WO2002103069A1 - Tuyau en acier a haute formabilite, et procede de fabrication - Google Patents

Tuyau en acier a haute formabilite, et procede de fabrication Download PDF

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Publication number
WO2002103069A1
WO2002103069A1 PCT/JP2001/005053 JP0105053W WO02103069A1 WO 2002103069 A1 WO2002103069 A1 WO 2002103069A1 JP 0105053 W JP0105053 W JP 0105053W WO 02103069 A1 WO02103069 A1 WO 02103069A1
Authority
WO
WIPO (PCT)
Prior art keywords
steel pipe
temperature
steel
value
rolling
Prior art date
Application number
PCT/JP2001/005053
Other languages
English (en)
Japanese (ja)
Inventor
Takaaki Toyooka
Yoshikazu Kawabata
Akira Yorifuji
Masanori Nishimori
Motoaki Itadani
Takatoshi Okabe
Masatoshi Aratani
Original Assignee
Kawasaki Steel Corporation
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
Priority to JP2000019557A priority Critical patent/JP3794230B2/ja
Priority claimed from JP2000019557A external-priority patent/JP3794230B2/ja
Application filed by Kawasaki Steel Corporation filed Critical Kawasaki Steel Corporation
Priority to EP01938656A priority patent/EP1437422A4/fr
Priority to BRPI0110441-1B1A priority patent/BR0110441B1/pt
Priority to PCT/JP2001/005053 priority patent/WO2002103069A1/fr
Priority to US10/258,982 priority patent/US7591914B2/en
Priority to CNB018086209A priority patent/CN1234896C/zh
Priority to CA002403830A priority patent/CA2403830C/fr
Publication of WO2002103069A1 publication Critical patent/WO2002103069A1/fr

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
    • 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
    • B21C37/00—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
    • B21C37/06—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape of tubes or metal hoses; Combined procedures for making tubes, e.g. for making multi-wall tubes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
    • B21C37/00—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
    • B21C37/06—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape of tubes or metal hoses; Combined procedures for making tubes, e.g. for making multi-wall tubes
    • B21C37/08—Making tubes with welded or soldered seams
    • 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B17/00—Tube-rolling by rollers of which the axes are arranged essentially perpendicular to the axis of the work, e.g. "axial" tube-rolling
    • B21B17/14—Tube-rolling by rollers of which the axes are arranged essentially perpendicular to the axis of the work, e.g. "axial" tube-rolling without mandrel, e.g. stretch-reducing mills
    • 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

