EP2322679B1 - Tuyau continu en acier inoxydable martensitique pour un tuyau de puits de pétrole et processus de production associé - Google Patents

Tuyau continu en acier inoxydable martensitique pour un tuyau de puits de pétrole et processus de production associé Download PDF

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EP2322679B1
EP2322679B1 EP08876878.3A EP08876878A EP2322679B1 EP 2322679 B1 EP2322679 B1 EP 2322679B1 EP 08876878 A EP08876878 A EP 08876878A EP 2322679 B1 EP2322679 B1 EP 2322679B1
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stainless steel
temperature
content
martensitic stainless
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EP2322679A4 (fr
EP2322679A1 (fr
Inventor
Kenichiro Eguchi
Yukio Miyata
Mitsuo Kimura
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JFE Steel Corp
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JFE Steel Corp
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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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/26—Ferrous alloys, e.g. steel alloys containing chromium with niobium or tantalum
    • 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
    • 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
    • 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
    • C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
    • 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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/48—Ferrous alloys, e.g. steel alloys containing chromium with nickel with niobium or tantalum

Definitions

  • the present invention relates to a martensitic stainless steel seamless tube for oil country tubular goods, and more particularly to a seamless steel tube for OCTG which possesses both of high strength of 655 MPa in terms of yield strength (YS) and excellent low-temperature toughness, and a manufacturing method thereof.
  • a steel tube for an oil well used in such a severe environment is required to be made of a material which possesses high strength, excellent corrosion resistance and excellent toughness.
  • JP-A-2002-363708 proposes martensitic stainless steel which contains 0.01 to 0.1% of C, 9 to 15% of Cr and 0.1% or less of Ni. Although the stainless steel exhibits relatively high C content so that the stainless steel possesses high strength, the stainless steel possesses high toughness. Accordingly, the stainless steel is preferably used for manufacturing oil country tubular goods.
  • JP-A-2002-363708 it is estimated that by reducing a quantity of carbide present in a prior austenite grain boundary to 0.5 volume% or less, by setting a maximum minor axis of carbide to 10 to 200 nm and by setting a ratio between average Cr concentration and average Fe concentration in carbide to 0.4 or less, the precipitation of M 23 C 6 -type carbide is suppressed and the precipitation of M 3 C-type carbide is accelerated thus largely improving toughness.
  • the stainless steel is subject to tempering at a temperature of 450°C or below in such a manner that the stainless steel is subject to air cooling (standing to cool) after hot working, is held in air cooling (standing to cool) after solution treatment, or is subject to air cooling (standing to cool) after solution treatment.
  • the present invention has been made to overcome such drawbacks of the prior art, and it is an object of the present invention to provide a seamless steel tube for OCTG which possesses both of high strength of yield strength YS of 95 ksi grade (655 to 758 MPa) or more and excellent low-temperature toughness, and a method of manufacturing the seamless steel; tube in a stable manner.
  • excellent low-temperature toughness implies a case where a fracture transition temperature vTrs in a Charpy impact test is -40°C or below.
  • JP 2003 071589 A discloses a manufacturing method for a high strength oil well pipe by welding joining.
  • the welding joining is conducted using a GTAW method of GMAW method.
  • the welding material is preferably made to contain REM as the essential containment.
  • the gist of the present invention lies in the followings.
  • the present invention hot straitening can be realized. Accordingly, even when straitening is performed, the increase of yield strength is small so that it is possible to manufacture easily and stably a seamless steel tube for OCTG which possesses both of high strength of yield strength YS of 655 to 758 MPa and excellent low-temperature toughness where a fracture transition temperature vTrs is -40°C or below thus acquiring remarkable industrial advantageous effects.
  • Inventors of the present invention to realize the above-mentioned object, have extensively studied the influence of content composition and heat treatment conditions exerted on a change of toughness brought about by increasing strength of a 13Cr martensitic stainless steel tube.
  • the inventors have found that it is possible to prevent the deterioration of toughness attributed to grain boundary precipitation of M 23 C 6 type Cr-based carbide by adopting a chemical content system as specified in claim 1, in which a C content is limited to 0.02% or less, a Cr content is set to a value which falls within approximately 10% to 14% Cr where corrosion resistance is not deteriorated, Ni content is set to a relatively low value of 3% or less, and a relatively large quantity of, that is, 0.03% or more of Nb is contained in the content system.
  • a straitening temperature can be set to a high temperature of 450°C or more and hence, the increase of yield strength YS after straitening is decreased to 15 MPa or less.
