WO2012008486A1 - 二相組織油井鋼管及びその製造方法 - Google Patents
二相組織油井鋼管及びその製造方法 Download PDFInfo
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- WO2012008486A1 WO2012008486A1 PCT/JP2011/065968 JP2011065968W WO2012008486A1 WO 2012008486 A1 WO2012008486 A1 WO 2012008486A1 JP 2011065968 W JP2011065968 W JP 2011065968W WO 2012008486 A1 WO2012008486 A1 WO 2012008486A1
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L9/00—Rigid pipes
- F16L9/02—Rigid pipes of metal
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- 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
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0226—Hot rolling
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- 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
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- 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
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
- C21D8/0263—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment following hot rolling
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- 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
- C21D8/105—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of tubular bodies of ferrous alloys
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- 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
- C21D9/14—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for tubular bodies or pipes wear-resistant or pressure-resistant pipes
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- 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
- C22C38/001—Ferrous alloys, e.g. steel alloys containing N
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- 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
- C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
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- 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
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
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- 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
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- 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
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
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- 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
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- 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
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- 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
- C21D2211/005—Ferrite
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- 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
- a hot-rolled steel sheet having an optimized composition is formed into a steel pipe, the steel pipe is heated to a temperature at which two phases of austenite and ferrite coexist (two-phase region), and then subjected to a quenching treatment.
- the present invention relates to a two-phase oil well steel pipe excellent in pipe expandability with controlled structure and a manufacturing method thereof.
- the Bauschinger effect is a phenomenon in which when a plastic strain is applied by plastic deformation and then a stress is applied in a direction opposite to the direction in which the plastic strain is applied, the yield stress in that direction is reduced compared to that before the plastic deformation.
- Patent Documents 1 and 2 propose steel pipes having excellent crush characteristics after pipe expansion.
- the steel pipe disclosed in Patent Document 1 has a microstructure of bainite or bainitic ferrite, and after expanding the pipe, solid solution C is fixed to dislocations to increase the crushing strength.
- the steel pipe disclosed in Patent Document 2 has a two-phase structure composed of ferrite and finely dispersed martensite in which the expression of the Bauschinger effect is suppressed.
- Patent Document 3 is effective to increase the work hardening index (n value).
- n value the work hardening index
- the metal structure of the steel pipe disclosed in Patent Document 3 is that the soft phase is ferrite, tempered martensite, and tempered bainite, and the hard phase is a hybrid of martensite and austenite (Martensite-Austenite Constituent: MA).
- the steel pipe is heated to a two-phase region, air-cooled, and the hard phase is MA.
- the oil-phase steel tube with a two-phase structure has a high n value.
- the yield strength Yield Stress: YS
- YS is an important factor related to crushing strength, and when YS decreases, the crushing strength also tends to decrease.
- the present invention provides a two-phase well oil pipe manufactured by a two-phase quenching process and excellent in both YS and n-value characteristics.
- each aspect of the present invention has the following configuration.
- the two-phase structure oil well steel pipe according to one embodiment of the present invention is: C: 0.07% to 0.15%, Si: 0.1% to 0.5%, Mn: 0.8% to 1.9%, Nb: 0.020% to 0.10%, Containing P: 0.05% or less, S: 0.01% or less, Al: 0.1% or less,
- the balance is composed of Fe and inevitable impurities, the carbon equivalent Ceq obtained by (Equation 1) is 0.25 to 0.40, and the content of the element X in which [X] is expressed by mass% [Nb] ⁇ [C] ⁇ 0.002 is satisfied, and the metal structure composition of the dual-phase steel pipe is 80% to 98% ferrite in terms of area ratio, and 2% to 20% in total.
- Martensite, retained austenite, or a mixed phase thereof wherein the ferrite has an average particle size of 1 ⁇ m or more and less than 8 ⁇ m, and the martensite, the retained austenite, or the mixed phase has an average particle size of 0.1 ⁇ m. 1 ⁇ m or more and 2 ⁇ m or less.
- Ceq [C] + [Mn] / 6 (Formula 1)
- [X] represents the content of the element X expressed in mass%.
- the two-phase structure oil well steel pipe of the above (1) has a chemical composition of mass%, V: 0.0001% to 0.02%, Ti: 0.005% to 0.03%, Ca: 0.001% to 0.010%, N: 0.001% to 0.01%, 1 or 2 or more, and when [X] is the content [% by mass] of the element X, [V] / [Nb] ⁇ 1/3 is satisfied, and the carbon equivalent Ceq May be defined as (Expression 2) instead of (Expression 1).
- Ceq [C] + [Mn] / 6 + [V] / 5 (Formula 2)
- [X] represents the content of the element X expressed in mass%.
- the Nb content is 0.040% to 0.10%, and the content of element X in which [X] is expressed in mass% Then, [Nb] ⁇ [C] ⁇ 0.003 may be satisfied.
- the two-phase well oil pipe of the above (1) or (2) may have a plate thickness of 5 mm to 15 mm.
- the chemical composition is mass%, C: 0.07% to 0.15%, Si: 0.1% to 0.5%, Mn: 0.8% to 1.9%, Nb: 0.020% to 0.10%, Containing P: 0.05% or less, S: 0.01% or less, Al: 0.1% or less,
- the balance is composed of Fe and inevitable impurities, the carbon equivalent Ceq obtained by (Equation 3) is 0.25 to 0.40, and the content of the element X in which [X] is expressed in mass%
- the steel material that satisfies [Nb] ⁇ [C] ⁇ 0.002 is hot-rolled under the condition that the average grain size of ferrite is 1 ⁇ m or more and less than 10 ⁇ m, and a hot-rolled steel sheet is obtained.
- Have. Ceq [C] + [Mn] / 6 (Formula 3)
- [X] represents the content of the element X expressed in mass%.
