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:
Jul. 07, 2026
Filed:
Oct. 25, 2022
Nippon Steel Corporation, Tokyo, JP;
Akira Doi, Tokyo, JP;
Takeshi Miki, Tokyo, JP;
Hiroyuki Nagayama, Tokyo, JP;
Naoki Kuroda, Tokyo, JP;
NIPPON STEEL CORPORATION, Tokyo, JP;
Abstract
A girth welded joint of steel pipeincludes base metal portionsand a girth welded portion, wherein the girth welded portionis formed of a weld metal portionand weld heat affected zones, the base metal portionshave a predetermined chemical composition, Pcm is within a range of 0.25 to 0.30, the weld metal portionhas a predetermined chemical composition, a content of B is 0.0010% or less, tensile strength of both base metal portionsand tensile strength of the girth welded portionin a cross weld tensile test is 980 MPa or more, average hardness of the base metal portionsis 300 HV10 or more, an average softening width of the weld heat affected zonesis 4.0 mm or less, and an average softening degree is 80 HV10 or less.