  • the present invention has been completed by further continuing studies based on the above-mentioned findings.
  • the seamless steel tube for OCTG according to the present invention is a martensitic stainless steel seamless tube which adopts the composition as specified in the following:
  • C is an important element relating to strength of martensitic stainless steel.
  • the stainless steel contains 0.003% or more of C to ensure desired high strength, when a content of C exceeds 0.020%, toughness and also corrosion resistance are liable to be lowered. Accordingly, in the present invention, the content of C is limited to 0.020% or less. From a view point of stable assuring of strength and toughness, the content of C is preferably limited to a value which falls within a range from 0.003% to 0.015%.
  • Cr is an element which enhances corrosion resistance due to the formation of a protective film, and is an element which effectively contributes to the enhancement of CO 2 corrosion resistance and CO 2 stress corrosion cracking resistance.
  • the stainless steel contains 10% or more of Cr, the stainless steel can ensure required corrosion resistance as oil country tubular goods and hence, 10% is set to a lower limit of Cr content in the present invention.
  • the stainless steel contains a large quantity of Cr exceeding 14%, ferrite is easily formed so that the addition of a large quantity of expensive austenite forming element becomes necessary for ensuring stability of a martensite phase or for preventing the lowering of hot workability whereby the content of Cr exceeding 14% is economically disadvantageous.
  • the content of Cr is limited to a value which falls within a range from 10 to 14%. From a view point of ensuring the more stable structure and the more stable hot workability, the content of Cr is preferably limited to a value which falls within a range from 10.5 to 11.5%.
  • Ni is an element which has a function of strengthening a protective film, and enhances corrosion resistance such as CO 2 corrosion resistance. Although it is desirable that the stainless steel tube contains 0.1% or more of Ni to acquire such an advantageous effect, when the content of Ni exceeds 3%, this leads to only a sharp rise of a manufacturing cost. Accordingly, the content of Ni is limited to a value which falls within a range not more than 3%. The content of Ni is preferably limited to a value which falls within a range from 1.5 to 2.5%.
  • N is an element which remarkably enhances pitting corrosion resistance, and such an advantageous effect becomes outstanding when the content of N becomes 0.003% or more.
  • the content of N exceeds 0.05%, various nitrides are formed thus lowering toughness. Accordingly, the content of N is limited to 0.05% or less.
  • the content of N is preferably limited to a value which falls within a range from 0.01 to 0.02%.
  • Nb is an important element in the present invention.
  • Nb is an element which forms a carbide, and increases strength of steel through precipitation strengthening by Nb carbide. Further, in the present invention, Nb plays an important role for preventing the grain boundary precipitation of M 23 C 6 type Cr carbide thus enhancing toughness. To acquire such an advantageous effect, it is necessary to set the content of Nb to 0.03% or more, and more preferably to a value which exceeds 0.03%. Further, from a view point of acquiring higher strengthening and higher toughness, the content of Nb is set to 0.06% or more. On the other hand, when the content of Nb exceeds 0.2%, toughness is lowered. Accordingly, the content of Nb is limited to a value which falls within a range from 0.06 to 0.2%. The content of Nb is preferably limited to a value which falls within a range from 0.06 to 0.15%.
  • Si is an element which functions as deoxidizing agent in a usual steel making process. Although it is desirable to set the content of Si to 0.1% or more, when the content of Si exceeds 1.0%, toughness is lowered and cold workability property is also lowered. Accordingly, the content of Si is limited to 1.0% or less. The content of Si is preferably limited to a value which falls within a range from 0.1 to 0.3%.
  • Mn is an element which increases strength of the stainless steel.
  • the content of Mn is 0.1% or more to allow the stainless steel to ensure strength necessary for a steel tube for oil country tubular goods
  • toughness is adversely influenced by Mn. Accordingly, the content of Mn is limited to a value which falls within a range from 0.1 to 2.0%.
  • the content of Mn is preferably limited to a value which falls within a range from 0.5 to 1.5%.
  • P is an element which deteriorates corrosion resistance such as CO 2 corrosion resistance and hence, it is desirable to reduce the content of P as much as possible in the present invention.
  • the extreme reduction of the content of P pushes up a manufacturing cost.
  • the content P is limited to 0.020% or less.
  • the content of P is preferably limited to 0.015% or less.
  • S is an element which remarkably deteriorates hot workability in a tube manufacturing step. Although it is desirable to decrease the content of S as much as possible, the tube can be manufactured in a usual step by decreasing the content of S to 0.010% or less and hence, the content of S is limited to 0.010% or less. Here, the content of S is preferably limited to 0.003% or less.