- the chemical composition of the steel material is% by mass, V: 0.0001% to 0.02%, Ti: 0.005% to 0.03%, Ca: 0.001% to 0.010%, N: 0.001% to 0.01%, 1 or 2 or more, and when [X] is the content [% by mass] of the element X, [V] / [Nb] ⁇ 1/3 is satisfied, and the carbon equivalent Ceq May be defined as (Expression 4) instead of (Expression 3).
- Ceq [C] + [Mn] / 6 + [V] / 5 (Formula 4)
- [X] represents the content of the element X expressed in mass%.
- n value and YS which are the basic physical properties of the two-phase well oil pipe according to the present embodiment.
- Steel pipes A, D, and G were formed from hot-rolled steel sheets having different component compositions and metal structures. These steel pipes were heated to a two-phase region temperature where the metal structure becomes austenite and ferrite, and subjected to a two-phase region quenching treatment to obtain a two-phase structure oil well steel tube.
- the YS and n values of these two-phase structure oil well steel pipes were changed by variously changing the heat treatment conditions within the two-phase region temperature range.
- FIG. 1 the relationship between YS and n value of the steel pipes A, D, and G is shown. From this figure, it is shown that in any steel pipe, the n value decreases as YS increases. Further, it is shown that the absolute value of the inclination is 5.5 to 5.6 ⁇ 10 ⁇ 4 MPa ⁇ 1 in any steel pipe.
- An object of the present invention is to improve both the YS and n-value characteristics of a duplex steel pipe.
- FIG. 1 shows that both the YS and n-value characteristics are enhanced in the steel pipe D rather than the steel pipe G, and further in the steel pipe A than the steel pipe D. Therefore, in the two-phase well oil pipe according to the present embodiment, the fact that the linear relationship between YS and the n value exists in the hatched area in FIG. In this case, the n value when YS is 380 MPa is 0.2 or more. That is, the two-phase well oil pipe according to the present embodiment aims to satisfy the following (formula A).
- n which is a work hardening index.
- the n value is obtained from the slope when the true stress-true strain curve is displayed in logarithmic form.
- requires n value shall be a range from 2% to a uniform elongation by nominal distortion.
- the two-phase oil well steel pipe according to this embodiment is manufactured by the following steps. (1) A step of producing a hot-rolled steel sheet by hot rolling using a steel material having a component composition to be described later under the condition that the average grain size of ferrite is 1 ⁇ m or more and less than 10 ⁇ m. (2) A step of forming a steel pipe from the hot-rolled steel sheet. (3) A step of heating the steel pipe to an austenite transformation start temperature Ac 1 higher than an austenite transformation end temperature Ac 3 and quenching (two-phase region quenching).
- the two-phase structure oil well steel pipe which concerns on this embodiment can be obtained by manufacturing with the said process using the steel material of the below-mentioned component composition.
- the average grain size of ferrite in the metal structure of the hot-rolled steel sheet be 1 ⁇ m or more and less than 10 ⁇ m. This is for controlling the ferrite average particle size of the two-phase microstructure oil well steel pipe after the two-phase quenching process to be 1 ⁇ m or more and less than 8 ⁇ m. Making the average particle diameter of ferrite of the hot-rolled steel sheet less than 1 ⁇ m is substantially difficult to achieve in production.
- the hot rolled steel sheet has an average ferrite particle size of 1 ⁇ m or more and less than 8 ⁇ m.
- the average particle size of the ferrite phase is determined by a cutting method in accordance with JIS G 0552.
- the metal structure of the hot-rolled steel sheet includes pearlite, bainite, carbides and nitrides as precipitates in addition to ferrite as the main phase.
- this steel sheet is subjected to a two-phase quenching treatment after pipe making, only the average grain size of ferrite is an important control factor in this process.
- the ferrite average grain size 1 ⁇ m or more and less than 10 ⁇ m, in addition to the precipitation of Nb carbide described later, it is possible to control the cumulative reduction ratio in the finish rolling of the hot rolling and the final pass temperature of the hot rolling. is important.
- the hot rolled steel sheet for oil well steel pipes preferably has a finished sheet thickness of 5 mm to 15 mm.
- the rolling reduction is as large as possible and the final rolling pass temperature is 900 ° C. or lower.
- the hot rolling method is not particularly limited as long as the ferrite average particle size of the metallographic structure of the hot rolled steel sheet having a thickness of 5 mm to 15 mm is 1 ⁇ m or more and less than 10 ⁇ m.
- the heating temperature of the steel material is preferably 1000 ° C. to 1300 ° C., and more preferably 1150 ° C. to 1250 ° C.
- the final pass temperature of hot rolling is preferably a temperature at which recrystallization hardly occurs (non-recrystallization temperature region), and is preferably in the range of 750 ° C. to 900 ° C.
- the hot-rolled steel plate is water-cooled and wound up.
- the winding temperature is preferably 500 ° C to 700 ° C.
- a hot-rolled steel sheet is accelerated-cooled, and it cools after that.
- ERW steel pipe In the step of forming a steel pipe from the steel plate, pipe making is performed on an electric resistance steel pipe, a UOE steel pipe, or the like, and an electric resistance steel pipe is preferable.
- the reason why the ERW steel pipe is preferable is that it has excellent productivity, relatively uniform wall thickness, and excellent pipe expandability and crushing strength.
- An electric resistance steel pipe is manufactured by roll-forming a hot-rolled steel sheet into a tubular shape and welding the seam portion by electric resistance welding.
- the UOE steel pipe is manufactured by subjecting a thick steel plate after hot rolling to C-pressing, U-pressing, and O-pressing in a UOE process, and submerged arc welding of the seam portion.
- the steel pipe is heated to a two-phase region, that is, a temperature range of more than Ac 1 point and less than Ac 3 point, and then quenching is performed.
