PR-218-063511-R01 Inventory of Types of Mechanical Damage Experienced by Gas and Oil Pipelines

The project focused on compiling an inventory of mechanical damage experienced by gas and oil pipelines to ensure that the capability or applicability of models being developed or used to predict pipe behavior in the presence of mechanical damage are representative of actual experience.  The inventory was developed through the use of a survey sent to a variety of pipeline operators requesting information regarding mechanical damage incidents reported through both in-line inspection operations and field dig reports.  The information provided included the type of mechanical damage experienced, the possible source of the damage, the significance of the defects in terms of whether or not they resulted in leaks or ruptures, and how frequently they occur on pipelines of various sizes and grades.  The result of this work has at least two important uses.  In the short-term, the results can be used on a related project, MD-2B, which is intended to develop a model for ranking severity of ILI indications associated with mechanical damage and dents from the standpoint of response times for remediation.  In the longer term, the results can be of use to model developers who are trying to develop or improve mechanics-based models for predicting the failure pressure levels of mechanically damaged pipe segments.