  • Al is an element which possesses a strong deoxidizing action. To acquire such an advantageous effect, it is desirable that the stainless steel contains 0.001% or more of Al. However, when the content of Al exceeds 0.10%, Al adversely influences toughness. Accordingly, the content of Al is limited to 0.10% or less. The content of Al is preferably limited to 0.05% or less.
  • the content of Nb falls within the above-mentioned content range and, further, a following formula (1) is satisfied in view of the relationship between the content Nb and the contents of C, Al and N.
  • the stainless steel cannot possess both of desired high strength (yield strength: 655 MPa or more) and high toughness (fracture transition temperature vTrs in a Charpy impact test is -40°C or below).
  • the stainless steel may include one or two kinds of components in a group A and a group B described hereinafter.
  • Both Cu and Mo are elements which have a function of enhancing corrosion resistance and the stainless steel may selectively contain these elements when necessary.
  • Cu is an element which has a function of strengthening a protective film thus enhancing pitting resistance, and it is desirable to set the content of Cu to 0.2% or more to acquire such an advantageous effect.
  • the content of Cu exceeds 2.0%, Cu or a part of Cu compound precipitates thus lowering toughness.
  • the content of Cu is preferably limited to 2.0% or less.
  • the content of Cu is more preferably limited to a value which falls within a range from 0.2 to 1.0%.
  • Mo is an element which has a function of increasing resistance against pitting by Cl - , and it is desirable to set the content of Mo to 0.2% or more to acquire such an advantageous effect.
  • the content of Mo exceeds 2.0%, the strength of the stainless steel is lowered and, at the same time, a manufacturing cost sharply rises. Accordingly, the content of Mo is preferably limited to 2.0% or less.
  • the content of Mo is more preferably limited to a value which falls within a range from 0.2 to 1.0%.
  • Group B one kind or two or more kinds selected from 0.20% or less V, 0.10% or less Ti, 0.005% or less B.
  • V, Ti and B are elements which increase strength of the stainless steel, and the stainless steel may selectively contain one kind or two or more kinds of these elements when necessary.
  • the stainless steel contains 0.02 or more V, 0.02% or more Ti, 0.0015% or more B.
  • V exceeds, 0.20%
  • Ti exceeds 0.10%
  • B exceeds 0.005%
  • toughness is lowered.
  • the stainless steel contains these elements, it is desirable to set the content of V to 0.20 or less, the content of Ti to 0.10% or less, and the content of B to 0.005% or less. It is more preferable to set the content of V to 0.02 to 0.10%, the content of Ti to 0.02 to 0.05%, and the content of B to 0.0015 to 0.0040%.
  • a balance of the stainless steel except for the above-mentioned components is formed of Fe and unavoidable impurities.
  • unavoidable impurities 0.010% or less of O is allowable.
  • the seamless steel tube for OCTG of the present invention has the structure which is mainly in a tempered martensite phase and in which precipitated Nb is dispersed.
  • the structure may contain 5 volume% or less of a delta ferrite and 5 volume% or less of austenite respectively.
  • the content of delta ferrite may preferably be set to 2 volume% or less.
  • the content of austenite may preferably be set to 2 volume% or less.
  • a precipitated Nb quantity is set to 0.020 mass% or more in terms of Nb.
  • the precipitated Nb quantity is preferably set to 0.025 mass % or more in terms of Nb.
  • the seamless steel tube for OCTG of the present invention does not contain M 3 c type Cr type carbide.
  • the precipitated Nb quantity is determined such that an electrolytic residue obtained by electrolytic extraction using an electrolytic extraction method is subject to a chemical analysis thus obtaining a quantity of Nb contained in the electrolytic residue, and the obtained quantity of Nb is used as the precipitated Nb quantity contained in a sample.
  • the precipitated Nb is mainly formed on Nb carbide or Nb carbonitride.
  • the precipitated Nb is a precipitated material having a spherical shape with an average particle size of 3 nm to 15 nm.
  • molten steel having the above-mentioned composition is produced by a usually known melting method such as a steel converter, an electric furnace, a vacuum melting furnace, a molten state is formed into a steel tube raw material such as billets by a usual method such as continuous casting, ingot casting or blooming method. Then, these steel tube material is heated and is formed into a seamless steel tube having a desired size by hot working using manufacturing steps of a usual Mannesmann-plug mill method or a usual Mannesmann-mandrel mill method, and the seamless steel tube is used as a starting raw material.