- a two-phase region that is, a temperature range of more than Ac 1 point and less than Ac 3 point
- the above Ac 1 and Ac 3 values are obtained by measuring specimens taken from a steel pipe before the two-phase quenching process, or by manufacturing and measuring a steel material having a similar composition in the laboratory.
- the transformation temperature during heating of steel can be determined by a so-called Formaster test in which a test piece is heated at a constant speed and the amount of expansion is measured.
- the quenching method may be selected from water quenching, oil quenching, liquid nitrogen quenching, and the like according to the steel pipe.
- the metal structure of the two-phase oil well steel pipe according to this embodiment is a two-phase structure of a ferrite phase and a hard second phase.
- so-called bainitic ferrite in which carbides and hard second phases are found inside the grains is not included in the ferrite phase here.
- the hard second phase is martensite, retained austenite, or a mixed phase thereof, and generally refers to one that is confirmed by a repeller etch.
- This metallographic structure is observed with an optical microscope by collecting a test piece from the outer surface of the steel pipe at a quarter of the wall thickness, polishing and etching.
- the metal structure includes a slight amount of deposits such as pearlite, bainite, carbide, and nitride. However, since the area ratio is lower than that of the ferrite phase and the hard second phase, the above metal structure composition is not considered.
- Ferrite area ratio 80% to 98% Ferrite is the main phase in the metal structure.
- the area ratio of ferrite is 80% to 98%. If it is less than 80%, the relative ratio of the hard second phase, pearlite or bainite increases, and the above (formula A) cannot be satisfied. Even if it exceeds 98%, the above (formula A) cannot be satisfied.
- Average particle diameter of ferrite 1 ⁇ m or more and less than 8 ⁇ m
- the average particle diameter of ferrite is 1 ⁇ m or more and less than 8 ⁇ m.
- a thickness of less than 1 ⁇ m is substantially difficult to achieve in manufacturing. If it is 8 ⁇ m or more, it is too coarse to contribute to the improvement of YS and n value, and toughness also decreases.
- the average particle diameter of the ferrite is 1 ⁇ m or more and less than 5 ⁇ m.
- the average particle diameter of a ferrite phase is calculated
- Martensite, retained austenite, or area ratio of these mixed phases 2% to 20% in total Martensite, retained austenite, or a mixed phase of these is a hard second phase that is finely dispersed in the metal structure to constrain the deformation of the ferrite phase during plastic deformation and improve YS and n value.
- the area ratio of martensite, retained austenite, or a mixed phase thereof is 2% to 20% in total. If the total is less than 2%, it does not contribute to the improvement of YS and n value. If it exceeds 20% in total, it will be hardened too much, making the balance between strength and ductility unsuitable for oil well steel pipes.
- the area ratio of martensite, retained austenite, which is a hard second phase, or a mixed phase thereof is obtained by image processing.
- the hard second phase can be discriminated from ferrite by repeller etching.
- image processing the average area of the hard second phase is obtained and converted into an area ratio.
- Average particle size of martensite, residual austenite, or mixed phase thereof 0.1 ⁇ m or more and 2 ⁇ m or less
- the average particle size of martensite, residual austenite, or mixed phase thereof is 0.1 ⁇ m or more and 2 ⁇ m or less.
- a thickness of less than 0.1 ⁇ m is substantially difficult to achieve in manufacturing. If it exceeds 2 ⁇ m, it is too coarse to contribute to the improvement of YS and n value, and also serves as a starting point for destruction. In order to exhibit the effect optimally, it is preferable that the average particle size of martensite or retained austenite is 0.1 ⁇ m or more and 1 ⁇ m or less.
- the average particle size of martensite, retained austenite, or a mixed phase thereof, which is a hard second phase, is determined by image processing.
- the hard second phase can be discriminated from ferrite by repeller etching.
- image processing the average area and number of hard second phases are determined, and the average particle diameter is calculated as the equivalent circle diameter.
- a steel material to which fine Nb carbides are precipitated by adding Nb and C is used.
- this Nb carbide exhibits a pinning effect and suppresses austenite grain growth during hot rolling. And also at the time of cooling after hot rolling, this Nb carbide exhibits a pinning effect and suppresses the grain growth of ferrite generated from the austenite grain boundary. For this reason, the metal structure of the hot-rolled steel sheet is a fine structure.
- austenite is generated from ferrite grain boundaries.
- austenite generated during heating to the two-phase region is also finely dispersed in the metal structure. It becomes possible. As a result, the hard second phase martensite, retained austenite, or a mixed phase thereof is finely dispersed in the metal structure after the two-phase quenching process, so the YS and n values of the two-phase oil well steel pipe increase. . Further, the Nb carbide is finely dispersed in the ferrite grains and suppresses the dislocation activity during plastic deformation, and thus has an effect of improving the YS and n value of the dual-phase oil well steel pipe.
- C 0.07% to 0.15%
- C is an element that improves the strength of the steel and contributes to the improvement of the n value of the dual-phase steel pipe.
- the C content is 0.07% to 0.15%. If it is less than 0.07%, it is difficult to make the n value 0.20 or more when YS is 380 MPa. If it exceeds 0.15%, the formation of carbides is promoted, YS increases, and the n value decreases.
- Si 0.1% to 0.5%
- Si is a deoxidizing element.
- the amount of Si is 0.1% to 0.5%. If it is less than 0.1%, the deoxidation effect cannot be obtained. If it exceeds 0.5%, non-uniform scale is generated, which adversely affects the surface shape.
- the Si content is preferably 0.2% to 0.4% in order to achieve the optimum effect from the viewpoint of the abutting portion toughness.
- Mn 0.8% to 1.9%
- Mn is an element that contributes to hardenability and improves strength.
