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Abstract: The present work presents plastic limit load solutions for thin-walled branch junctions under internal pressure and in-plane bending, based on detailed three-dimensional (3-D) finite element (FE) limit analyses using elastic–perfectly plastic materials. To assure reliability of the FE limit loads, modelling issues are addressed first, such as the effect of kinematic boundary conditions and branch junction geometries on the FE limit loads. Then the FE limit loads for branch junctions under internal pressure and in-plane bending are compared with existing limit load solutions, and new limit load solutions, improving the accuracy, are proposed based on the FE results. The proposed solutions are valid for ratios of the branch-to-run pipe radius and thickness from 0.4 to 1.0, and the mean radius-to-thickness ratio of the run pipe from 10.0 to 20.0. [Copyright &y& Elsevier]

Abstract: This paper investigates effects of variables related to 3-D finite element welding residual stress analyses of penetration nozzles on residual stresses. Five variables are considered; (i) number of elements in the circumferential direction, (ii) number of beads in the circumferential direction, (iii) kinematic boundary conditions, (iv) circumferential modelling angle in 3-D finite element models and (v) detailed weld shape. Based on sensitivity analysis results, guidelines for 3-D finite element welding residual stress analyses of penetration nozzles are provided. [Copyright &y& Elsevier]

Abstract: The effects of safe-end length and kinematic boundary conditions during welding on weld residual stresses in dissimilar metal welds are systematically investigated using finite element analyses for typical pressurized water reactor surge nozzle configurations. The study is generalized by idealizing complex nozzle geometries as straight pipes with two welds. The impact of these variables on axial residual stresses at inner surface is examined, since these are of most concern for primary water stress corrosion cracking. Possible mechanisms controlling the development of welding residual stresses are used to qualitatively explain the predicted behavior. [Copyright &y& Elsevier]