EP0224591A1 - Procede de production de tuyaux en acier haute resistance sans soudure presentant une excellente resistance aux fissures de corrosion sous contraintes dues aux sulfures - Google Patents

Procede de production de tuyaux en acier haute resistance sans soudure presentant une excellente resistance aux fissures de corrosion sous contraintes dues aux sulfures

Info

Publication number
EP0224591A1
EP0224591A1 EP86903563A EP86903563A EP0224591A1 EP 0224591 A1 EP0224591 A1 EP 0224591A1 EP 86903563 A EP86903563 A EP 86903563A EP 86903563 A EP86903563 A EP 86903563A EP 0224591 A1 EP0224591 A1 EP 0224591A1
Authority
EP
European Patent Office
Prior art keywords
stress corrosion
corrosion cracking
sulfide stress
resistance
strength
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP86903563A
Other languages
German (de)
English (en)
Other versions
EP0224591B1 (fr
EP0224591A4 (fr
Inventor
Kuniaki Kawasaki Steel Corporation Motoda
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
JFE Steel Corp
Original Assignee
Kawasaki Steel Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kawasaki Steel Corp filed Critical Kawasaki Steel Corp
Publication of EP0224591A1 publication Critical patent/EP0224591A1/fr
Publication of EP0224591A4 publication Critical patent/EP0224591A4/fr
Application granted granted Critical
Publication of EP0224591B1 publication Critical patent/EP0224591B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • 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
    • 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