- the amount of Mn is 0.8% to 1.9%. If it is less than 0.8%, the strength is insufficient. If it exceeds 1.9%, segregation is promoted and martensite is formed in a layered manner, and the n value decreases.
- the amount of Mn is preferably 1.0% to 1.5%.
- Nb 0.020% to 0.10%
- Nb is an element that expands the non-recrystallization temperature range and refines the crystal grain size to form carbides and nitrides and contributes to improvement in strength.
- Nb is an element that contributes to the improvement of the n value.
- the Nb content is 0.020% to 0.10%. If it is less than 0.020%, it is difficult to make the n value 0.20 or more when YS is 380 MPa. If it exceeds 0.10%, YS increases and the n value decreases. In order to achieve the optimum effect, the Nb content is preferably 0.040% to 0.10%.
- [Nb] ⁇ [C] ⁇ 0.002 By increasing the addition amount of Nb and C, the hard second phase is finely dispersed in the metal structure, and it becomes possible to simultaneously increase the YS and n value of the two-phase structure steel pipe.
- content of the element X which represented [X] in the mass% [Nb] x [C] shall be 0.002 or more. If it is less than 0.002%, it is difficult to make the n value 0.20 or more when YS is 380 MPa. In order to achieve the optimum effect, it is preferable to set [Nb] ⁇ [C] to 0.003 or more.
- the lower limit of the amount of impurities below may be 0%.
- the unit of content is mass%.
- P 0.05% or less
- P is an impurity, and if it is excessively contained, tube expandability is impaired.
- the amount of P is limited to 0.05% or less.
- the upper limit with preferable P amount is 0.02% or less.
- S 0.01% or less S is an impurity, and if contained excessively, hot workability and tube expandability are impaired.
- the amount of S is limited to 0.01% or less.
- the upper limit with the preferable amount of S is 0.005% or less.
- Al 0.1% or less Al is a deoxidizing element. However, when the amount added is increased, inclusions increase, ductility decreases, and pipe expandability is impaired. The amount of Al is limited to 0.1% or less. A preferable upper limit of the Al amount is 0.03% or less. When Si or Ti is used as a deoxidizer, it is not necessary to add Al, but in order to reduce the amount of oxygen in the molten steel, it is preferable to add 0.0005% or more of Al.
- the selected elements are described below.
- the addition of the selective element is not essential, and the amount of the selective element may be 0%.
- the unit of content is mass%.
- V 0.0001% to 0.02%
- V is a selective element that forms carbides and nitrides, and may be added to improve strength or refine the structure. However, when V is added, the n value decreases. Therefore, the V amount is preferably 0.0001% to 0.02%. If it is less than 0.0001%, it is below the detection limit in component analysis, and control at that level is difficult. If it exceeds 0.02%, the n value decreases. In order to prevent a decrease in the n value, the V amount is more preferably 0.0001% to 0.01%.
- [V] / [Nb] ⁇ 1/3 When it is necessary to add V for strength improvement, it is preferable to relatively increase the Nb amount. Thereby, the fall of n value can be suppressed. In order to suppress a decrease in the n value, it is preferable to set [V] / [Nb] to 1/3 or less. In order to achieve the optimum effect, it is more preferable to set [V] / [Nb] to 1/4 or less. V is an element that is selectively contained, and [V] is 0 when not intentionally added. Therefore, the lower limit value of [V] / [Nb] is not particularly defined, but may be 0.
- Carbon equivalent Ceq 0.25 to 0.40
- the carbon equivalent Ceq in the above (Formula 2) is preferably 0.25 to 0.40. If it is less than 0.25, it is difficult to secure a hard second phase and increase the n value. If it exceeds 0.40%, the strength becomes too high and the n value decreases.
- Ti is a selective element that forms carbides and nitrides, improves strength and refines the structure.
- the amount of Ti is preferably 0.005% to 0.030%. If it is less than 0.005%, there is no effect of improving the strength or miniaturizing the structure. If it exceeds 0.030%, coarse carbides and nitrides are formed, which does not contribute to improvement of strength and refinement of the structure, and lowers the n value. In order to exhibit the effect optimally, the Ti amount equal to or higher than the atomic ratio is more preferable according to the N amount.
- Ca 0.001% to 0.010%
- Ca is a selective element that prevents the oxide from coarsening and improves the tube expansion characteristics.
- the Ca content is preferably 0.001% to 0.010%. If it is less than 0.001%, there is no effect of preventing the oxide from coarsening. If it exceeds 0.010%, coarse Ca oxide may be generated, and the tube expansion characteristics may deteriorate. In order to achieve the optimum effect, the Ca content is more preferably 0.001% to 0.004%.
- N 0.001% to 0.01%
- N is a selective element that forms nitrides with Nb, Ti, V, etc., suppresses coarsening of austenite grains during slab reheating, refines the base material structure, and improves YS and n value Contribute.
- the amount of N is preferably 0.001% to 0.01%. If it is less than 0.001%, there is no effect of improving the YS and the n value. If it exceeds 0.004%, the nitride becomes coarse, and the effects of precipitation strengthening and refinement of the structure cannot be obtained.
- the present invention will be further described based on examples, but the conditions in the examples are one condition example adopted to confirm the feasibility and effects of the present invention, and the present invention is limited to this one condition example. Not.
- the present invention can adopt various conditions as long as the object of the present invention is achieved without departing from the gist of the present invention.
- a hot rolled steel sheet having a chemical thickness shown in Table 1 and having a thickness of 9.5 mm was used to manufacture an electric resistance steel pipe having a diameter of 197 mm.
- the hot-rolled steel sheet was obtained from hot rolling under processing conditions in which the heating temperature was 1200 ° C., the final pass temperature of hot rolling was 800 ° C., and the winding temperature after water cooling on the run-out table was 550 ° C.
- the ERW steel pipe made from this hot-rolled steel sheet was heated to the temperature shown in Table 2, water-quenched, and controlled to a two-phase structure.