  • a seamless steel tube may be manufactured by hot extruding using a press method. Further, after forming the seamless steel tube, it is desirable to cool the seamless steel tube to a room temperature at a cooling rate of air cooling or more.
  • the starting material (seamless steel tube) is firstly subject to quenching.
  • Quenching in the present invention implies treatment in which the seamless steel tube is reheated to a quenching temperature of A c3 transformation temperature or above and, thereafter, the seamless steel tube is cooled to a temperature zone of 100°C or below from the quenching temperature at a cooling rate of air cooling or more. Due to such quenching, it is possible to form the structure of the starting material into the fine martensitic structure.
  • the quenching heating temperature is below the A c3 transformation temperature, the temperature of the seamless steel tube cannot be heated at a austenite single phase region so that the sufficient martensitic structure cannot be formed by cooling after heating and hence, the seamless steel tube cannot ensure desired strength (yield strength: 655 MPa or more). Accordingly, the heating temperature of quenching is limited to an A c3 transformation temperature or above.
  • the heating temperature is preferably set to 1000°C or below.
  • cooling from the quenching heating temperature is performed until a temperature zone of 100°C or below at a cooling rate of air cooling or more.
  • the starting material used in the present invention possesses the high quenching property and hence, when the starting material is cooled down to the temperature zone of 100°C or below at a cooling rate of approximately air cooling, the seamless steel tube can acquire the sufficient quenching structure (martensitic structure). Further, it is preferable to set a holding time of the starting material at the quenching temperature to 10 minutes or more from a viewpoint of homogeneous heating.
  • the seamless steel tube to which quenching is applied is subsequently subject to tempering.
  • tempering is important treatment for ensuring excellent low-temperature toughness.
  • the seamless steel tube is heated to a tempering temperature which is 550°C or more, and preferably A c1 transformation temperature or below, the heating is preferably held for 30 minutes or more and, thereafter, the seamless steel tube is cooled down preferably to a room temperature preferably at a cooling rate of air cooling or more. Due to such tempering, it is possible to produce the seamless steel tube which possesses both high strength of YS of 655 MPa or more and the excellent low-temperature toughness of vTrs of -40°C or below.
  • the temperature at straightening is set to a tempering temperature or above, the structure is changed and hence, there is no way but to set the temperature at straightening to the tempering temperature or below when the tempering temperature is less than 550°C. Accordingly, as described later, irregularities of yield strength YS are liable to occur.
  • the tempering temperature exceeds the A c1 transformation temperature, an austenite phase is formed and the austenite phase is transformed into quenched martensite at the time of cooling. Since the quenched martensite has many mobile dislocations, when the quenched martensite precipitates, yield strength YS is lowered. Further, from a viewpoint of acquiring the sufficient martensite, it is preferable to perform cooling from the tempering temperature at a cooling rate of air cooling or more.
  • straightening may be applied to the seamless steel tube for straightening the deformed steel tube shape following the tempering. It is preferable to perform straightening in a temperature zone of 450°C or above.
  • a working strain is locally generated in the steel tube at the time of performing straightening so that irregularities are liable to occur in mechanical properties, and particularly yield strength YS.
  • the straightening is performed within a temperature zone of 450°C or above.
  • the desired irregularities ( ⁇ YS) of yield strength YS in the present invention is 15 MPa or less.
  • the seamless steel tube manufactured by the above-mentioned manufacturing method is formed into the martensitic stainless steel seamless tube which has the above-mentioned composition and structure, and possesses high strength of yield strength of 655 MPa or more and the excellent low-temperature toughness of fracture transition temperature vTrs of -40°C or below in a Charpy impact test, and further possesses the sufficient corrosion resistance as the oil country tubular goods.
  • the molten steel having the composition shown in Table 1 is degassed and, thereafter, billets (size: 207 mm ⁇ ) are formed by casting by a continuous casting method and are used as steel tube materials . These steel tube materials are heated, and are formed into tubes by hot working through Mannesmann-method manufacturing steps and, thereafter, the tubes are air-cooled so as to form seamless steel tubes (outer diameter of 177.8 mm ⁇ ⁇ wall thickness of 12.65 mm).
  • Specimens are sampled from the obtained seamless steel tubes, and quenching and tempering are applied and optional straightening is further applied to the specimens (steel tubes) under conditions shown in Table 2 and Table 3.
