EP0356417A1 - Procédé pour la fabrication de pièces tubulaires résistant à la corrosion sous tension, notamment de masses-tiges non magnétisables en acier austénitique et pièces ainsi obtenues - Google Patents

Procédé pour la fabrication de pièces tubulaires résistant à la corrosion sous tension, notamment de masses-tiges non magnétisables en acier austénitique et pièces ainsi obtenues Download PDF

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Publication number
EP0356417A1
EP0356417A1 EP89890199A EP89890199A EP0356417A1 EP 0356417 A1 EP0356417 A1 EP 0356417A1 EP 89890199 A EP89890199 A EP 89890199A EP 89890199 A EP89890199 A EP 89890199A EP 0356417 A1 EP0356417 A1 EP 0356417A1
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EP
European Patent Office
Prior art keywords
temperature
cooled
tubular body
wall
stresses
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
EP89890199A
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German (de)
English (en)
Other versions
EP0356417B1 (fr
Inventor
Helmut Dr.Mont.Dipl.-Ing. Pohl
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.)
Schoeller Bleckmann GmbH
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Schoeller Bleckmann GmbH
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Publication date
Application filed by Schoeller Bleckmann GmbH filed Critical Schoeller Bleckmann GmbH
Publication of EP0356417A1 publication Critical patent/EP0356417A1/fr
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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
    • 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
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/004—Heat treatment of ferrous alloys containing Cr and Ni
    • 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

