Comparison of Stress Intensity Factors of a Pipe with an Inside Surface Semi-elliptical Flaw under Global Bending

Abstract

In order to revise the closed-form stress intensity factor K_I for internal circumferential surface flaw subjected global bending in ASME Section XI Appendix C, the K_I coefficient G_bg of JSME rules on Fitness for Service 2012 edition and API 579-1 2007edition were compared by adding the similar comparison of the coefficients G₀ and G₁. From the comparison of the tabular data of both codes, the overall consistency was observed except for one data of G_bg for inner radius R_i /thickness t =1, which was corrected in 2016 edition. Based on the comparison results, the closed-from equation will be established and introduced into ASME Section XI Appendix C.