A prototype sensor that can quickly and cost-effectively measure pitting and deterioration of natural gas pipelines has moved one step closer to being commercialized, the Department of Energy (DOE) said last week.

Known as the “conformable array,” the sensor provided accurate, automated measurements of corrosion on the exterior of pipelines during a recent field test carried out by the Southwest Research Institute (SRI) in San Antonio, TX. The sensor is being developed by the institute, in cooperation with the DOE’s National Energy Technology Laboratory (NETL) and Houston-based Clock Spring Company LP, which is known for its patented clock spring method of repairing and reinforcing damaged gas and liquid pipelines.

The sensor is “roughly six months” away from being commercialized, said Dan Driscoll, a DOE project manager. He noted that Clock Spring “in all likelihood” will manufacture the product.

This next-generation sensor is a major improvement over the existing methods for detecting external pipeline corrosion, said Richard Baker, who manages the project for NETL. “Traditional technologies use manual measurements, while the new sensor is computerized and automated. This jump in technology means faster, more accurate and less expensive corrosion measurements.”

The project was launched in response to the Bush administration’s national energy policy goal of a more modern energy infrastructure. The DOE estimated that there are 1.2 million miles of gas transmission and distribution pipelines crisscrossing the nation. “The operational integrity of every foot of these pipes is crucial to ensure continuing service,” Baker said.

External pipeline corrosion occurs when water, condensation, scratches or other actions damage a pipe’s protective coating and sensitive joints, the department said. Like rust on a car, pipeline corrosion can extend far down into the metal, well beyond the visual signs on the surface. DOE’s Driscoll acknowledged that internal pipeline corrosion “is a big problem” as well, but he said the sensor “isn’t something that could be used with current inline inspection tools.”

The traditional method for spotting pipeline corrosion requires excavation to expose a pitted section of pipe, sandblasting to remove all dirt and debris, then manual measurements by a technician using a hand-held gauge and bridging bar. This method is time-consuming and expensive, and the results are subject to the technician’s interpretation, the DOE said.

The prototype sensor also requires that a pipe be exposed, but it does not call for sandblasting. This substantially reduces costs and the time involved in the investigation, the DOE noted. And because the method is automated, it eliminates individual interpretation and improves accuracy. Although the initial cost of the senor would probably be more expensive than current detection technology, Driscoll said savings will be realized through reduced manhours.

The flexible sensor is about six inches square, and designed to conform to the contours of a pipe. Two rigid circuit boards, each about three by six inches, attach to the sensor at opposite ends, making a rectangular unit about six by 12 inches. Suitable for field use, the unit is applied to a pipeline’s exterior, and the senor takes an image of the overlaid area. The unit is then moved, and new images taken, until a picture has been produced of the pipe’s circumference.

The data is transmitted 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. The analysis is used to assess the strength and integrity of the pipeline, and the pipe can be repaired, replaced or monitored as needed.

For more information, go to NETL’s website at https://www.netl.doe.gov. Parties can also log on at https://www.clockspring.com.

©Copyright 2003 Intelligence Press Inc. Allrights reserved. The preceding news report may not be republishedor redistributed, in whole or in part, in any form, without priorwritten consent of Intelligence Press, Inc.