Definitions

  • precipitation hardened alloys with contents of approx. 33% Ni, 18% Cr, 2% Ti, 0.5% Al and 0.004% N should bring about significant improvements in the performance characteristics of drill collars or drill string parts.
  • Another disadvantage is that high local strain hardening of the material, which is formed in the near-surface zone when mechanical pressure is applied, increases the tendency of the material to pitting. In the event of pitting, the compressive stress layer is undermined and stress corrosion cracking of the part increases.
  • the mechanical application of residual compressive stresses in the surface layer of parts also has the disadvantage that only simple shapes or contours can be treated accordingly last operation must be done without subsequent calibration. It is therefore practically not possible to create residual compressive stresses in the near-surface zone on edges, threaded parts, in corners, holes and back-turns as well as on chamfers and discontinuous surface parts in order to prevent stress corrosion cracking.
  • the invention was based on the objects of avoiding the above disadvantages and of creating a method for producing tubular bodies which are resistant to stress corrosion cracking, in particular non-magnetizable drill rods and rod parts made of austenitic steels.
  • a further object of the invention relates to tubular bodies which are resistant to stress corrosion cracking and are produced by this method, in particular non-magnetizable drill rods and rod parts made of austenitic steel.
  • the body after solution annealing, quenching and after deformation at a temperature of below 500 ° C to increase the material strength and after machining or drilling a hole to a temperature of 220 to 600 ° C, at least up to a temperature equalization with a temperature difference of at most 10 ° C in the body wall, at most a time t in minutes at a temperature T in ° C according to the context is kept, from this temperature or this starting temperature is cooled by increased removal of thermal energy at least from the inner surface of the tubular body and the cooled surface has a temperature drop of at least 100 ° C / min from the starting temperature to half the value between the starting temperature and room temperature.
  • Tubular bodies produced in accordance with this process in particular non-magnetizable drill rods and rod parts made of austenitic steel, according to the invention have local tensile residual stresses of less than 100 N / mm2 in the zones near the surface to a depth of at least 8 mm. It is particularly preferred if the near-surface zones have residual compressive stresses to a depth of at least 4 mm, preferably at least 8 mm, and that the tensile residual stresses that may occur in the entire cross-section of the wall are less than 150 N / mm2, i.e. below the triggering voltage for stress corrosion cracking , preferably less than 120 N / mm2.
  • tubular bodies, especially collars Due to a deformation of the blank at temperatures below 500 ° C, which serves to work harden or increase the yield strength of the material, tubular bodies, especially collars, show considerable differences in the local internal stresses in the wall, etc. compressive stresses on the outer surface and high tensile stresses on the surface of the hollow, i.e. the bore, which are well above the limit for triggering stress corrosion cracking. It has surprisingly been found that in a tubular body consisting of solution-annealed, quenched and cold-formed austenitic material, heating to appropriate temperatures while adhering to certain conditions with subsequent intensified cooling can cause stress states.
  • the temperature difference in the pipe wall after heating to the initial temperature should be kept below 10 ° C. Longer holding times at the initial temperature have an unfavorable effect because this causes the solution-annealed, quenched and work-hardened steels, for example austenitic Mn-Cr steel, to be sensitized to inter-crystalline crack corrosion.
  • tubular body is cooled from the starting temperature by increasing heat removal at least from the inner wall, because in the area of the inner surface of the wall the highest tensile stresses originating from cold working or work hardening have to be redistributed. Due to low cooling intensities, no sufficient residual stress redistribution is effected, so that the cooled surface of the tube wall must experience a temperature drop from the starting temperature to half the value between the starting temperature and room temperature of at least 100 ° C./min.
  • the method according to the invention brings about a residual stress redistribution and can be used for the production of tubular bodies which are resistant to stress corrosion cracking, in particular non-magnetizable drill rods and rod parts made of austenistic steels.
  • the prejudices of the professional world had to be overcome, e.g. that heating to higher initial temperatures leads to an unacceptable softening or lowering of the yield point of the cold-formed material, and that low initial temperatures can have no effect, because during the subsequent cooling process, only elastic material deformations occur arise.
  • the increased strength and the high tensile stresses on the inner surface of the tube cause cracks, in particular longitudinal cracks, even when heated to the initial temperature.
  • the corrosion specialist feared that renewed heating of a material quenched from solution temperature and work hardened would cause sensitization, which would make the material in chloride-containing media susceptible to grain breakdown or intergranular crack propagation.
  • Fig. 1 shows schematically stress states in the wall of a tubular body.
  • the stress redistribution by intensively cooling the tube wall from temperatures of, for example, 300 ° C. and 400 ° C. has the effect that the internal stresses in the entire tube wall are below 150 N / mm2, namely the triggering voltage of the stress corrosion cracking, and the body is therefore completely resistant to stress corrosion cracking. Compressive stresses down to a depth of more than 4 mm are achieved on the inner surface.
  • Intensified cooling from an initial temperature of 550 ° C increases the internal compressive stresses and their effective range on the inner surface of the pipe wall (curve 6), which can be used for a recalibration by machining.
  • Curve 2 shows the stress curve in a pipe wall, which can be set by a method according to AT-PS 364 592 or according to the prior art, high internal compressive stresses prevailing on the inner surface, but these compressive stresses at a small distance from the surface in pass high tensile stresses.
  • the invention is illustrated further below by a practical example: A block weighing approx.
  • the residual stresses on the AD were 0 ⁇ -157 N / mm2 (residual compressive stress) and on the ID +390 N / mm2 (residual tensile stress), the measured values representing the arithmetic mean of 3 measurements using the ring-core method.
  • the tubular semi-finished product or rod (approx. 700 mm minimum length for the above sample) was heated in an electric furnace at 415 ° C, with a temperature difference in the tube wall at the end of the heating period of 0.8 ° C.
  • jet cooling was initially carried out on the inside surface with a quantity of 1500 - 2500 l / min and after 10 to 30 s, preferably 20 s, also on the outside surface with a cooling water quantity of approx. 100 l / min and meter length with a temperature drop of the surface of approx. 350 ° C, at least to a temperature below 100 ° C.
  • a drill string part was made from the semi-finished product and further samples were taken from it at the machined points. It was shown in the SCC test that cut-outs made in the pipe wall by milling, turning and planing as well as the NC-cut threads do not cause any cracks, which results from the non-critical residual stress condition in the entire volume of the part.
  • the method according to the invention is particularly advantageous for austenitic steels with a directional analysis C: max. 0.2% by weight; Mn: 0-25% by weight; Cr: 12-30% by weight; Mo: 0-5% by weight; Ni: 0-75% by weight; N: 0-1% by weight; Ti: 0-3% by weight; Nb: 0-3% by weight; Cu: 0-3% by weight, rest of iron applicable.
  • Mn-Cr austenites with 17-20% by weight Mn and 12-14% by weight Cr and Cr-Ni austenites with 17-24% by weight Cr and 10-20% by weight are particularly preferred.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Heat Treatment Of Articles (AREA)
  • Earth Drilling (AREA)
  • Heat Treatments In General, Especially Conveying And Cooling (AREA)
  • Physical Vapour Deposition (AREA)
  • Coating With Molten Metal (AREA)
  • Extrusion Moulding Of Plastics Or The Like (AREA)
  • Shaping Of Tube Ends By Bending Or Straightening (AREA)
  • Heat Treatment Of Steel (AREA)
  • Treatments Of Macromolecular Shaped Articles (AREA)
  • Prevention Of Electric Corrosion (AREA)
  • Electrolytic Production Of Non-Metals, Compounds, Apparatuses Therefor (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
EP89890199A 1988-08-04 1989-07-27 Procédé pour la fabrication de pièces tubulaires résistant à la corrosion sous tension, notamment de masses-tiges non magnétisables en acier austénitique et pièces ainsi obtenues Expired - Lifetime EP0356417B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AT1965/88A AT392802B (de) 1988-08-04 1988-08-04 Verfahren zur herstellung von spannungsrisskorrosionsbestaendigen rohrfoermigen koerpern, insbesondere nichtmagnetisierbaren schwerstangen aus austenitischen staehlen
AT1965/88 1988-08-04

