Global Patent Index - EP 4043591 A4

EP 4043591 A4 20221012 - HIGH-STRENGTH STAINLESS STEEL SEAMLESS PIPE FOR OIL WELLS

Title (en)

HIGH-STRENGTH STAINLESS STEEL SEAMLESS PIPE FOR OIL WELLS

Title (de)

NAHTLOSES ROHR AUS HOCHFESTEM ROSTFREIEM STAHL FÜR ÖLBOHRLÖCHER

Title (fr)

TUYAU SANS SOUDURE EN ACIER INOXYDABLE À HAUTE RÉSISTANCE POUR PUITS DE PÉTROLE

Publication

EP 4043591 A4 20221012 (EN)

Application

EP 20904807 A 20201120

Priority

  • JP 2019232430 A 20191224
  • JP 2020043310 W 20201120

Abstract (en)

[origin: EP4043591A1] To provide a high-strength seamless stainless steel pipe for oil well that has high strength, is excellent in hot workability, has excellent carbon dioxide gas corrosion resistance, and is excellent in SSC resistance under a low temperature environment. A high-strength seamless stainless steel pipe for oil well having a composition containing the particular components, the balance being Fe and unavoidable impurities, and satisfying the following expression (1) and the following expression (2), having a number density of an inclusion having a major axis of 5 µm or more and 0.5 < Ti/(Ti+Al+Mg+Ca) < 1.0 of 0.5 per mm<sup>2</sup> or more and 3 per mm<sup>2</sup> or less, and having a yield strength of 655 MPa or more, wherein in 0.5 < Ti/ (Ti+Al+Mg+Ca) < 1.0, Ti, Al, Mg, and Ca represent the contents (% by mass) of the elements in the inclusion, and an element that is not contained is designated as 0,        Cr+0.65Ni+0.6Mo+0.55Cu-20C ≥ 15.0     (1)        Cr+Mo+0.3Si-43.3C-0.4Mn-Ni-0.3Cu-9N ≤ 11.0     (2)wherein Cr, Ni, Mo, Cu, C, Si, Mn, and N represent the contents (% by mass) of the elements, and an element that is not contained is designated as 0.

IPC 8 full level

C22C 38/44 (2006.01); C21D 1/18 (2006.01); C21D 1/22 (2006.01); C21D 1/25 (2006.01); C21D 6/00 (2006.01); C21D 6/02 (2006.01); C21D 8/10 (2006.01); C21D 9/08 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/06 (2006.01); C22C 38/42 (2006.01); C22C 38/46 (2006.01); C22C 38/48 (2006.01); C22C 38/50 (2006.01); C22C 38/52 (2006.01); C22C 38/54 (2006.01)

CPC (source: EP US)

C21D 1/18 (2013.01 - EP); C21D 1/22 (2013.01 - EP); C21D 1/25 (2013.01 - EP); C21D 6/004 (2013.01 - EP); C21D 6/02 (2013.01 - EP); C21D 8/105 (2013.01 - EP); C21D 9/08 (2013.01 - EP US); C21D 9/085 (2013.01 - EP); C22C 38/001 (2013.01 - EP US); C22C 38/002 (2013.01 - EP US); C22C 38/004 (2013.01 - EP US); C22C 38/005 (2013.01 - EP); C22C 38/008 (2013.01 - EP); C22C 38/02 (2013.01 - EP US); C22C 38/04 (2013.01 - EP US); C22C 38/06 (2013.01 - EP US); C22C 38/42 (2013.01 - EP); C22C 38/44 (2013.01 - EP US); C22C 38/46 (2013.01 - EP US); C22C 38/48 (2013.01 - EP); C22C 38/50 (2013.01 - EP US); C22C 38/52 (2013.01 - EP US); C22C 38/54 (2013.01 - EP); C21D 2211/001 (2013.01 - US); C21D 2211/004 (2013.01 - EP); C21D 2211/008 (2013.01 - EP)

Citation (search report)

Designated contracting state (EPC)

AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

Designated extension state (EPC)

BA ME

DOCDB simple family (publication)

EP 4043591 A1 20220817; EP 4043591 A4 20221012; AR 120872 A1 20220323; BR 112022011761 A2 20220830; CN 114829647 A 20220729; JP 6950851 B1 20211013; JP WO2021131445 A1 20211223; MX 2022007286 A 20220712; US 2023033540 A1 20230202; WO 2021131445 A1 20210701

DOCDB simple family (application)

EP 20904807 A 20201120; AR P200103614 A 20201222; BR 112022011761 A 20201120; CN 202080087895 A 20201120; JP 2020043310 W 20201120; JP 2021510991 A 20201120; MX 2022007286 A 20201120; US 202017785164 A 20201120