Infrastructure protectionA new way to detect leaks in pipes

By David L. Chandler

Published 24 June 2014

Explosions caused by leaking gas pipes under city streets have frequently made headlines in recent years, including one that leveled an apartment building in New York this spring. But while the problem of old and failing pipes has garnered much attention, methods for addressing such failing infrastructure have lagged far behind. Typically, leaks are found using aboveground acoustic sensors, which listen for faint sounds and vibrations caused by leakage, or in-pipe detectors, which sometimes use video cameras to look for signs of pipe breaks. But all such systems are very slow, and can miss small leaks altogether. Self-propelled robotic device can speed through pipes, pinpointing leaks more accurately than existing methods.

Explosions caused by leaking gas pipes under city streets have frequently made headlines in recent years, including one that leveled an apartment building in New York this spring. But while the problem of old and failing pipes has garnered much attention, methods for addressing such failing infrastructure have lagged far behind.

Typically, leaks are found using aboveground acoustic sensors, which listen for faint sounds and vibrations caused by leakage, or in-pipe detectors, which sometimes use video cameras to look for signs of pipe breaks. But all such systems are very slow, and can miss small leaks altogether.

Now researchers at MIT and King Fahd University of Petroleum and Minerals (KFUPM) in Saudi Arabia have devised a robotic system that can detect leaks at a rapid pace and with high accuracy by sensing a large pressure change at leak locations. The concept was presented at two recent international conferences, and has been described in several recent papers.

This new system “can detect leaks of just 1 to 2 millimeters in size, and at relatively low pressure,” says Dimitrios Chatzigeorgiou, a Ph.D. student in mechanical engineering at MIT and lead author of the research papers. “We’ve proved that the concept works.”

The researchers have begun discussions with gas companies and water companies — the system can also detect leaks in water pipes, or in petroleum pipelines — about setting up field tests under real-world conditions.

Chatzigeorgiou presented the concept this month at the International Conference on Robotics and Automation in Hong Kong, and at the American Control Conference in Portland, Oregon.

Current acoustic tests are only effective for detecting sound and vibration in metal pipes, Chatzigeorgiou says; plastic pipes tend to dissipate the sounds too quickly. Such systems are also time-consuming and require expert operators, he says, whereas the small robotic device he and his collaborators have developed can move as fast as 3 mph through pipes, and are almost entirely automated. Ultimately, he says, such devices could be put into a system of pipes and left in place indefinitely, conducting automatic, nonstop monitoring of the system.