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.
Patent No.:
Date of Patent:
Nov. 30, 2021
Filed:
Oct. 18, 2016
Applicant:
Jfe Steel Corporation, Tokyo, JP;
Inventors:
Assignee:
JFE Steel Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C21D 8/10 (2006.01); C22C 38/32 (2006.01); C22C 38/54 (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 38/20 (2006.01); C22C 38/22 (2006.01); C22C 38/24 (2006.01); C22C 38/26 (2006.01); C22C 38/28 (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); C21D 1/18 (2006.01);
U.S. Cl.
CPC ...
C21D 8/105 (2013.01); C21D 1/18 (2013.01); C21D 9/085 (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 38/20 (2013.01); C22C 38/22 (2013.01); C22C 38/24 (2013.01); C22C 38/26 (2013.01); C22C 38/28 (2013.01); C22C 38/32 (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 38/54 (2013.01); C21D 2211/004 (2013.01); C21D 2211/008 (2013.01);
Abstract
The high-strength seamless steel pipe has a volume fraction of tempered martensite of 95% or more, and a prior austenite size number of 8.5 or more, and contains nitride inclusions having a size of 4 μm or more and whose number is 100 or less per 100 mm, nitride inclusions having a size of less than 4 μm and whose number is 700 or less per 100 mm, oxide inclusions having a size of 4 μm or more and whose number is 60 or less per 100 mm, and oxide inclusions having a size of less than 4 μm and whose number is 500 or less per 100 mm, in a cross section perpendicular to a rolling direction.