PR-328-203803-R01 Improve ILI Sizing Accuracy

This multi-phased PHMSA/PRCI project aims to conduct a collaborative study (pipeline operators, ILI Technology Providers (TPs), subject matter experts, and consultants) to quantitatively measure and improve the detection and sizing capabilities of current corrosion ILI systems. A data-driven approach was used which identified problematic corrosion profiles based on the review of recent Root-Cause-Analysis reports of corrosion-related failures to design and construct an ILI corrosion test string containing features having similar profiles. All such profiles were then documented using the best possible NDE techniques. Three participating ILI TPs proposed appropriate inspection tools based on limited knowledge of the integrity conditions in the test string. A series of blind pull-through tests of the ILI systems were carried out, where the TPs delivered standard ILI reports for performance evaluation. The ILI TPs receive detailed feedback identifying the detection and sizing gaps. They are given a limited sample of detailed anomaly profile data to identify potential sources of detection and sizing improvement. A second series of ILI tests are performed and the changes in detection and sizing are analyzed and quantified for each problematic corrosion profile, identifying the improvements and the remaining gaps. The results and findings of this 3.5-year long project are presented in this Report. This research was funded in part under the Department of Transportation, Pipeline and Hazardous Materials Safety Administration's Pipeline Safety Research and Development Program. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the official policies, either expressed or implied, of the Pipeline and Hazardous Materials Safety Administration, or the U.S. Government.