Validating the Threat of SCC With an Alternative, Economic and Reliable Method: SCCScreen™

With ever-aging pipelines, the threat of SCC to pipeline operators has never been taken more seriously. High profile failures have prompted the USDOT to issue an advisory to operators of hazardous gas and liquid pipelines. The advisory, dated October 2003, requires pipeline operators to determine the susceptibility to SCC along their pipelines, and, to identify and manage SCC in segments where conditions indicating such susceptibility are found. CEPA recommendations provide guidelines to operators for the susceptibility assessments, validation and mitigation methods based upon the significance of the SCC found. Hydrotesting, SCCDA and In-Line Inspection (ILI) are traditional methods that can be used to validate the SCC threat. SCCScreen™ is an alternative threat validation method, which provides both a reliable and an economic option. Complying with both the USDOT SCC Advisory and CEPA recommendations, SCCScreen™ is the result of combining the latest ILI analysis techniques with historic SCC database and studies. Unique post ILI algorithms have been developed to target the signal characteristics intrinsic to SCC colonies. This reduction in data analysis effort enables a quick and economic answer to SCC threat validation. The use of proven Crack Detection ILI tools with an extensive database of crack detection history enables the quantification of its reliability. The methodologies are validated on over 20,000 Kms of crack detection data from the Ultrasonic Crack Detection (USCD) Tool. This paper describes the SCCScreen™ methodology from concept to reality. Validation of results will be demonstrated using previous inspection runs and more recent case studies.