Definitions

  • the present invention relates to a method of producing a high strength seamless steel pipe with a superior resistance against sulfide stress corrosion cracking.
  • the steel pipe is favorably used for oil well pipes under souring tendency and extremely deepening well, line pipes for sour gas and sour oil, chemical plant pipe lines, etc.
  • the invention discloses development outcomes to effectively avoid dangers of occurrence of sulfide stress corrosion cracks under a high yield strength of at least 75 kgf/mm 2 .
  • Cr-Mo base steel having a yield strength of around 64 to 74 kgf/mm 2 has been to date considered to be most excellent against the above-mentioned oil well deepening and souring tendency to attain both the properties in combination.
  • Japanese patent application laid-open Nos. 57-19,322 and 57-19,323 proposed La-added steels excellent in sulfide stress corrosion cracking-resistance, but the yield strength of these steels is around 80 kgf/mm 2 at the maximum. Therefore the strength is hardly improved when compared with the conventional steels.
  • Japanese patent application laid-open No. 57-35,622 discloses a high strength oil well steel in which P and S are reduced.
  • the strength of this steel is considerably improved, the stress corrosion cracking-resistance is assured only when H 2 S is contained in a small amount under an alkaline environment.
  • Japanese patent application laid-open Nos. 52-52,114 and 54-119,324 propose steels in which the sulfide stress corrosion cracking-resistance is improved through making steel grains finer by performing heating at the average heating rate of 3 to 50°C/s in a range of A Cl transformation point or higher (Japanese patent application laid-open No. 52-52,114) or rapidly performing cooling at about from 1 to 50°C/s (Japanese patent application laid-open No. 54-119,324) for quenching.
  • Japanese patent application laid-open Nos. 52-52,114 and 54-119,324 propose steels in which the sulfide stress corrosion cracking-resistance is improved through making steel grains finer by performing heating at the average heating rate of 3 to 50°C/s in a range of A Cl transformation point or higher (Japanese patent application laid-open No. 52-52,114) or rapidly performing cooling at about from 1 to 50°C/s (Japanese patent application laid-open No. 54
  • the yield strength of the steel disclosed in Japanese patent appliation laid-open No. 54-119,324 is about 65 kgf/mm 2
  • the maximum load stress at which no sulfide stress corrosion cracks occur is only 55 kgf/mm 2 (73% of the yield strength) when the yield strength is 75 kgf/mm 2 and only about 40 kgf/mm 2 (44% of the yield strength) when the yield strength is 90 kgf/m m 2.
  • An object of the present invention is to advantageously solve the above-mentioned problems, and to provide a process for advantageously producing a seamless steel pipe which is composed of inexpensive ingredients suitable for continuous casting without containing a large amount of the above-mentioned expensive elements and which has an excellent sulfide stress corrosion cracking-resistance and a high yield strength of from 75 to 120 kgf/mm 2 in combination.
  • the average cooling rate is set at not less than l°C/s in a range from the heating temperature to around 300°C at which the martensite transformation is almost completed.
  • the average cooling rate is set at not more than 50°C/s.
  • the present invention is based on the above-mentioned acknowledgement.
  • the present invention relates to a process for manufacturing a high strength seamless steel pipe having an excellent sulfide stress corrosion cracking-resistance, which process comprises hot processing a hollow raw material for the seamless steel pipe, heating the hot processed raw material up to a temperature of not less than an Ac 3 transformation point, quenching the resultant while cooling at the average cooling rate of from 1 to 50°C/s is done in a range from the A C2 transformation point to at least 300°C, thereby making conversion into martensite structure, and then annealing a quenched article in a temperature range of from not less than 680°C to not more than the Ac 3 transformation point, said raw material containing from more than 40 to 0.60% of C, from 0.20 to 0.35% of Si, from 0.4 to 1.2% of Mn, from 0.8 to 1.5% of Cr, from 0.6 to 1.0% of Mo, and from 0.005 to 0.1% of Al together with P and S being restricted to not more than 0.020% and not more than 0.010%, respectively, and occasionally further
  • C is an element useful for obtaining a high strength in quenching even at high temperatures.
  • at least more than 0.40% of C is necessary. If it exceeds 0.60%, there is possibility that quenching cracks occur.
  • C is added in a range from more than 0.40 to 0.60%.
  • At least 0.20% of Si is necessary to improve deoxidation and strength of the steel. If it exceeds 0.35%, the toughness is deteriorated. Thus, Si is restricted to a range from 0.20 to 0.35%.
  • Mn is an element useful for improving hardenability and strength as well as for deoxidizing. If the content is less than 0.4%, effect obtained by the addition is poor, while if it exceeds 1.2%, it causes segregation of P, S, etc. to deteriorate the sulfide stress corrosion cracking-resistance. Thus, Mn is included in a range from 0.4 to 1.2%.
  • Cr forms carbides during quenching and annealing treatment to effectively contribute to increase strength and annealing resistance.
  • Cr is restricted to a range from 0.8 to 1. 5%.
  • Mo increases strength and resistance against annealing and further effectively contributes to the improvement of the sulfide stress corrosion cracking-resistance through preventing the segregation of P in grain boundaries. If the content is less than 0.6%, effect obtained through the addition is poor. On the other hand, even if it is included at more than 1.0%, its effect is not only saturated, but also toughness tends to be inversely deteriorated and cost rises. Thus, Mo is restricted to a range from 0.6 to 1.0%.
  • Al is a useful element which not only contributes to deoxidation but also improves toughness, strength and sulfide stress corrosion cracking-resistance through making crystal grains fine upon reaction with N.
  • the content is less than 0.005%, the effect obtained through the addition is poor, while if it is over 0.1%, the effect is not only saturated, but also the toughness is inversely deteriorated. Thus, the content is restricted to 0.005 to 0.1%.
  • Both P and S are harmful elements which cause conspicuous deterioration of the sulfide stress corrosion cracking-resistance of the steel.
  • the annealing temperature is set at a high temperature of 680°C or more according to the present invention, it is necessary that P and S are restrained to not more than 0.020% and not more than 0.010%, respectively.
  • a molten steel formulated in the above-mentioned preferable ingredient composition is cast, and converted to a hollow material through piercing according to a conventional way.
  • the thus obtained hollow material for a seamless steel pipe is hot rolled, and then quenched and annealed.
  • the reason why the average cooling rate is restricted to the range from 1 to 50°C/s is that if the average cooling rate is slower than 1 0 C/s, the steel is not sufficiently quenched and therefore satisfactory sulfide stress corrosion cracking-resistance after the annealing cannot be obtained, while if it exceeds 50°C/s, there is a great possibility that quenching cracks occur.
  • a cooling way various methods are available, for instance, a method of applying a cooling medium to the steel pipe through spraying, showering, fogging, or the like while an amount of the cooling medium, the application pressure, etc. are controlled, a method of cooling the steel pipe with water or oil after the heating in the state that the pipe is preliminarily wrapped with an excellent thermal resistant and excellent temperature-maintaining refactory material prior to the heating, or a method of formulating such a cooling medium as to meet the intended cooling capability. Any method may be adapted so long as the average cooling rate in the above range is satisfied.
  • the high strength seamless steel pipe having excellent sulfide stress corrosion cracking-resistance can be obtained.
  • Ti, Nb and V may be added.
  • Ti, Nb and V all form carbides as in the case with Cr and Mo during the quenching and annealing treatment, and effectively contribute to the enhancement of the quenchability and resistance against the annealing- softening.
  • the addition amount exceeds 0.1%, the precipitates not only become coarse, but also the sulfide stress corrosion cracking-resistance is inversely deteriorated and further the processability and toughness become lowered.
  • Ti, Nb and V be added in a range of not more than 0.1% either when singly added or when added in combination.
  • the sulfide stress corrosion cracks are thought to be a kind of hydrogen brittleness in which hydrogen generated by the corrosion of the steel with an aqueous solution containing hydrogen sulfide penetrates into the steel and gathers at stress- concentrating locations of the inclusions, precipitates, transformations etc. to embrittle the steel.
  • the stress- concentrating locations at which hydrogen gathers are thought to be conspicuously reduced by reducing P and S, decreasing the inclusions, decreasing transformation density and making the precipitates spherical through annealing at high temperatures of not less than 680°C, and obtaining structure in which the precipitates are finely and uniformly distributed through annealing at high temperatures after not less than 90% is converted to martensite.
  • the strength of the steel becomes lower. According to the ingredient combination of the present invention, however, it is considered that the tissues having the precipitates with appropriate profile and distribution can be obtained so that the high strength can be obtained without deteriorating the sulfide stress corrosion cracking-resistance.
  • a seamless steel pipe hollow material having an ingredient composition shown in Table 1 was hot processed, heated up to the Ac 3 transformation point, cooled at the average cooling rate shown in Table 1, and then subjected to an annealing treatment at a temperature given in Table 1, thereby obtaining a product.
  • the sulfide stress corrosion cracking-resistance was evaluated by a test in which a stress being 80% of the yield strength was loaded while a round bar tensile test piece was immersed into an NACE liquid (0.5% acetic acid, and saturated hydrogen sulfide aquoues solution containing 5% of sodium chloride). "o" mark and "x” mark show non-broken samples and broken samples in the test for 30 days, respectively.
  • the seamless steel pipe which is composed of an inexpensive ingredient system containing no great amount of expensive elements unlike the prior art and suitable for the continuous casting and which has the high strength of the yield strength of from 75 to 120 kgf/mm 2 and is free from the development of the sulfide stress corrosion cracks under the load stress of 80% of the yielding stress.
  • the present invention is advantageously suited particularly for the oil well pipes and line pipes for souring gas and souring oil under the tendency that the wells become deeper under the stronger souring and further pipe lines for the chemical plant.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Heat Treatment Of Articles (AREA)
  • Heat Treatment Of Steel (AREA)