Definitions

  • the present invention relates to a steel pipe excellent in workability and a method for manufacturing the same.
  • the present invention provides a steel pipe excellent in workability, particularly in bending workability, having a pipe axis r value as high as that of a part melted or transformed by seam welding, and a method of manufacturing the same.
  • the purpose is to: Disclosure of the invention
  • the present inventors have considered that in order to solve the above-mentioned problems, it is necessary to process and heat-treat the ERW steel pipe in order to improve the r-value of the welded portion near the seam.
  • the ERW steel pipe was rolled at a temperature range of 600 ° C. or higher and Ac 3 or lower at a diameter reduction ratio of 30% or more (hereinafter referred to as “method according to the present invention”). It was discovered that the r value in the longitudinal direction (in the direction of the pipe axis) was significantly improved to 1.2 or more at all positions in the circumferential direction including the seam portion, and further to 1.6 or more.
  • the reason why a high r-value is not obtained even when diameter reduction rolling is performed at a low temperature is because the work hardening is large and ideal crystal rotation does not occur, or sufficient recovery and recrystallization are performed at a low temperature. This is because it does not occur.
  • the reason why high r value cannot be obtained by recrystallization annealing after cold rolling and diameter reduction is that texture develops in cold rolling and recrystallization due to the effect of the second phase and solute carbon. This is because they do not.
  • the method for producing a high r-value steel sheet is characterized in that a steel to which the amounts of C and N are reduced and to which stabilizer elements such as Ti and Nb are added is rolled at a low temperature and then recrystallized.
  • This cold rolling is different from the hot rolling of the method according to the invention.
  • the ferrite zone plate rolling is performed at 600 ° C. or higher, the r-value is not only improved but rather significantly reduced. This is because, in sheet rolling in which the reduction is performed in the thickness direction, the strain direction is different from that in diameter reduction rolling of the steel pipe in which the reduction is performed in the circumferential direction, so that a texture advantageous for the r value does not develop.
  • a high workability steel pipe having a longitudinal r value of 1.2 or more, more preferably 1.6 or more, in the entire circumferential direction including the seam portion.
  • a steel pipe formed by electric resistance welding of a steel strip is shrunk in a temperature range of 600 or more and Ac 3 or less.
  • the steel pipe formed by ERW welding of the steel strip is reduced in diameter in the temperature range of 600 ° C or higher and Ac 3 or lower.
  • a method for producing a high workability steel pipe characterized in that a diameter reduction of 30% or more is performed.
  • the reduced diameter rolled steel pipe is subjected to a heat treatment during cooling after the rolling or after the completion of the cooling, and reheating, and holding at 600 ° C or more and 900 ° C or less for 1 second or more.
  • Fig. 1 is a graph showing the relationship between the r value in the longitudinal direction and the diameter reduction ratio of the diameter-reduced rolled steel pipe.
  • Fig. 2 is a graph showing the relationship between the r value in the longitudinal direction of the diameter-reduced rolled steel pipe and the temperature on the rolling exit side.
  • Figure 3 is a graph showing the relationship between the thickness deviation of the seam of the reduced-diameter rolled steel pipe and the heating temperature before reduction rolling.
  • the high workability steel pipe according to the present invention has a longitudinal r value of 1.2 or more in the entire circumferential direction including the seam portion.
  • the reason for this is that when the r-value is 1.2 or more, the bendability of the steel pipe is significantly improved. Since the bending property is further improved when the r value is 1.6 or more, a highly workable steel pipe having an r value of 1.6 or more is more preferable.
  • the above-mentioned high workability steel pipe shall be manufactured by subjecting a steel pipe with seam welded by ERW to rolling with a diameter reduction ratio of 30% or more in a temperature range of 600 ° C or more and Ac 3 or less. Can be.
  • the r value is affected by the reduction ratio and temperature of the reduction rolling.
  • Figure 1 shows an ERW steel pipe manufactured from a steel strip having the same composition as steel A in Table 1 by a conventional method, under the condition of an outlet temperature of 730 ° C, with reduced diameter reduction and rolling.
  • Circumferential position of 4 is a graph showing the relationship between the r value in the longitudinal direction and the diameter reduction rate at 0 °, 90 °, 180 °, and 270 °. The seam position was set to 0 ° (the same applies hereinafter). From Fig. 1, it can be seen that an r value of 1.3 or more is obtained at a diameter reduction ratio of 30% or more, regardless of the circumferential position, and an r value of 1.6 or more is obtained at a diameter reduction ratio of 50% or more. .
