Corrosion is one of the most important damage mechanisms for pipelines in service and existing engineering standards for evaluating the integrity of corroded pipelines such as the ASME B31 G criterion are based on the deterministic approach. In this study, a probabilistic model for the assessment of the reliability of corroded pipelines is presented. The merit of the probabilistic approach to residual strength assessment is demonstrated via the application of a probabilistic version of the ASME B31 G criterion which is widely used in the pipeline industry. In particular, probabilistic sensitivity studies are used to identify the most important engineering parameters m selected engineering models for corroded pipes. It is shown that these studies give useful insight regarding the modelling aspects and engineering parameters of the empirical/semi-empirical models that require detailed or accurate determination in practical engineering applications.
Corrosion is one of the most important damage mechanisms for pipelines in service. These include gas and oil transmission pipelines as well as offshore pipelines, which are all prone to external and internal corrosion, localized (pitting) and general corrosion. Two main strategies have been employed by operators to ensure the continued, safe operation of corroded pipelines. These consist of the use of hydrostatic testing or the application of industry-accepted analytical corrosion-assessment criteria. The use of hydrostatic testing to demonstrate pipeline integrity under operational loads IS usually expensive. This economic disadvantage has been documented by Shannon and Argent (1989), for example. The second option which relies on the application of empirical and Semi-empirical analytical methods to assess the integrity of corroded pipelines is more cost-effective. This latter approach has been favoured by the pipeline industry and its application for making repair or replacement decisions has saved millions of dollars.