Publications (2)

Publication Number Publication Date
EP0356417A1 true EP0356417A1 (fr) 1990-02-28
EP0356417B1 EP0356417B1 (fr) 1993-05-26

Family

ID=3524888

Family Applications (1)

Application Number Title Priority Date Filing Date
EP89890199A Expired - Lifetime EP0356417B1 (fr) 1988-08-04 1989-07-27 Procédé pour la fabrication de pièces tubulaires résistant à la corrosion sous tension, notamment de masses-tiges non magnétisables en acier austénitique et pièces ainsi obtenues

Country Status (10)

Country Link
US (1) US5026436A (fr)
EP (1) EP0356417B1 (fr)
JP (1) JPH0270884A (fr)
KR (1) KR900003387A (fr)
AT (2) AT392802B (fr)
BR (1) BR8903914A (fr)
CA (1) CA1334572C (fr)
DE (1) DE58904473D1 (fr)
MX (1) MX173658B (fr)
NO (1) NO174163C (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999019522A1 (fr) * 1997-10-08 1999-04-22 Mannesmann Ag Procede pour eviter des tapures de trempe a la surface interieure d'un corps creux cylindrique
CN110317941A (zh) * 2019-08-13 2019-10-11 上海亦又新能源科技有限公司 一种地质钻杆公接头增强螺纹根部加工方法及其应用
DE102019123174A1 (de) * 2019-08-29 2021-03-04 Mannesmann Stainless Tubes GmbH Austenitische Stahllegierung mit verbesserter Korrosionsbeständigkeit bei Hochtemperaturbeanspruchung

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3186678B2 (ja) * 1997-12-10 2001-07-11 日産自動車株式会社 ベルト式無段変速機用金属帯の製造方法
US6406570B1 (en) * 1998-03-26 2002-06-18 Mettler-Toledo, Gmbh Elastic component for a precision instrument and process for its manufacture
DE19813459A1 (de) * 1998-03-26 1999-09-30 Mettler Toledo Gmbh Elastisch verformbares Bauteil und Verfahren zu seiner Herstellung
US6012744A (en) * 1998-05-01 2000-01-11 Grant Prideco, Inc. Heavy weight drill pipe
KR100472931B1 (ko) * 2002-08-09 2005-03-10 정동택 세라믹구 제조방법
JP4759302B2 (ja) * 2004-04-06 2011-08-31 日立Ｇｅニュークリア・エナジー株式会社 熱処理方法及びその装置
GB201304771D0 (en) * 2013-03-15 2013-05-01 Petrowell Ltd Heat treat production fixture
JP7385174B2 (ja) * 2019-12-11 2023-11-22 Tdk株式会社 磁性シート、および、磁性シートを備えるコイルモジュール、並びに非接触給電装置。