  • Figure 2 shows that ERW pipes manufactured from strip steel having the same composition as steel A in Table 1 by the usual method were subjected to diameter-reduction rolling under various conditions of the exit temperature and the diameter reduction rate of 30%.
  • 4 is a graph showing the relationship between the r value in the longitudinal direction and the outlet temperature at circumferential positions 0 °, 90 °, 180 °, and 270 ° of the manufactured steel pipe.
  • Fig. 2 shows that an r value of 1.2 or more can be obtained at an outlet temperature of 600 ° C or more.
  • the lower limit of the diameter reduction rolling temperature was set to 600 ° C, and the lower limit of the diameter reduction rate was set to 30%.
  • the upper limit of the diameter reduction rolling temperature is the upper limit of the temperature range in which the steel structure contains ferrite, and the Ac 3 temperature.
  • the r-value does not improve even if diameter reduction rolling is performed on steel with a structure that does not contain ferrite.
  • the AC 3 temperature is determined by the chemical composition of the steel pipe, and can be determined by experiment. Its range is generally below 900 ° C.
  • the second phase phase other than ferrite
  • austenite may be in the second phase.
  • diameter reduction rolling is performed at a temperature at which ferrite becomes a main phase (a phase having a volume ratio of 50% or more).
  • the gist of the present invention is to reduce the diameter of a steel pipe in a temperature range that is a ferrite phase.
  • the heating temperature before the diameter reduction rolling may be any of a temperature at which a single phase of austenite, a temperature of two phases of austenite and ferrite, a temperature of a single phase of ferrite, and the like.
  • rolling may be performed at a temperature at which the austenite single phase or the main phase is formed.
  • FIG. 3 shows that ERW pipes manufactured from a steel strip having the same composition as steel A in Table 1 by the usual method were subjected to various heating temperatures and reduced under the conditions of a diameter reduction rate of 30% and a rolling temperature of 700. It is a graph which shows the relationship between the heating temperature of the steel pipe manufactured by diameter rolling, and a wall thickness deviation rate. From FIG. 3, it can be seen that heating before diameter reduction rolling is preferably equal to or higher than the Ac i temperature in order to suppress uneven thickness and wrinkling near the seam.
  • the Ac i temperature is a temperature determined by the chemical composition of the steel pipe, and may be determined experimentally. Its temperature is above about 800 ° C. However, if the heating temperature is too high, there is a problem that the crystal grain size becomes too large and the surface is roughened during processing.
  • Cooling after heating does not need to be particularly limited. After the heating, for example, the steel may be cooled to a temperature at which the ferrite becomes a main phase and subjected to diameter reduction rolling, or may be cooled to room temperature, reheated and then subjected to diameter reduction rolling.
  • the steel pipe after the diameter-reduction rolling is subjected to a heat treatment for holding the steel pipe at a temperature of 600 ° C. to 900 ° C. for 1 second or more.
  • the heat treatment is preferably performed under the conditions of a holding temperature of 600 ° C. or more and 900 or less and a holding time of 1 second or more.
  • the heat treatment may be performed during cooling after the diameter reduction rolling, or may be performed by reheating the steel pipe after the completion of the cooling.
  • a hot-rolled steel sheet having the chemical composition shown in Table 1 was formed into an ERW steel pipe by a normal method, and was subjected to diameter reduction rolling under the conditions shown in Table 2. Heating before diameter reduction rolling reaches the temperature shown in Table 2, Performed without holding or for 1-600 seconds. The circumferential position of the obtained steel pipe is 0 °, 90 °, 180 °.
  • the JIS 12 No. A tensile test specimen was sampled from 270 °, subjected to a tensile test nominal strain 6% to 7% Paste strain gauges gauge length 2 mm, width direction to the true strain £ L in the longitudinal Direction The true distortion E w of the sample was measured, and the r value was calculated from the slope P.
  • Table 3 shows the results together with the tensile strength (TS) and elongation (E1).
  • the r value reached 1.2 or more at any circumferential position, whereas in the comparative example, the r value was less than 1.2. Further, those having a heating temperature of Ac 1 or higher have a small wall thickness unevenness and do not have wrinkles. Industrial applicability
  • region including the seam part of a steel pipe is high, and the high workability steel pipe with favorable shape can be provided. Bending of steel pipes ⁇ The limits of pipe expansion are greatly improved, and the process can be omitted and the weight can be reduced by integral molding. Furthermore, it was difficult to increase the r-value by the conventional manufacturing method of simply welding electric steel sheets to high-strength steels such as hot-rolled steel sheets and dual-phase steels, as well as low-carbon steel, medium-carbon steel, and high-carbon steel. High r-values can be obtained even with ERW steel pipes used as the material. Expanding the scope of bending of steel pipes is important for industrial development.

