×

HIGH STRENGTH BAINITIC STEEL FOR OCTG APPLICATIONS

  • US 20100294401A1
  • Filed: 11/19/2007
  • Published: 11/25/2010
  • Est. Priority Date: 11/19/2007
  • Status: Active Grant
First Claim
Patent Images

1. Process for the production of high strength bainitic steel seamless pipes comprising the following steps:

  • a) providing a steel having a composition comprising 0.2-0.4% by weight of C 0.05-1.5% by weight of Mn;

    1.0-2.0% by weight of Si and 0-0.5% by weight of Al or, alternatively, 1.0-2.0% by weight of Al and 0-0.5% by weight of Si;

    0.5-2.0% by weight of Cr;

    0.2-0.5% by weight of Mo;

    0.5-3.7% by weight of Ni;

    the remainder being iron and inevitable impurities;

    b) hot rolling said steel at a predetermined temperature such as to obtain a seamless steel pipe;

    c) continuously cooling the steel from the rolling temperature naturally in air or by a controlled cooling with an average cooling rate comprised between 0.10 and 1.0°

    C. per second in order to obtain mainly bainitic structures.

View all claims
  • 3 Assignments
Timeline View
Assignment View
    ×
    ×