Development of a long duration, free swimming, inline acoustic leak detection inspection tool
Acoustic leak detection inspection tools have become a common technique to identify minute pipeline leakage before the leak and the defect producing it can become a larger problem or even a rupture level event. While these inspection tools only identify small defects once they reach the through wall stage and result in leakage, they can be an effective means of demonstrating the pressure tightness of a pipeline and ruling out the presence of through wall defects that are below the detection threshold of other ILI inspection tools; in so doing finding a way into both the leak detection and pipeline integrity toolboxes.
Enbridge Pipelines owns and operates a 12” pipeline that transports crude oil over 870KM. A majority of the line resides in permafrost conditions in a remote region, thus the window for inspections or work to be done on the pipeline is limited. Additionally the pipeline consists of long segment lengths between traps, which traverse multiple water crossings and experiences large changes in elevation. Therefore, availability, scheduling, and transport of inspection equipment are critical. The SmartBall® leak detection tool was selected for a twofold purpose: to test the technology’s capabilities, and to inspect the line specifically for any leaks.
Inspection of 3 segments of the 12” pipeline provides some unique challenges to inspection providers, requiring tools with up to 12 days of operational run-time capability and the ability to operate in product temperatures as low as -15 degrees Celsius. The generation of SmartBall tools at the time did not have the run time and data capacity required to inspect the entire length of each of the pipeline segments. As a result, Enbridge and Pure Technologies collaborated on the development of a custom, long duration, high data capacity, SmartBall acoustic leak detection tool specifically for the 12” pipeline application.