All 1.2 million miles of natural gas pipelines that crisscross the United States are subject to corrosion caused by condensation, pressure, and other factors. Unfortunately, integrity examinations require excavation, sandblasting, and manual measurements. A new sensor eliminates most of this work, though: Technicians can simply excavate a suspected length of pipe and apply the conformable array.
This flexible sensor comprises two rigid circuit boards, each about 3 by 6 inches, that attach to the sensor at opposite ends to form a rectangular unit measuring about 6 by 12 inches. Technicians apply the unit to the pipeline's exterior, and the sensor takes a picture of the overlaid area. The unit is then moved and new images are taken.
The array transmits data to a computer in real time through a cable attached to one of the circuit boards. The computer forms a composite image of corrosion from the individual snapshots and analyzes the extent of the damage. Gauging the pipe's strength and integrity, technicians can determine if the pipeline needs to be replaced, repaired, or simply monitored.
The device, developed by the Southwest Research Institute in cooperation with the Clock Spring Company and the National Energy Technology Laboratory, was field-tested by the Department of Energy. Expect its commercialization in the near future. Also, the conformable array likely will play a role in the Office of Fossil Energy's comprehensive pipeline infrastructure reliability program.
For details, go to www.netl.doe.gov.