Reevaluation of Burst Capacity Models for Corroded Steel Pipelines

Abstract

Abstract. Through-wall pitting is the most common failure mode of concern for high-pressure pipelines as used in the oil and gas industry, both offshore and onshore, potentially allowing loss of containment and environmental pollution. Pipe burst under pressure is also of concern, particularly in high-safety class pipelines. Semiempirical models for predicting pipeline burst capacity vary in their fidelity. Mostly, this has been estimated by benchmarking burst capacity prediction models of undefined conservatism against burst pressure derived from finite element analysis (FEA) of steel pipes with wall defects, such as those caused by corrosion. The most recent of these comparative assessments is reviewed herein, and areas of concern are noted. This is followed by a statistical analysis for performance assessment of several burst capacity models, by comparing their predictions against FEA-generated data, for which both the modeling and the input data appear to have been correctly applied. The results of the analyses allow a more accurate ranking of burst capacity models, considering both predicted mean values and estimates of variability, and provide a basis for making logically consistent comparisons. They also form a basis for the application of safety factors to provide measures of the relative probability of pressure pipe bursts.