A 40" pipeline over 400 km (250 miles), that is integral to its operator’s services, required in-depth ILI. As part of the operator’s ongoing integrity management program, it conducts cyclical crack and corrosion inspections. Due to an existing relationship and trust in its data accuracy, the customer utilized NDT Global’s new highest resolution ultrasonic crack and metal loss inspections services. This pipeline operates at high capacity and has minimum throughput requirements to meet, even during inspection, which presented a challenge for an ILI.
In order to protect the environment, the operator must explore and leverage advances in technology to provide better quality pipeline integrity information. NDT Global completed tests to evaluate if doubling the axial and circumferential resolution would lead to more reliable corrosion and crack feature identifications respectively. The operator delivered a spool of pipe to the testing yard at NDT Global where pull tests were performed at these higher-resolutions. The test pipe included a range of small pitting corrosions with diameters in the lower range of the tool performance specifications.
NDT Global demonstrated the Evo Series ultrasonic metal loss inspection tool's capability to detect and size challenging small pitting corrosions, down to 5 mm (0.2 in.) in diameter. Also, to combat the threat posed by cracks or crack-like anomalies, NDT Global illustrated the sizing capabilities and specifications of its ultrasonic crack inspection tool with highest resolution. Pipeline integrity must be safeguarded while transporting crude oil at almost maximum throughput. Normal transmission speed is approximately 2 m/s (4.47 mph). During short windows of scheduled maintenance, speed can be reduced, but no lower than 0.9 m/s (2 mph). This is not an issue with older technologies or even standard ultrasonic technology (UT) but it is a challenge for the extremely high resolutions that the operator was seeking.