  • Electrolytic extraction specimens are sampled from the specimens (steel tubes) to which quenching and tempering are applied and optional straightening is further applied. Using the sampled electrolytic extraction specimen, a quantity of Nb contained in an obtained electrolytic residue is obtained using an electrolytic extraction method and is determined as a quantity of precipitated Nb contained in the specimen.
  • a strip specimen specified by API standard 5CT is sampled, and a tensile test is carried out on the strip specimen thus obtaining tensile characteristics (yield strength YS, tensile strength TS) of the strip specimen.
  • a tensile test is carried out on the non-straightened steel tubes manufactured under the same condition except for straightening thus obtaining tensile characteristics (yield strength YS, tensile strength TS) of the strip specimens.
  • An increment ⁇ YS of YS by straightening is calculated by a following formula.
  • ⁇ ⁇ YS YS of strainghtened steel tube ⁇ YS of non-strainghtened steel tube
  • V-notch specimens (thickness: 10 mm) are sampled from specimens to which quenching and tempering are applied and optional straightening is further applied in accordance with the stipulation of JIS Z 2242.
  • the V-notch specimens are subject to a Charpy impact test where a fracture transition temperature vTrs is obtained and toughness is evaluated.
  • a corrosion specimen having a thickness of 3 mm, a width of 30 mm and a length of 40 mm is prepared by machining from the specimens, and a corrosion test is carried on the corrosion specimen.
  • the corrosion test is carried out in such a manner that the corrosion specimen is immersed into a test solution: 20% NaCl aqueous solution (temperature of the test solution: 80°C, under CO 2 gas atmosphere of 30 atmospheric pressure) held in an autoclave, and an test duration is 1 week (168h).
  • a corrosion rate is calculated based on the reduction of weight before and after the corrosion test.
  • All examples of the present invention are martensitic stainless steel seamless tubes which exhibit the sufficient corrosion resistance, possess both of high strength of YS of 655 MPa or more and excellent low-temperature toughness of vTrs of -40°C or less, and allows hot straightening at a temperature of 450°C or more so that an increment of yield strength is small and the difference ⁇ YS of the average YS is small (15 MPa or less) even when straightening is applied.
  • YS 655 MPa or more
  • vTrs of -40°C or less

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Claims (6)

  1. Tube sans soudure en acier inoxydable martensitique pour produits tubulaires de pays pétroliers possédant à la fois une résistance élevée de limite d'élasticité YS supérieure ou égale à 655 MPa et une excellente ténacité à basse température, où une température de transition de rupture vTrs lors d'un essai de choc Charpy est inférieure ou égale à -40 °C, le tube sans soudure ayant la composition contenant, en % en masse, 0,003 % ou plus et 0,020 % ou moins de C, 1,0 % ou moins de Si, 0,020 % ou moins de P, 0,010 % ou moins de S, 0,10 % ou moins d'Al, de 10 à 14 % de Cr, 3 % ou moins de Ni, de 0,06 à 0,2 % de Nb, 0,05 % ou moins de N, de 0,1 à 2,0 % de Mn, au moins un ou deux éléments, en tant qu'éléments facultatifs, choisis parmi 2,0 % ou moins de Cu et 2,0 % ou moins de Mo, au moins un, deux ou plusieurs éléments, en tant qu'éléments facultatifs, choisis parmi 0,20 % ou moins de V, 0,10 % ou moins de Ti et 0,005 % ou moins de B, et du fer et des impuretés inévitables en complément à cent, et ayant la structure où une quantité de Nb précipité est supérieure ou égale à 0,020 % en termes de Nb.
