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:
Aug. 26, 2008
Filed:
Mar. 25, 2005
Nobutoshi Murao, Wakayama, JP;
Nobuyuki Hisamune, Wakayama, JP;
Hajime Osako, Wakayama, JP;
Kunio Kondo, Sanda, JP;
Nobutoshi Murao, Wakayama, JP;
Nobuyuki Hisamune, Wakayama, JP;
Hajime Osako, Wakayama, JP;
Kunio Kondo, Sanda, JP;
Sumitomo Metal Industries, Ltd., Osaka, JP;
Abstract
A high strength seamless steel pipe having mgh yield stress and excellent hydrogen-induced cracking resistance, comprises by mass %, C:-%, Si:-%, Mn:-%, p:% or less, S:% or less, Ti:-%, Al:-%, Cr:-%, Mo:-%, V:-%, Ca-%, N:% or less and O (Oxygen):% or less, the balance Fe and impurities. The steel microstructure is bainite and/or martensite and ferrite is precipitated at grain boundaries. The seamless steel pipe can contain at least one of Cu:-% and Ni:-%. To produce the pipe, it is desirable to limit a starting temperature of quenching after rolling, a cooling rate and a tempering temperature.