SCC In-Field Inspection Technology Evaluation and its Application to EMAT Based Pipeline Integrity Management Programs

Abstract

Most recently, as a complement to the ongoing efforts to monitor and document improvements in EMAT ILI technology, PRCI conducted an extensive study of NDE inspection technologies for characterizing SCC in pipelines using various in-ditch technologies and methods. The test pipes used for the study were cut outs from an operating pipeline where SCC features were identified and sized using EMAT ILI technologies. These are now sized with the NDE study and correlated with EMAT data to support an improvement of EMAT technology in characterizing SCC features. More importantly, the test pipes were burst tested to failure, with post failure analysis completed to fully characterize the crack features, including detailed length and depth measurements. This complete data set provides a comprehensive view of the current capabilities of NDE inspection technologies and EMAT ILI technologies to detect and characterize SCC and crack-like features. In this paper, the approach used for the evaluation of in-ditch NDE and EMAT ILI technologies is presented first. The in-ditch NDE technologies used for evaluation which were commonly used for SCC characterization are then described. SCC characterization results from in-ditch NDE and EMAT ILI are summarized and compared to those directly measured from fracture surfaces exposed by burst tests. The findings and its application to pipeline integrity management programs are discussed.

Literature Review: Theory and Application of In-Line Inspection Technologies for Oil and Gas Pipeline Girth Weld Defection

“…In 2008, Pipeline Research Council International (PRCI) initiated a program for assessment of EMAT in-line inspection performance, and employed the technologies including magnetic particle, ultrasonic inspection, phase-array ultrasonic imaging and crack interruption to compare the size of a pipeline defect from EMAT in-line inspection with the data of field excavation inspection [ 84 ]. After comparing the EMAT and non-destructive evaluation (NDE) data of the crack surface for one crack, the crack outline was consistent in both inspections, and the maximum crack depth was within the deviation ±1 mm.…”