Global Patent Index - EP 1546417 B1

EP 1546417 B1 20120425 - HIGH STRENGTH SEAMLESS STEEL PIPE EXCELLENT IN HYDROGEN-INDUCED CRACKING RESISTANCE AND ITS PRODUCTION METHOD

Title (en)

HIGH STRENGTH SEAMLESS STEEL PIPE EXCELLENT IN HYDROGEN-INDUCED CRACKING RESISTANCE AND ITS PRODUCTION METHOD

Title (de)

HOCHFESTES NAHTLOSES STAHLROHR MIT HERVORRAGENDER BESTÄNDIGKEIT GEGEN DER WASSERSTOFFINDUZIERTER RISSBILDUNG UND HERSTELLUNGSVERFAHREN DAFÜR

Title (fr)

TUYAU EN ACIER SANS SOUDURE A HAUTE RESISTANCE, S'AGISSANT NOTAMMENT DE RESISTANCE AUX CRAQUELURES PROVOQUEES PAR L'HYDROGENE ET PROCEDE DE FABRICATION

Publication

EP 1546417 B1 20120425 (EN)

Application

EP 03799144 A 20030926

Priority

  • JP 0312373 W 20030926
  • JP 2002288661 A 20021001
  • JP 2003051427 A 20030227

Abstract (en)

[origin: WO2004031420A1] The present invention relates to a high strength seamless steel pipe excellent in hydrogen-induced cracking resistance, characterized by consisting of, by mass %, C: 0.03 - 0.11 %, Si: 0.05 - 0.5 %, Mn: 0.8 - 1.6 %, P: 0.025 % or less, S: 0.003 % or less, Ti: 0.002 - 0.017 %, Al: 0.001 - 0.10 %, Cr: 0.05 - 0.5 %, Mo: 0.02 - 0.3 %, V: 0.02 - 0.20 %, Ca: 0.0005 - 0.005 %, N: 0.008 % or less and O (Oxygen): 0.004 % or less, and the balance Fe and impurities, and also characterized in that the microstructure of the steel is bainite and/or martensite, ferrite is precipitated at grain boundaries and yield stress is 483 MPa or more. Further, to ensure high strength of the steel, the seamless steel pipe preferably contains, by mass %, at least one of Cu: 0.05 - 0.5 % and Ni: 0.05 - 0.5 %. To produce the above-mentioned steel pipe, it is desirable to limit a starting temperature of quenching after rolling, a cooling rate and a tempering temperature. By this configuration a seamless steel pipe having an yield stress of 483 MPa or more and excellent HIC resistance, which is suitable for a pipeline, can be provided.

IPC 8 full level

B21B 3/00 (2006.01); C21D 8/10 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/20 (2006.01); C22C 38/22 (2006.01); C22C 38/24 (2006.01); C22C 38/28 (2006.01); C22C 38/38 (2006.01); C22C 38/42 (2006.01); C22C 38/44 (2006.01); C22C 38/46 (2006.01); C22C 38/50 (2006.01); C22C 38/58 (2006.01)

CPC (source: EP)

C21D 8/10 (2013.01); C21D 8/105 (2013.01); C22C 38/002 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C22C 38/20 (2013.01); C22C 38/22 (2013.01); C22C 38/24 (2013.01); C22C 38/42 (2013.01); C22C 38/44 (2013.01); C22C 38/46 (2013.01); C21D 2211/002 (2013.01); C21D 2211/005 (2013.01); C21D 2211/008 (2013.01)

Designated contracting state (EPC)

AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PT RO SE SI SK TR

DOCDB simple family (publication)

WO 2004031420 A1 20040415; AR 041434 A1 20050518; AT E555220 T1 20120515; AU 2003264947 A1 20040423; AU 2003264947 B2 20060831; BR 0314819 A 20050802; BR 0314819 B1 20110712; CA 2500518 A1 20040415; CA 2500518 C 20100803; EP 1546417 A1 20050629; EP 1546417 B1 20120425; JP 2004176172 A 20040624; MX PA05003412 A 20051005; NO 20051405 L 20050621; NO 339589 B1 20170109

DOCDB simple family (application)

JP 0312373 W 20030926; AR P030103550 A 20030929; AT 03799144 T 20030926; AU 2003264947 A 20030926; BR 0314819 A 20030926; CA 2500518 A 20030926; EP 03799144 A 20030926; JP 2003051427 A 20030227; MX PA05003412 A 20030926; NO 20051405 A 20050317