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

Abstract

L'invention concerne un tuyau en acier à haute formabilité, dont la valeur r dans le sens longitudinal est supérieure ou égale à 1,2 et de préférence supérieure ou égale à 1,6 sur toute la partie comportant une zone de raccord. L'invention concerne également un procédé de fabrication correspondant, qui consiste à chauffer un tuyau de cercles d'acier assemblés par soudure électrique, à une température Ac1 ou supérieure, et à soumettre le tuyau échauffé à une opération d'étirage-réduction, selon une réduction de diamètre supérieure ou égale à 30 %, à 600° C ou plus et jusqu'à une température Ac1, puis éventuellement à chauffer de nouveau le tuyau durant ou après le refroidissement qui suit l'opération susmentionnée, à une température comprise entre 600° C et 900° C, en maintenant la température pendant une seconde au moins. Ce type de tuyau à haute formabilité présente une partie fondue ou transformée en soudure par joints, avec une valeur r élevée dans le sens axial, équivalant à la valeur r d'une partie non soumise à la soudure, et la formabilité est particulièrement remarquable à la courbure.
PCT/JP2001/005053 2000-01-28 2001-06-14 Tuyau en acier a haute formabilite, et procede de fabrication WO2002103069A1 (fr)

Priority Applications (7)

Application Number Priority Date Filing Date Title
JP2000019557A JP3794230B2 (ja) 2000-01-28 2000-01-28 高加工性鋼管の製造方法
EP01938656A EP1437422A4 (fr) 2001-06-14 2001-06-14 Tuyau en acier a haute formabilite, et procede de fabrication
BRPI0110441-1B1A BR0110441B1 (pt) 2001-06-14 2001-06-14 mÉtodo de produÇço de uma tubulaÇço de aÇo de alta possibilidade de trabalho.
PCT/JP2001/005053 WO2002103069A1 (fr) 2000-01-28 2001-06-14 Tuyau en acier a haute formabilite, et procede de fabrication
US10/258,982 US7591914B2 (en) 2000-01-28 2001-06-14 High-workability steel pipe and method of producing same
CNB018086209A CN1234896C (zh) 2001-06-14 2001-06-14 高加工性钢管及其制造方法
CA002403830A CA2403830C (fr) 2001-06-14 2001-06-14 Tuyau en acier a ouvrabilite elevee et methode de production

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2000019557A JP3794230B2 (ja) 2000-01-28 2000-01-28 高加工性鋼管の製造方法
PCT/JP2001/005053 WO2002103069A1 (fr) 2000-01-28 2001-06-14 Tuyau en acier a haute formabilite, et procede de fabrication

Publications (1)

Publication Number Publication Date
WO2002103069A1 true WO2002103069A1 (fr) 2002-12-27

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ID=11737433

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2001/005053 WO2002103069A1 (fr) 2000-01-28 2001-06-14 Tuyau en acier a haute formabilite, et procede de fabrication

Country Status (5)

Country Link
EP (1) EP1437422A4 (fr)
CN (1) CN1234896C (fr)
BR (1) BR0110441B1 (fr)
CA (1) CA2403830C (fr)
WO (1) WO2002103069A1 (fr)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006057098A1 (fr) * 2004-11-26 2006-06-01 Jfe Steel Corporation Tuyau en acier ayant d’excellentes proprietes electromagnetiques et procede pour sa fabrication
KR20150023726A (ko) * 2012-06-28 2015-03-05 제이에프이 스틸 가부시키가이샤 냉간 가공성, 피삭성 및 퀀칭성이 우수한 고탄소 강관 및 그 제조 방법
US10738366B2 (en) 2013-12-20 2020-08-11 Nippon Steel Corporation Electric-resistance welded steel pipe
CN109689238B (zh) * 2016-07-14 2022-05-27 塔塔钢铁荷兰钢管有限责任公司 钢管的在线制造方法

Citations (9)

