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.
Significantly, EFM systems are:
Enbridge is continuously looking for opportunities to employ existing technologies, and advance new ones, in the areas of design, construction, operations and maintenance, to keep our pipelines safe.
“Crude oil transmission pipelines are typically at low risk of internal corrosion due to the cleanliness of the transported products, as well as their high flow rates,” says Trevor Place, a senior engineering specialist with Enbridge’s liquids pipelines division. “Nevertheless, over the very long term, there may be periods when accumulated sediment and water have caused corrosion. These locations are easily detected through our in-line inspection programs, and some of these may become suitable for supplemental monitoring using EFM technology.
“Because they’re real-time and continuous,” adds Place, “FOX-TEK monitoring systems are capable of a high level of precision—and they provide validation for our ongoing mitigation activities, like interior cleaning or chemical additives that minimize bacteria and prevent corrosion.”
FOX-TEK’s EFM technology is currently providing continuous monitoring at several locations along Enbridge’s 18,666-mile (30,040-km) North American crude oil and liquids network.
“Because the EFM system is monitoring the actual pipe wall, there really is no better representation of what’s happening inside the pipe,” says Place. “FOX-TEK has been a solid performer for Enbridge for years.”