Abstract

Procédé permettant de produire des tuyaux en acier sans soudure destinés dans les puits de pétrole, les canalisations, les installations chimiques, etc., ayant à la fois une excellente résistance mécanique et une excellente résistance aux fissures de corrosion sous contraintes dues aux sulfures, en utilisant des composants peu coûteux, lequel procédé consiste à augmenter la teneur en C et à réduire au minimum les teneurs en impuretés telles que P et S, à exécuter une trempe à une cadence relativement faible comprise entre 1 et 50oC/s après le traitement thermique, puis à effectuer un revenu dans une plage thermique relativement élevée comprise entre 680oC et le point critique Ac1. Le tuyau ainsi obtenu présente une limite élastique de 75 kgf/mm2 ou plus et une excellente résistance aux fissures de corrosion sous contraintes sans provoquer de tapure de trempe.
EP86903563A 1985-05-23 1986-05-22 Procede de production de tuyaux en acier haute resistance sans soudure presentant une excellente resistance aux fissures de corrosion sous contraintes dues aux sulfures Expired - Lifetime EP0224591B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP10923185 1985-05-23
JP109231/85 1985-05-23

Publications (3)

Publication Number Publication Date
EP0224591A1 true EP0224591A1 (fr) 1987-06-10
EP0224591A4 EP0224591A4 (fr) 1989-03-22
EP0224591B1 EP0224591B1 (fr) 1993-08-18

Family

ID=14504936

Family Applications (1)

Application Number Title Priority Date Filing Date
EP86903563A Expired - Lifetime EP0224591B1 (fr) 1985-05-23 1986-05-22 Procede de production de tuyaux en acier haute resistance sans soudure presentant une excellente resistance aux fissures de corrosion sous contraintes dues aux sulfures

