The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
Nov. 26, 2019

Filed:

Jun. 23, 2016
Applicant:

Nippon Steel & Sumitomo Metal Corporation, Tokyo, JP;

Inventors:

Taro Oe, Takaishi, JP;

Keiichi Kondo, Izumisano, JP;

Hiroki Kamitani, Wakayama, JP;

Yuji Arai, Amagasaki, JP;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C21D 9/08 (2006.01); C22C 38/00 (2006.01); C22C 38/58 (2006.01); C21D 1/18 (2006.01); C21D 6/00 (2006.01); C21D 8/10 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/06 (2006.01); C22C 38/42 (2006.01); C22C 38/44 (2006.01); C22C 38/46 (2006.01); C22C 38/48 (2006.01); C22C 38/50 (2006.01); F16L 9/02 (2006.01); B21B 1/02 (2006.01); B21B 1/04 (2006.01); B21B 1/46 (2006.01);
U.S. Cl.
CPC ...
C21D 9/08 (2013.01); C21D 1/18 (2013.01); C21D 6/004 (2013.01); C21D 6/005 (2013.01); C21D 6/008 (2013.01); C21D 8/105 (2013.01); C22C 38/00 (2013.01); C22C 38/001 (2013.01); C22C 38/002 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C22C 38/42 (2013.01); C22C 38/44 (2013.01); C22C 38/46 (2013.01); C22C 38/48 (2013.01); C22C 38/50 (2013.01); C22C 38/58 (2013.01); F16L 9/02 (2013.01); B21B 1/02 (2013.01); B21B 1/026 (2013.01); B21B 1/04 (2013.01); B21B 1/463 (2013.01); B21B 2001/022 (2013.01); C21D 2211/002 (2013.01); C21D 2211/005 (2013.01); C21D 2211/008 (2013.01);
Abstract

A steel pipe for line pipe has a composition of, in mass %: C: 0.02 to 0.11%; Si: 0.05 to 1.0%; Mn: 0.30 to 2.5%; P: up to 0.030%; S: up to 0.006%; Cr: 0.05 to 0.36%; Mo: 0.02 to 0.33%; V: 0.02 to 0.20%; Ti: 0.001 to 0.010%; Al: 0.001 to 0.100%; N: up to 0.008%; Ca: 0.0005 to 0.0040%; and other elements and satisfies Cr+Mo+V≤0.40, the chemical symbols in the equation substituted by the content of the corresponding element in mass %. The pipe contains tempered martensite and/or tempered bainite and further contains ferrite in at least one of a portion between a steel pipe outer surface and a depth of 1 mm from the outer surface, and a portion between a steel pipe inner surface and a depth of 1 mm from the inner surface.


Find Patent Forward Citations

Loading…