Enhancing the probability of detection for small diameter ultrasonic intelligent PIGs

This work focuses on ultrasonic inspection techniques for small-diameter pipelines and tubing (ranging from 1.5 inches to 12 inches), specifically the modifications needed to enhance the detection of smaller defects and features. Inspection of pipe networks, across energy, utilities, and petrochemical sectors, is essential to ensure the safety, integrity, and efficiency of the infrastructure. Regular inspection and maintenance help prevent catastrophic failures, reducing the likelihood and severity of process safety incidents that can affect people, assets, the environment, and business reputation. Greater scrutiny from key stakeholders requires owners and operators to have robust processes in place to guarantee piping integrity. As a result, the need to detect smaller defects in smaller diameter pipes with greater accuracy is growing. Inline inspections offer the most comprehensive coverage of pipe networks. Intelligent PIGs (Pipeline Inspection Gauges) are deployed to travel along pipelines and tubing, collecting data on the condition of the pipe walls. The concept of probability of detection (POD) is introduced as a key metric in evaluating inspection system performance. This paper discusses methods to enhance the POD in ultrasonic PIGs, including increasing transducer density and applying advanced signal processing routines. Furthermore, the paper explores the effects of operational parameters, such as the speed the PIG travels and capture rates, have on inspection accuracy. The development of a small-diameter phased array intelligent PIG is also presented, demonstrating novel innovation and progress occurring in small diameter intelligent PIGs. The phased array approach offers improved sensitivity and coverage, which enables the detection of smaller defects with higher precision. The technical challenges of implementing this advanced technology in smaller diameter pipes are also discussed. By addressing these challenges, this work proposes significant improvements in the probability of detecting small defects in pipe networks less than 12 inches, ultimately contributing to enhanced pipeline and tubing safety.