- the hot-rolled steel sheet a sample was taken with the cross section parallel to the rolling direction as the observation surface, polished and etched, and the metal structure was observed with an optical microscope.
- a sample of a duplex-structure steel pipe was taken with the cross section in the circumferential direction of the 1/4 part of the wall thickness from the outer surface as the observation surface, and after the repeller etching, the structure was observed with an optical microscope.
- the average particle diameter of the ferrite phase was determined by the cutting method of JIS G 0552, and the average particle diameter of martensite, retained austenite, which is a hard second phase, or a mixed phase thereof was determined by image processing. Asked.
- a round bar tensile test material in which the axial direction of the steel pipe is the longitudinal direction and the diameter of the parallel part is 6 mm ⁇ was collected, and a tensile test was performed in accordance with JIS Z 2241 to obtain YS.
- the n value was calculated from the slope of the true stress-true strain curve in the range from 2% to uniform elongation.
- Table 2 shows the following formula (right side of (Formula A)) from the measured YS. ⁇ 5.55 ⁇ 10 ⁇ 4 [YS] +0.411
- the determination criterion n value obtained using is also shown.
- the measured n value is larger than the determination criterion n value, it can be determined that both the YS and n values are increased.
- Production No. which is a dual-phase steel pipe of Example. In 1 to 6, the measured n value is higher than the determination reference n value, and both high n value and high YS are compatible.
- production No. which is a comparative example. 7 to 13 the measured n value is lower than the determination reference n value.
- No. No. 7 is an example in which the value of [Nb] ⁇ [C] is small, so that the average ferrite grain size of the duplex-structured steel pipe and the average grain size of the hard second phase are increased, and the n value is lowered.
- No. 8 is an example in which the value of n is lowered because the value of [V] / [Nb] is high.
- No. 9 is an example in which the n value is lowered because the Nb content is low.
- No. No. 10 is an example in which the n value is decreased because the V content is large and the ferrite average particle diameter of the dual phase structure steel pipe is large.
- No. 11 is an example in which the n value was lowered because the contents of C and Mn were large and the value of Ceq was high.
- No. No. 12 is an example in which the area ratio of the hard second phase is large, so that YS increases and the n value is not satisfied.
- No. No. 13 is an example in which the hard second phase was not generated because the quenching was performed from a temperature range where the heating temperature for quenching was high and the structure became austenite, and the n value was lowered.
- a hot-rolled steel sheet with an optimized component composition is formed into a steel pipe, the steel pipe is heated to a temperature (two-phase region) in which two phases of austenite and ferrite coexist, and then quenched. Therefore, it is possible to obtain a two-phase oil well steel pipe excellent in pipe expandability by simultaneously improving both YS and n value characteristics, which is industrially useful.
