Automatic Modeling and Analysis of Pipelines with Colonies of Corrosion Defects

Abstract

The prediction of the failure pressure (FP) of pipelines with corrosion defects is the most important issue in structural integrity analysis of high pressure pipeline systems. The Finite Element Method (FEM), provides accurate results in failure pressure prediction. However, the FEM modeling and analysis process of a single pipeline with idealized corrosion defects could take weeks, and it is very repetitive and requires highly specialized engineering. In other work Cabral, H.L.D. (2007) presents a set of computational tools called PIPEFLAW for automatic generation of Finite Element (FE) models of pipelines with idealized corrosion defects. This work presents a new option for automatic generation of FE models with corrosion defects arbitrarily located along the pipeline. These tools are based on the MSC.PATRAN pre and post-process commercial software and the data input to the pre-processor is done through a friendly graphical user interface. The ANSYS software is used for physical and geometric al non-linear analysis to obtain the failure pressure value. The FP obtained by the automatic generated models, is compared with experimental results obtained by burst tests (Benjamin et al, 2005; Benjamin et al, 2006a) and numerical results obtained by manually generated models (Andrade et al, 2006). The obtained results validate the automatic procedure and the FE models built.