PR-430-133757-R01 PHMSA Comprehensive Study to Understand Longitudinal ERW Seam Failures

In 2011, the US Department of Transportation (DOT) Pipeline and Hazardous Materials Safety Administration (PHMSA) initiated a project known as the “Comprehensive Study to Understand Longitudinal ERW Seam Failures” (PHMSA Phase 1 ERW Study). The project deliverables were thirteen (13) individual ‘task reports’ and a summary report which included considerations for failure history, characteristics of ERW seams that make them susceptible to failure, fracture mechanics and fatigue models, selective seam weld corrosion, integrity assessment, and non-destructive examination (NDE) methods. As of the development of this report, a second phase of the PHMSA research program is now under way including full scale testing and validation of integrity assessment and NDE methods.

This report is a summary of an industry critical review performed by several representative PRCI member companies of the PHMSA Phase 1 ERW Study. It is recognized that a second phase of the research is currently under way by PHMSA, however PRCI’s member companies wanted to review and capitalize on relevant information and data presented in the current body of knowledge. Ultimately, this and other work performed throughout the industry will provide the foundation for developing and validating integrity management programs for pipelines constructed of vintage ERW line pipe.