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Abstract
Description
本願は、2010年7月13日に、日本に出願された特願2010-159013号に基づき優先権を主張し、その内容をここに援用する。
(1) 本発明の一態様にかかる二相組織油井鋼管は:その化学組成が、質量%で、
C :0.07%~0.15%、
Si:0.1%~0.5%、
Mn:0.8%~1.9%、
Nb:0.020%~0.10%、
を含有し、
P :0.05%以下、
S :0.01%以下、
Al:0.1%以下、
に制限し、残部がFe及び不可避的不純物からなり、(式1)によって求められる炭素等量Ceqが0.25~0.40であり、[X]を、質量%で表した元素Xの含有量としたとき、[Nb]×[C]≧0.002が満足され、前記二相組織鋼管の金属組織組成が、面積率で、80%~98%のフェライトと、合計2%~20%のマルテンサイト、残留オーステナイト、またはこれらの混合相と、を含み、前記フェライトの平均粒径が1μm以上8μm未満であり、前記マルテンサイト、前記残留オーステナイト、または前記混合相の平均粒径が0.1μm以上2μm以下である。
Ceq=[C]+[Mn]/6 ・・・ (式1)
ここで、[X]は、質量%で表した元素Xの含有量を表す。
V :0.0001%~0.02%、
Ti:0.005%~0.03%、
Ca:0.001%~0.010%、
N :0.001%~0.01%、
の1種又は2種以上を更に含有し、[X]を、元素Xの含有量[質量%]としたとき、[V]/[Nb]≦1/3が満足され、前記炭素等量Ceqが前記(式1)に代わって、(式2)と定義されてもよい。
Ceq=[C]+[Mn]/6+[V]/5 ・・・ (式2)
ここで、[X]は、質量%で表した元素Xの含有量を表す。
C :0.07%~0.15%、
Si:0.1%~0.5%、
Mn:0.8%~1.9%、
Nb:0.020%~0.10%、
を含有し、
P :0.05%以下、
S :0.01%以下、
Al:0.1%以下、
に制限し、残部がFe及び不可避的不純物からなり、(式3)によって求められる炭素等量Ceqが0.25~0.40であり、[X]を、質量%で表した元素Xの含有量としたとき、[Nb]×[C]≧0.002が満足される鋼材を用いて、フェライトの平均粒径が1μm以上10μm未満となる条件で熱間圧延して、熱間圧延鋼板を製造する工程と、前記熱間圧延鋼板から鋼管を造管する工程と、前記鋼管を、オーステナイト変態の開始温度Ac1超、オーステナイト変態終了温度Ac3未満に加熱し、焼入れ処理する工程と、を有する。
Ceq=[C]+[Mn]/6 ・・・ (式3)
ここで、[X]は、質量%で表した元素Xの含有量を表す。
V :0.0001%~0.02%、
Ti:0.005%~0.03%、
Ca:0.001%~0.010%、
N :0.001%~0.01%、
の1種又は2種以上を更に含有し、[X]を、元素Xの含有量[質量%]としたとき、[V]/[Nb]≦1/3が満足され、前記炭素等量Ceqが前記(式3)に代わって、(式4)と定義されてもよい。
Ceq=[C]+[Mn]/6+[V]/5 ・・・ (式4)
ここで、[X]は、質量%で表した元素Xの含有量を表す。
YSが380MPaである場合に、n値が0.2以上であることを表す下式、
[n]≧0.20-5.55×10-4([YS]-380)
を変形して、下記(式A)が得られる。
[n]≧-5.55×10-4[YS]+0.411 ・・・ (式A)
Ceq=[C]+[Mn]/6 ・・・ (式1)
と定義したとき、(式1)によって求められる炭素等量Ceqが0.25~0.40であり、[Nb]×[C]≧0.002が満足される成分組成。
フェライトは金属組織中での主相である。フェライトの面積率を80%~98%とする。80%未満では、硬質第二相、またはパーライトやベイナイトの相対的な割合が増え、上記(式A)を満足できなくなる。98%超でも、上記(式A)を満足できなくなる。
フェライトの平均粒径は、1μm以上8μm未満とする。1μm未満へは、実質的に製造上で達成が困難である。8μm以上では、粗大すぎてYSとn値との向上に寄与せず、靱性も低下する。最適に効果を発現させるには、フェライトの平均粒径が、1μm以上5μm未満であることが好ましい。なお、フェライト相の平均粒径は、JIS G 0552に則って切断法により求める。
マルテンサイト、残留オーステナイト、またはこれらの混合相は、硬質第二相であり、金属組織内で微細に分散することによって、塑性変形時にフェライト相の変形を拘束して、YSとn値とを向上させる。マルテンサイト、残留オーステナイト、またはこれらの混合相の面積率は、合計2%~20%とする。合計2%未満だと、YSとn値との向上に寄与しない。合計20%超だと、硬化しすぎるため、油井鋼管として強度―延性のバランスが不適となる。なお、硬質第二相であるマルテンサイト、残留オーステナイト、またはこれらの混合相の面積率は、画像処理によって求める。硬質第二相は、レペラーエッチによって、フェライトとの判別が可能になる。画像処理によって、硬質第二相の平均面積を求め、面積率に換算する。
マルテンサイト、残留オーステナイト、またはこれらの混合相の平均粒径は、0.1μm以上2μm以下とする。0.1μm未満へは、実質的に製造上で達成が困難である。2μm超では、粗大すぎてYSとn値との向上に寄与せず、また、破壊の起点にもなる。最適に効果を発現させるには、マルテンサイト又は残留オーステナイトの平均粒径が、0.1μm以上1μm以下であることが好ましい。なお、硬質第二相であるマルテンサイト、残留オーステナイト、またはこれらの混合相の平均粒径は、画像処理によって求める。硬質第二相は、レペラーエッチによって、フェライトとの判別が可能になる。画像処理によって、硬質第二相の平均面積と個数とを求め、平均粒径を円相当径として算出する。
Cは、鋼の強度を向上させる元素であり、二相組織鋼管のn値の向上にも寄与する。C量は、0.07%~0.15%とする。0.07%未満では、YSを380MPaとした際のn値を0.20以上にすることが困難である。0.15%超では、炭化物の生成が促進されてYSが高くなり、n値が低下する。
Siは、脱酸元素である。Si量は、0.1%~0.5%とする。0.1%未満では、脱酸効果が得られない。0.5%超では、不均一なスケールが発生し、表面形状に悪影響を及ぼす。電縫鋼管などは衝合部靱性の観点から最適に効果を発現させるには、Si量が、0.2%~0.4%であることが好ましい。
Mnは、焼入れ性に寄与し、強度を向上させる元素である。Mn量は、0.8%~1.9%とする。0.8%未満では、強度が不足となる。1.9%超では、偏析を助長してマルテンサイトが層状に形成され、n値が低下する。最適に効果を発現させるには、Mn量が、1.0%~1.5%であることが好ましい。
Nbは、未再結晶温度域を拡大して結晶粒径を微細化し、炭化物、窒化物を形成し、強度の向上に寄与する元素である。また、Nbは、n値の向上に寄与する元素である。Nb量は、0.020%~0.10%とする。0.020%未満では、YSを380MPaとした際のn値を0.20以上にすることが困難である。0.10%超では、YSが高くなり、n値が低下する。最適に効果を発現させるには、Nb量が、0.040%~0.10%であることが好ましい。
Nb及びCの添加量を増加させることによって、硬質第二相が金属組織中で微細に分散し、二相組織鋼管のYSとn値とを同時に高めることが可能になる。[X]を質量%で表した元素Xの含有量として、[Nb]×[C]は、0.002以上とする。0.002%未満では、YSを380MPaとした際のn値を0.20以上にすることが困難である。最適に効果を発現させるには、[Nb]×[C]を0.003以上にすることが好ましい。
