L51631 Methods for Prioritizing Pipeline Maintenance and Rehabilitation

As pipelines continue to age they may be affected by time-dependent degradation such as continuing metal loss resulting from corrosion and other factors affecting the integrity of the pipeline. Pipeline operators need to perform timely inspections, repairs or pipe replacements to prevent leaks or ruptures. An effective means for the pipeline operator to carry out such remedial actions within the limits of the finite resources available is to perform a risk assessment. Basically, this entails scientifically prioritizing inspection, repair, or replacement of the various parts of the pipeline system in a manner that achieves an acceptable level of safety while effectively allocating the available resources. Because there is no single “right” way to conduct risk assessment, the industry needs guidance regarding the methods and information required to conduct one. Battelle specialists conducted a comprehensive research project described in a final report along with a basic risk assessment software application. The project involved the following: Review of Risk Assessment Methods Identification of Risk Parameters and Assessment of Their Significance Identification of the Factors Affecting the consequences of Accidents and Their Impact Development of a Risk Assessment Algorithm Sample Calculations & Testing Critical Assessment of Risk Analysis as a Means of Utilizing Pipeline Monitoring Tools and Rehabilitation Techniques The work included a review of 14 references describing various approaches to examining the risk of failure in pipelines followed by a summary of methods. An Analysis of a results questionnaire sent to all PRCI member companies is included and a discussion of the statistical concepts that may be of value in conducting a risk assessment. A final algorithm and sensitivity of the key parameters is examined and examples of use of the algorithm are given.