A Methodology for Constructing Complex 3D Cracked Body Finite Element Models Efficiently

Abstract

Design code design by analysis routes often require knowledge of collapse parameters while structural integrity fitness for purpose assessments require detailed knowledge of both collapse and fracture parameters. These parameters can be calculated using detailed Finite Element Analysis (FEA) simulation. However, the process of constructing Finite Element (FE) models of complex components such as branches and branches located on pipework bends is often time consuming when considering aspects of weld design around branches attached to bends or the requirement for specialist knowledge when inserting crack-like features into FE models close to welds or areas with notable curvature such as that found in bends. This paper presents a technique which can be used to construct finite element models quickly so as to shift the effort of the structural integrity expert from modelling to assessment. This paper provides a basic procedure for creating and manipulating FE models to enable inserting cracks in areas of structural discontinuities or in areas of significant curvature. The usefulness of this method is illustrated by considering the results of 3D defect free and cracked FE analyses of pipe bends. It illustrates the use of the method to create defect free branches and can be extended to include crack in these components. The analyses reported here use the commercial FEA software Abaqus. However, this technique can be adapted to any modern FEA software. This methodology would be of particular interest to industries relying on pipework and pressure vessel components and where the failure of such component can have serious safety and commercial implications.