Ceqは焼入れ性の指標である。一般に、Ceqは、[X]を質量%で表した元素Xの含有量として、下式で定義される。
Ceq=[C]+[Mn]/6+([Ni]+[Cu])/15+([Cr]+[Mo]+[V])/5
しかし、上記二相組織油井鋼管の基本成分には、Ni、Cu、Cr、Mo、Vが含有されないので、CとMnとの含有量から、Ceqを下式(式1)に定義する。
Ceq=[C]+[Mn]/6 ・・・ (式1)
上記(式1)での炭素等量Ceqが、0.25~0.40である必要がある。0.25未満では、硬質第二相を確保し、n値を高めることが困難である。0.40%超では、強度が高くなりすぎて、n値が低下する。
Pは不純物であり、過剰に含有すると拡管性を損なう。P量は、0.05%以下に制限する。P量の好ましい上限は、0.02%以下である。
Sは不純物であり、過剰に含有すると熱間加工性や拡管性を損なう。S量は、0.01%以下に制限する。S量の好ましい上限は、0.005%以下である。
Alは、脱酸元素であるが、添加量が多くなると、介在物が増加して延性が低下し、拡管性を損なう。Al量は、0.1%以下に制限する。Al量の好ましい上限は、0.03%以下である。脱酸剤としてSiやTiを使用する場合にはAlを添加する必要はないが、溶鋼中の酸素量を低減させるために、Alを0.0005%以上添加することが好ましい。
Vは、炭化物、窒化物を形成する選択元素であり、強度の向上や組織の微細化のために添加してもよい。しかし、Vを添加するとn値が低下する。よって、V量は、0.0001%~0.02%とすることが好ましい。0.0001%未満は、成分分析での検出限界以下であり、そのレベルでの制御は困難である。0.02%超では、n値が低下する。n値の低下を防止するためには、V量が、0.0001%~0.01%であることが更に好ましい。
強度向上のためにVを添加する必要がある場合には、相対的にNb量を高めることが好ましい。これにより、n値の低下を抑制することができる。n値の低下を抑制するためには、[V]/[Nb]を1/3以下とすることが好ましい。最適に効果を発現させるには、[V]/[Nb]を1/4以下とすることが更に好ましい。Vは選択的に含有される元素であり、意図的に添加しない場合は、[V]が0となる。したがって、 [V]/[Nb]の下限値は特に規定しないが、0でもよい。
選択元素であるVが含有される場合には、上記炭素当量Ceqの上記(式1)に代わって、
Ceq=[C]+[Mn]/6+[V]/5 ・・・ (式2)
と定義する。選択元素であるVが含有される場合には、上記(式2)での炭素等量Ceqが、0.25~0.40であることが好ましい。0.25未満では、硬質第二相を確保し、n値を高めることが困難である。0.40%超では、強度が高くなりすぎて、n値が低下する。
Tiは、炭化物、窒化物を形成し、強度の向上や組織を微細化する選択元素である。Ti量は、0.005%~0.030%とすることが好ましい。0.005%未満では、強度の向上や、組織の微細化の効果がない。0.030%超では、粗大な炭化物や窒化物が形成され、強度の向上や組織の微細化に寄与しなくなり、n値を低下させる。最適に効果を発現させるには、N量に応じて原子比以上のTi量が更に好ましい。
Caは、酸化物の粗大化を防止し、拡管特性を向上する選択元素である。Ca量は、0.001%~0.010%とすることが好ましい。0.001%未満では、酸化物の粗大化を防止する効果がない。0.010%超では、粗大なCa酸化物が生成し拡管特性が低下することがある。最適に効果を発現させるには、Ca量が、0.001%~0.004%であることが更に好ましい。
Nは、Nb、Ti、V等と窒化物を形成する選択元素であり、スラブ再加熱時のオーステナイト粒の粗粒化を抑制して母材の組織を微細化し、YS及びn値の向上に寄与する。N量は、0.001%~0.01%とすることが好ましい。0.001%未満では、YSとn値とを向上させる効果がない。0.004%超では、窒化物が粗大になり、析出強化や組織の微細化の効果が得られなくなる。
-5.55×10-4[YS]+0.411
を用いて求めた判定基準n値も示した。実測のn値が、この判定基準n値よりも大きい場合、YSとn値との両方の値が高まっていると判断できる。実施例の二相組織鋼管である製造No.1~6は、実測のn値が判定基準n値よりも高く、高n値及び高YSが両立されている。一方、比較例である製造No.7~13は、実測のn値が判定基準n値よりも低くなっている。
Claims (6)
- 二相組織鋼管であって、その化学組成が、質量%で、
C :0.07%~0.15%、
Si:0.1%~0.5%、
Mn:0.8%~1.9%、
Nb:0.020%~0.10%、
を含有し、
P :0.05%以下、
S :0.01%以下、
Al:0.1%以下、
に制限し、
残部がFe及び不可避的不純物からなり、
(式1)によって求められる炭素等量Ceqが0.25~0.40であり、[X]を、質量%で表した元素Xの含有量としたとき、
[Nb]×[C]≧0.002が満足され、
前記二相組織鋼管の金属組織組成が、面積率で、80%~98%のフェライトと、合計2%~20%のマルテンサイト、残留オーステナイト、またはこれらの混合相と、を含み、
前記フェライトの平均粒径が1μm以上8μm未満であり、前記マルテンサイト、前記残留オーステナイト、または前記混合相の平均粒径が0.1μm以上2μm以下であることを特徴とする二相組織鋼管。
Ceq=[C]+[Mn]/6 ・・・ (式1)
ここで、[X]は、質量%で表した元素Xの含有量を表す。 - 前記二相組織鋼管の化学組成が、質量%で、
V :0.0001%~0.02%、
Ti:0.005%~0.03%、
Ca:0.001%~0.010%、
N :0.001%~0.01%、
の1種又は2種以上を更に含有し、
[X]を、元素Xの含有量[質量%]としたとき、
[V]/[Nb]≦1/3
が満足され、
前記炭素等量Ceqが前記(式1)に代わって、(式2)と定義されることを特徴とする、請求項1に記載の二相組織鋼管。
Ceq=[C]+[Mn]/6+[V]/5 ・・・ (式2)
ここで、[X]は、質量%で表した元素Xの含有量を表す。 - 前記二相組織鋼管の化学組成のNb含有量が0.040%~0.10%であり、
[X]を、質量%で表した元素Xの含有量としたとき、
[Nb]×[C]≧0.003を満足することを特徴とする請求項1又は2に記載の二相組織鋼管。 - 前記二相組織鋼管の板厚が5mm~15mmであることを特徴とする請求項1又は2に記載の二相組織鋼管。
- 化学組成が、質量%で、
C :0.07%~0.15%、
Si:0.1%~0.5%、
Mn:0.8%~1.9%、
Nb:0.020%~0.10%、
を含有し、
P :0.05%以下、
S :0.01%以下、
Al:0.1%以下、
に制限し、
残部がFe及び不可避的不純物からなり、
(式3)によって求められる炭素等量Ceqが0.25~0.40であり、[X]を、質量%で表した元素Xの含有量としたとき、
[Nb]×[C]≧0.002が満足される鋼材を用いて、
フェライトの平均粒径が1μm以上10μm未満となる条件で熱間圧延して、熱間圧延鋼板を製造する工程と、
前記熱間圧延鋼板から鋼管を造管する工程と、
前記鋼管を、オーステナイト変態の開始温度Ac1超、オーステナイト変態終了温度Ac3未満に加熱し、焼入れ処理する工程と、
を有することを特徴とする二相組織鋼管の製造方法。
Ceq=[C]+[Mn]/6 ・・・ (式3)
