On the Ratchet Analysis of a Cracked Welded Pipe

Abstract

This paper presents the ratchet limit analysis of a pipe with an axisymmetric circumferential crack in a mismatched weld by using the extended linear matching method (LMM). Two loading conditions are considered: (i) a cyclic temperature load and a constant internal pressure and (ii) a cyclic temperature load and a constant axial tension. Individual effects of (i) the geometry of the Weld Metal (WM), (ii) the size of the crack, (iii) the location of the crack, and (iv) the yield stress of WM on the ratchet limits, maximum temperature ranges to avoid ratchetting, and limit loads are investigated. Influence functions of the yield stress of WM on the maximum temperature ranges and limit loads are generated. The results confirm the applicability of the extended LMM to the cracked welded pipe.