847B2 (en) 2012-04-10 2016-05-17 Tenaris Connections Limited Methods of manufacturing steel tubes for drilling rods with improved mechanical properties, and rods made by the same
US9187811B2 (en) 2013-03-11 2015-11-17 Tenaris Connections Limited Low-carbon chromium steel having reduced vanadium and high corrosion resistance, and methods of manufacturing

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