A Burst Capacity Model for Corroded Pipelines Subjected to Combined Internal Pressure and Longitudinal Compression

Abstract

The present study proposes a new semi-empirical burst capacity model for corroded oil and gas pipelines under combined internal pressure and longitudinal compression. The proposed model evaluates the burst capacity of a corroded pipeline under combined loads as the burst capacity of the pipeline under internal pressure only, which is developed in a recently completed study, multiplied by a correction factor to account for the effect of the longitudinal compression. Extensive parametric elastoplastic finite element analyses (FEA) are carried out, the results of which are used as the basis to develop the correction factor as a function of the corrosion defect sizes and magnitude of the longitudinal compressive stress. The proposed model is validated by a large set of parametric FEA and full-scale burst tests reported in the literature and is shown to provide marked improvements over two existing models, the DNV and RPA-PLLC models, for corroded pipelines under combined loads.