  2. Tube sans soudure en acier inoxydable martensitique pour produits tubulaires de pays pétroliers selon la revendication 1, le tube en acier sans soudure ayant la composition contenant ledit Nb de telle sorte qu'une formule (1) suivante soit satisfaite en termes de C, Al et N. C − 31 / 4 ⁢ Nb + 7 / 6 ⁢ N − 9 / 4 ⁢ Al ≤ 0,30
    Figure imgb0007
     (Ici, C, Nb, N, Al : teneurs des éléments respectifs en % en masse)
  3. Procédé de fabrication d'un tube sans soudure en acier inoxydable martensitique pour produits tubulaires de pays pétroliers, le procédé comprenant : une trempe, au cours de laquelle un tube sans soudure en acier inoxydable ayant la composition contenant, en % en masse, 0,003 % ou plus et 0,020 % ou moins de C, 1,0 % ou moins de Si, 0,020 % ou moins de P, 0,010 % ou moins de S, 0,10 % ou moins d'Al, de 10 à 14 % de Cr, 3 % ou moins de Ni, de 0,06 à 0,2 % de Nb, 0,05 % ou moins de N, de 0,1 à 2,0 % de Mn, au moins un ou deux éléments, en tant qu'éléments facultatifs, choisis parmi 2,0 % ou moins de Cu et 2,0 % ou moins de Mo, au moins un, deux ou plusieurs éléments, en tant qu'éléments facultatifs, choisis parmi 0,20 % ou moins de V, 0,10 % ou moins de Ti et 0,005 % ou moins de B, et du fer et des impuretés inévitables en complément à cent, est chauffé à une température de trempe supérieure ou égale à la température de transformation Ac3, après quoi le tube sans soudure est refroidi jusqu'à une plage de température de 100 °C ou moins depuis la température de trempe à une vitesse de refroidissement supérieure ou égale à un refroidissement à l'air libre ; et un revenu qui suit la trempe et au cours duquel le tube sans soudure est chauffé à une température de revenu supérieure ou égale à 550 °C et inférieure ou égale à la température de transformation Ac1 et refroidi.
  4. Procédé de fabrication d'un tube sans soudure en acier inoxydable martensitique pour produits tubulaires de pays pétroliers selon la revendication 3, dans lequel le tube sans soudure présente la composition contenant ledit Nb de telle sorte qu'une formule (1) suivante soit satisfaite en termes de C, Al et N. C − 31 / 4 ⁢ Nb + 7 / 6 ⁢ N − 9 / 4 ⁢ Al ≤ 0,30
    Figure imgb0008
     (Ici, C, Nb, N, Al : teneurs des éléments respectifs en % en masse)
  5. Procédé de fabrication d'un tube sans soudure en acier inoxydable martensitique pour produits tubulaires de pays pétroliers selon la revendication 3 ou 4, dans lequel un dressage est effectué dans une plage de température supérieure ou égale à 450 °C pendant le refroidissement après ledit revenu.
  6. Tube sans soudure en acier inoxydable martensitique pour produits tubulaires de pays pétroliers obtenu par le procédé de fabrication d'un tube sans soudure en acier inoxydable martensitique pour produits tubulaires de pays pétroliers selon la revendication 5, où un incrément ΔYS de la limite d'élasticité dû au dressage est inférieur ou égal à 15 MPa.
EP08876878.3A 2008-09-04 2008-12-24 Tuyau continu en acier inoxydable martensitique pour un tuyau de puits de pétrole et processus de production associé Active EP2322679B1 (fr)

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JP2008226578 2008-09-04
PCT/JP2008/073918 WO2010026672A1 (fr) 2008-09-04 2008-12-24 Tuyau continu en acier inoxydable martensitique pour un tuyau de puits de pétrole et processus de production associé

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EP2322679A1 EP2322679A1 (fr) 2011-05-18
EP2322679A4 EP2322679A4 (fr) 2016-11-30
EP2322679B1 true EP2322679B1 (fr) 2020-02-26

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US10246765B2 (en) * 2014-01-17 2019-04-02 Nippon Steel & Sumitomo Metal Corporation Martensitic Cr-containing steel and oil country tubular goods
CN107747063B (zh) * 2017-11-29 2019-08-23 郑州永通特钢有限公司 一种高强韧马氏体不锈钢
RU2686405C1 (ru) * 2017-12-04 2019-04-25 Публичное акционерное общество "Трубная металлургическая компания" (ПАО "ТМК") Способ изготовления труб нефтяного сортамента (варианты)
TW202006155A (zh) * 2018-07-18 2020-02-01 日商日本製鐵股份有限公司 鋼板
CN111154954A (zh) * 2020-02-11 2020-05-15 包头钢铁（集团）有限责任公司 一种含稀土高强高韧深井页岩气用无缝钢管热处理方法
CN115110010A (zh) * 2022-05-31 2022-09-27 天津钢管制造有限公司 140Ksi钢级非开挖钻杆用无缝钢管及其制备方法
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Publication number Publication date
RU2011112690A (ru) 2012-10-10
WO2010026672A1 (fr) 2010-03-11
RU2468112C1 (ru) 2012-11-27
US20110132501A1 (en) 2011-06-09
EP2322679A4 (fr) 2016-11-30
CN102144041B (zh) 2014-05-14
EP2322679A1 (fr) 2011-05-18
CN102144041A (zh) 2011-08-03

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