Girth Welded Joint Of Steel Pipe

Abstract: Provided is a girth welded joint of steel pipe 10 including base metal portions 1a, 1b and a girth welded portion 2, wherein the girth welded portion 2 is formed of a weld metal portion 2a and weld heat affected zones 2b, 2c, the base metal portions 1a, 1b have a predetermined chemical composition, Pcm is within a range of 0.25 to 0.30, the weld metal portion 2a has a predetermined chemical composition, a content of B is 0.0010% or less, each of tensile strength of the base metal portions 1a, 1b and tensile strength of the girth welded portion 2 in a cross weld tensile test is 980 MPa or more, average hardness of the base metal portions 1a, 1b is 300 HV10 or more, an average softening width of the weld heat affected zones 2b, 2c is 4.0 mm or less, and an average softening degree is 80 HV10 or less.

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