Country Status (4)

Country Link
EP (1) EP0224591B1 (fr)
JP (1) JPS6254021A (fr)
DE (1) DE3688906T2 (fr)
WO (1) WO1986007096A1 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0461734A1 (fr) * 1990-06-12 1991-12-18 MANNESMANN Aktiengesellschaft Procédé pour améliorer la résistance à la fissuration par corrosion sous tension induite par hydrogène d'articles en acier
EP0787541A1 (fr) * 1994-10-20 1997-08-06 Sumitomo Metal Industries, Ltd. Procede de production de tubes d'acier sans soudure et materiel de production afferent
CN104968808A (zh) * 2013-01-31 2015-10-07 杰富意钢铁株式会社 韧性优异的无缝钢管的制造方法及制造设备
AU2014294435B2 (en) * 2013-07-26 2017-07-06 Nippon Steel Corporation Low alloy oil well steel pipe and method for manufacturing same

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5085733A (en) * 1989-08-24 1992-02-04 Nippon Seiko Kabushiki Kaisha Rolling steel bearing
JPH06128628A (ja) * 1992-10-16 1994-05-10 Toyota Motor Corp 高強度中空鋼管の製造方法
GB0216074D0 (en) 2002-07-11 2002-08-21 Weatherford Lamb Improving collapse resistance of tubing
JP4609138B2 (ja) * 2005-03-24 2011-01-12 住友金属工業株式会社 耐硫化物応力割れ性に優れた油井管用鋼および油井用継目無鋼管の製造方法
AU2015361346B2 (en) 2014-12-12 2019-02-28 Nippon Steel Corporation Low-alloy steel for oil well pipe and method for manufacturing low-alloy steel oil well pipe

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3992231A (en) * 1975-05-01 1976-11-16 Amax Inc. Temper-stressed oil well casing
EP0064730A2 (fr) * 1981-05-08 1982-11-17 Lone Star Steel Company Tubages ayant des caractéristiques mécaniques élevées pour applications critiques dans les champs pétrolifères et procédé pour leur fabrication
JPS589918A (ja) * 1981-07-11 1983-01-20 Kawasaki Steel Corp 耐硫化物応力腐食割れ性に優れた鋼管の製造方法

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5974221A (ja) * 1982-10-19 1984-04-26 Kawasaki Steel Corp 高強度継目無鋼管の製造方法

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3992231A (en) * 1975-05-01 1976-11-16 Amax Inc. Temper-stressed oil well casing
EP0064730A2 (fr) * 1981-05-08 1982-11-17 Lone Star Steel Company Tubages ayant des caractéristiques mécaniques élevées pour applications critiques dans les champs pétrolifères et procédé pour leur fabrication
JPS589918A (ja) * 1981-07-11 1983-01-20 Kawasaki Steel Corp 耐硫化物応力腐食割れ性に優れた鋼管の製造方法

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
IRON AND STEEL INTERNATIONAL, vol. 57, no. 1, February 1984, pages 16-21, Whitstable, Kent, GB; M. TANIMURA: "Oil country tubular goods for sour oil and gas service" *
See also references of WO8607096A1 *

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0461734A1 (fr) * 1990-06-12 1991-12-18 MANNESMANN Aktiengesellschaft Procédé pour améliorer la résistance à la fissuration par corrosion sous tension induite par hydrogène d'articles en acier
EP0787541A1 (fr) * 1994-10-20 1997-08-06 Sumitomo Metal Industries, Ltd. Procede de production de tubes d'acier sans soudure et materiel de production afferent
EP0787541A4 (fr) * 1994-10-20 1999-02-10 Sumitomo Metal Ind Procede de production de tubes d'acier sans soudure et materiel de production afferent
CN104968808A (zh) * 2013-01-31 2015-10-07 杰富意钢铁株式会社 韧性优异的无缝钢管的制造方法及制造设备
AU2014294435B2 (en) * 2013-07-26 2017-07-06 Nippon Steel Corporation Low alloy oil well steel pipe and method for manufacturing same

Also Published As

Publication number Publication date
WO1986007096A1 (fr) 1986-12-04
DE3688906T2 (de) 1993-12-09
JPS6254021A (ja) 1987-03-09
EP0224591B1 (fr) 1993-08-18
DE3688906D1 (de) 1993-09-23
EP0224591A4 (fr) 1989-03-22

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