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Publication number Priority date Publication date Assignee Title
JPH0641689A (ja) * 1992-06-22 1994-02-15 Nippon Steel Corp 加工性の優れた高Ｃｒ含有鋼管
JPH1058161A (ja) * 1996-06-10 1998-03-03 Kawasaki Steel Corp 溶接鋼管およびその製造方法
JPH10175027A (ja) * 1996-12-17 1998-06-30 Nippon Steel Corp ハイドロフォーム加工用金属管
EP0924312A1 (fr) * 1997-06-26 1999-06-23 Kawasaki Steel Corporation Tuyau en acier a grains ultrafins et procede de fabrication dudit tuyau
JP2000096143A (ja) * 1998-09-22 2000-04-04 Kawasaki Steel Corp 鋼管の製造方法
JP2000096142A (ja) * 1998-09-21 2000-04-04 Kawasaki Steel Corp 鋼管の絞り圧延方法
JP2000212694A (ja) * 1999-01-20 2000-08-02 Nippon Steel Corp 加工性に優れた電縫鋼管とその製造方法
JP2001162305A (ja) * 1999-12-08 2001-06-19 Kawasaki Steel Corp 鋼管の製造方法
JP2001214218A (ja) * 2000-01-28 2001-08-07 Kawasaki Steel Corp 高加工性鋼管およびその製造方法

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DE2900022C3 (de) * 1979-01-02 1981-12-03 Estel Hoesch Werke Ag, 4600 Dortmund Verfahren zum Herstellen von Profilen
JPH04143015A (ja) * 1990-10-05 1992-05-18 Sumitomo Metal Ind Ltd 溶接部靭性の優れた高張力電縫鋼管の製造法
DE4318931C1 (de) * 1993-06-03 1994-12-01 Mannesmann Ag Verfahren zur Herstellung von geschweißten Rohren
JP4571754B2 (ja) * 2001-03-13 2010-10-27 新日本製鐵株式会社 成形性に優れた鋼管の製造法

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Publication number Priority date Publication date Assignee Title
JPH0641689A (ja) * 1992-06-22 1994-02-15 Nippon Steel Corp 加工性の優れた高Ｃｒ含有鋼管
JPH1058161A (ja) * 1996-06-10 1998-03-03 Kawasaki Steel Corp 溶接鋼管およびその製造方法
JPH10175027A (ja) * 1996-12-17 1998-06-30 Nippon Steel Corp ハイドロフォーム加工用金属管
EP0924312A1 (fr) * 1997-06-26 1999-06-23 Kawasaki Steel Corporation Tuyau en acier a grains ultrafins et procede de fabrication dudit tuyau
JP2000096142A (ja) * 1998-09-21 2000-04-04 Kawasaki Steel Corp 鋼管の絞り圧延方法
JP2000096143A (ja) * 1998-09-22 2000-04-04 Kawasaki Steel Corp 鋼管の製造方法
JP2000212694A (ja) * 1999-01-20 2000-08-02 Nippon Steel Corp 加工性に優れた電縫鋼管とその製造方法
JP2001162305A (ja) * 1999-12-08 2001-06-19 Kawasaki Steel Corp 鋼管の製造方法
JP2001214218A (ja) * 2000-01-28 2001-08-07 Kawasaki Steel Corp 高加工性鋼管およびその製造方法

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Title
KAWABATA ET AL.: "Shukukei atsuen ni yoru koukan shuugou soshiki no keisei kikou", ZAIRYOU TO PROCESS, vol. 14, no. 2, 1 March 2001 (2001-03-01), pages 438, XP002945949 *
See also references of EP1437422A4 *

Also Published As

Publication number Publication date
BR0110441B1 (pt) 2013-06-18
EP1437422A4 (fr) 2006-08-23
EP1437422A1 (fr) 2004-07-14
CA2403830C (fr) 2009-06-30
CN1426489A (zh) 2003-06-25
CA2403830A1 (fr) 2002-12-14
CN1234896C (zh) 2006-01-04
BR0110441A (pt) 2003-07-01

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