Development of novel integrated in-line inspection techniques for pipeline inspection

Abstract

This paper proposes a new, low cost, and high sensitivity smart pipeline inspection gauge (smart PIG) that integrates different in-line inspection (ILI) techniques to inspect the pipeline defects such as dents, metal loss or corrosions. The proposed ILI techniques include: (1) optical sensor (based on photoconductivity); and (2) bimorph sensor (based on piezoelectricity). Laboratory tests are conducted on various types of defects such as convexities (e.g., deposit corrosion) and metal losses (e.g., cavity corrosion) to demonstrate the validity of the proposed techniques. Furthermore, the conventional magnetic flux leakage (MFL) technique is developed to verify the effectiveness of the proposed ILI techniques. The test results show that the proposed ILI techniques can effectively identify the defect position. It is envisioned that the developed smart PIG has significant potential for real-time inspection of the long-buried pipeline.