A Unified Shakedown Assessment Method for Butt Welded Joints With Various Weld Groove Shapes

Abstract

A unified shakedown assessment approach for butt welded pipes or cylindrical pressure vessels with common circumferential butt welded joints for U-groove, V-groove, X-groove, double U-groove (DU-groove), UV-groove, and single-side welding was established under cyclic thermomechanical loadings based on the simplified finite element method. Individual effects of material properties of weld metal (WM), heat affected zone (HAZ), and parent material (PM), the ratio of inner radius, and wall thickness were further considered. Results showed that the proposed method has a high accuracy for shakedown evaluation of weld pipes with various weld groove shapes. Moreover, U-groove is fit for weld pipes to improve the load-carrying capacity of thick-walled cylinders under cyclic thermomechanical loading. Furthermore, the ratio of the yield stress between WM and PM should be greater than the transition point for weld pipes with various weld groove shapes to avoid ratchet first occurs in the WM region.