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE671131C (de) * 1932-08-26 1939-02-01 Kohle Und Eisenforschung G M B Verfahren zur Erzeugung von elastischen Vorspannungen in Gegenstaenden aus Stahl
DE3004872A1 (de) * 1979-03-15 1980-09-18 Usui Kokusai Sangyo Kk Rohr fuer hochdruckfluessigkeit und verfahren zu dessen herstellung
EP0035091A1 (fr) * 1980-01-25 1981-09-09 SCHOELLER-BLECKMANN Gesellschaft m.b.H. Procédé et appareil pour la fabrication de barres lourdes en acier austénitique, non magnétisables et résistant à la corrosion fissurante sous tension
EP0205828A1 (fr) * 1985-06-10 1986-12-30 Hoesch Aktiengesellschaft Procédé et utilisation d'un acier pour la fabrication de tubes en acier à haute résistance aux gaz acides

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2115834B (en) * 1982-03-02 1985-11-20 British Steel Corp Non-magnetic austenitic alloy steels
JPS58167724A (ja) * 1982-03-26 1983-10-04 Kobe Steel Ltd 石油掘削スタビライザ−用素材の製造方法
US4502886A (en) * 1983-01-06 1985-03-05 Armco Inc. Austenitic stainless steel and drill collar
AT381658B (de) * 1985-06-25 1986-11-10 Ver Edelstahlwerke Ag Verfahren zur herstellung von amagnetischen bohrstrangteilen

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE671131C (de) * 1932-08-26 1939-02-01 Kohle Und Eisenforschung G M B Verfahren zur Erzeugung von elastischen Vorspannungen in Gegenstaenden aus Stahl
DE3004872A1 (de) * 1979-03-15 1980-09-18 Usui Kokusai Sangyo Kk Rohr fuer hochdruckfluessigkeit und verfahren zu dessen herstellung
EP0035091A1 (fr) * 1980-01-25 1981-09-09 SCHOELLER-BLECKMANN Gesellschaft m.b.H. Procédé et appareil pour la fabrication de barres lourdes en acier austénitique, non magnétisables et résistant à la corrosion fissurante sous tension
EP0205828A1 (fr) * 1985-06-10 1986-12-30 Hoesch Aktiengesellschaft Procédé et utilisation d'un acier pour la fabrication de tubes en acier à haute résistance aux gaz acides

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN, Band 3, Nr. 114 (C-59), 21. September 1979, Seite 93 C 59; & JP-A-54 94 415 (HITACHI SEISAKUSHO K.K.) 26-07-1979 *
PATENT ABSTRACTS OF JAPAN, Band 8, Nr. 41 (C-211)[1478], 22. Februar 1984; & JP-A-58 199 814 (SHIN NIPPON SEITETSU K.K.) 21-11-1983 *
PATENT ABSTRACTS OF JAPAN, Band 9, Nr. 254 (C-308)[1977], 11. Oktober 1985; & JP-A-60 106 916 (ISHIKAWAJIMA HARIMA JUKOGYO K.K.) 12-06-1985 *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999019522A1 (fr) * 1997-10-08 1999-04-22 Mannesmann Ag Procede pour eviter des tapures de trempe a la surface interieure d'un corps creux cylindrique
CN110317941A (zh) * 2019-08-13 2019-10-11 上海亦又新能源科技有限公司 一种地质钻杆公接头增强螺纹根部加工方法及其应用
CN110317941B (zh) * 2019-08-13 2020-12-15 上海亦又新能源科技有限公司 一种地质钻杆公接头增强螺纹根部加工方法及其应用
DE102019123174A1 (de) * 2019-08-29 2021-03-04 Mannesmann Stainless Tubes GmbH Austenitische Stahllegierung mit verbesserter Korrosionsbeständigkeit bei Hochtemperaturbeanspruchung

Also Published As

Publication number Publication date
US5026436A (en) 1991-06-25
CA1334572C (fr) 1995-02-28
ATE89870T1 (de) 1993-06-15
DE58904473D1 (de) 1993-07-01
EP0356417B1 (fr) 1993-05-26
NO174163B (no) 1993-12-13
JPH0270884A (ja) 1990-03-09
BR8903914A (pt) 1990-03-27
AT392802B (de) 1991-06-25
NO174163C (no) 1994-03-23
MX173658B (es) 1994-03-22
ATA196588A (de) 1990-11-15
KR900003387A (ko) 1990-03-26
NO893152L (no) 1990-02-05
NO893152D0 (no) 1989-08-03

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