ここで、[X]は、質量%で表した元素Xの含有量を表す。 - 前記鋼材の化学組成が、質量%で、
V :0.0001%~0.02%、
Ti:0.005%~0.03%、
Ca:0.001%~0.010%、
N :0.001%~0.01%、
の1種又は2種以上を更に含有し、
[X]を、元素Xの含有量[質量%]としたとき、
[V]/[Nb]≦1/3
が満足され、
前記炭素等量Ceqが前記(式3)に代わって、(式4)と定義されることを特徴とする、請求項7に記載の二相組織鋼管の製造方法。
Ceq=[C]+[Mn]/6+[V]/5 ・・・ (式4)
ここで、[X]は、質量%で表した元素Xの含有量を表す。
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WO2014051119A1 (ja) * | 2012-09-27 | 2014-04-03 | 新日鐵住金株式会社 | 電縫溶接鋼管 |
WO2018042522A1 (ja) * | 2016-08-30 | 2018-03-08 | 新日鐵住金株式会社 | エクスパンダブルチューブラー用油井管 |
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EP3530365A4 (en) | 2016-10-18 | 2020-07-08 | Nippon Steel Corporation | METHOD OF PREDICTING CRUSHING RESISTANCE |
US11508490B2 (en) | 2020-03-11 | 2022-11-22 | Henry Crichlow | Managing volatiles in nuclear waste vitrification |
CN112553519B (zh) * | 2020-11-13 | 2021-12-10 | 柳州钢铁股份有限公司 | 低屈强比低成本高性能建筑结构用q420gj中厚钢板的制造方法 |
CN116732297B (zh) * | 2023-08-16 | 2023-10-20 | 中北大学 | 一种含铌高强双相钢及其制备方法和应用 |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2000144329A (ja) * | 1998-11-13 | 2000-05-26 | Kawasaki Steel Corp | 強度一延性バランスに優れた鋼管 |
JP2005002385A (ja) * | 2003-06-10 | 2005-01-06 | Sumitomo Metal Ind Ltd | 成形性と靱性に優れた鋼管とその製造方法 |
Family Cites Families (6)
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---|---|---|---|---|
JPH07150247A (ja) * | 1993-11-30 | 1995-06-13 | Nkk Corp | 建築用高強度低降伏比鋼管の製造方法 |
JPH07188748A (ja) * | 1993-12-27 | 1995-07-25 | Nkk Corp | 建築用高強度低降伏比鋼管の製造方法 |
US5755895A (en) * | 1995-02-03 | 1998-05-26 | Nippon Steel Corporation | High strength line pipe steel having low yield ratio and excellent in low temperature toughness |
CA2490700C (en) | 2002-06-19 | 2014-02-25 | Nippon Steel Corporation | Oil country tubular goods excellent in collapse characteristics after expansion and method of production thereof |
US8815024B2 (en) | 2004-02-19 | 2014-08-26 | Nippon Steel & Sumitomo Metal Corporation | Steel plate or steel pipe with small occurrence of Bauschinger effect and methods of production of same |
WO2009014238A1 (ja) | 2007-07-23 | 2009-01-29 | Nippon Steel Corporation | 変形特性に優れた鋼管及びその製造方法 |
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Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2000144329A (ja) * | 1998-11-13 | 2000-05-26 | Kawasaki Steel Corp | 強度一延性バランスに優れた鋼管 |
JP2005002385A (ja) * | 2003-06-10 | 2005-01-06 | Sumitomo Metal Ind Ltd | 成形性と靱性に優れた鋼管とその製造方法 |
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---|
See also references of EP2594655A4 * |
Cited By (7)
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WO2014051119A1 (ja) * | 2012-09-27 | 2014-04-03 | 新日鐵住金株式会社 | 電縫溶接鋼管 |
JP5516834B1 (ja) * | 2012-09-27 | 2014-06-11 | 新日鐵住金株式会社 | 電縫溶接鋼管 |
CN104350168A (zh) * | 2012-09-27 | 2015-02-11 | 新日铁住金株式会社 | 电阻焊钢管 |
EP2902519A4 (en) * | 2012-09-27 | 2016-06-01 | Nippon Steel & Sumitomo Metal Corp | RESISTANT WELDED STEEL TUBE |
US9726305B2 (en) | 2012-09-27 | 2017-08-08 | Nippon Steel & Sumitomo Metal Corporation | Electric resistance welded steel pipe |
WO2018042522A1 (ja) * | 2016-08-30 | 2018-03-08 | 新日鐵住金株式会社 | エクスパンダブルチューブラー用油井管 |
JPWO2018042522A1 (ja) * | 2016-08-30 | 2019-03-28 | 新日鐵住金株式会社 | エクスパンダブルチューブラー用油井管 |
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EP2594655A1 (en) | 2013-05-22 |
EP2594655B1 (en) | 2018-09-05 |
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