From Enbridge site ... FOX-TEK’s Electric Field Mapping (EFM) technology monitors pipe walls for internal corrosion
It’s highly accurate, it’s non-intrusive, it’s continuous and it goes with the flow.
Electrically speaking, that is.
For the past decade, Electric Field Mapping (EFM) technology—developed by Toronto-based FOX-TEK Canada Inc.—has been helping to keep Enbridge’s pipeline network healthy and fit for purpose by staying “current,” in a manner of speaking.
“If you put your finger in a stream, the water goes around your fingers. And that’s essentially how our EFM technology works,” says Allen Lone, President and CEO at FOX-TEK Canada Inc., a subsidiary of Augusta Industries Inc.
“Based on a continuous EFM monitoring system, we’re measuring the minute changes in electrical current density through a segment of the pipe where our sensor array is mounted,” adds Lone. “If there are any localized changes in the pipe wall—such as metal loss due to corrosion—our EFM system will detect a change in the current density.”
FOX-TEK’s EFM technology, as well as the company’s fiber optic-based optical strain gauges and sensor cable-based leak detection systems, are used all over the world—on anything from tanks and vessels to overpasses and bridges to refineries and electrical towers.
For energy pipelines in particular, EFM is a complementary technology that can be used to supplement a pipeline operator’s inspection and maintenance tactics.
Where a high-tech in-line inspection (ILI) tool has detected a localized area of minor internal corrosion that warrants monitoring, FOX-TEK will install an array of up to 200 wired metal pins, reflecting the size and the shape of the affected area, to monitor changes in the pipe wall’s electrical field.
https://www.enbridge.com/stories/2017/september/fox-tek-electric-field-mapping-continuous-pipeline-monitoring