Effect of Dents and Gouges on the Integrity of Pipelines

摘要

A 1993 hazardous liquid pipeline failure in Reston, Virginia and a 1994 gaspipeline failure in New Jersey are thought to have been caused by prior outside damage occurring several years before the failures. The type of damage visible on the failed pipes consisted of scrapes or gouges and may have been associated with dents caused by some machinery such as backhoe or bulldozer. This report examines the literature associated with dents and gouges in pipelines and similar shell structures. An analysis of rerounding of the damaged area is also carried out. It is concluded that dents in large pipelines are likely to reround under pressure and are, therefore, fairly innocuous. However, gouges and cracks associated with rerounded dents are not innocuous due to the superimposed residual stress field and should be removed if they are detected.