When a buried oil pipeline at a station on the Trans Alaska Pipeline System sprung a leak, the pipeline company faced a costly problem: Scrap the piping below ground and rebuild above ground or find technology that could inspect the original line.
The line’s structural integrity could be assessed using pipeline inspection gauges, or “pigs,” which are cleaning devices— smart pigs have sensors—that are inserted into an oversized section of pipe, called a launching station, and pushed by the oil flow to a receiving station.