Sulfur Hexafluoride, or SF6, gas leak testing is the newest in a series of innovative services being offered by Premier Utility Services LLC, a wholly-owned subsidiary of Willbros Group, Inc., to assist electric utilities in reducing overall maintenance cost, increasing reliability scores and protecting the environment.
SF6 gas can be found in millions of electric equipment installations all over the world. The gas also poses a recognized environmental pollution risk with a global warming potential of 23,900 times that of CO2.
"This gas, known primarily for its insulation properties in utility substation circuit breakers, can leak at mechanical fittings and couplings. If too much SF6 gas leaks, a catastrophic failure of the breaker can occur, costing over $100,000 to repair and resulting in localized outages," said Marc Makely, president of Premier.
Don Daly heads up the new SF6 testing service at Premier. "Leak testing is done using a special infrared camera capable of detecting even the smallest of pinhole leaks," said Don, "and it does not take long for pressurized gas to escape from these openings. Modern cameras are capable of detecting leaks as small as two pounds per year."
Don has extensive experience in SF6 leak detection, having previously headed up a survey team at a utility research institute. In 12 years of testing, he has traveled extensively in North America and South Africa looking for these gas leaks.
The key to this service is recent innovations made in gas leak detection cameras. Surveys that previously may have taken hours or days using a handheld gas sniffer can now be performed in minutes and from a safe working distance. "In the past, leaks have been detected using a "sniffer" device or a soap and water mixture to identify the leak location," said Don. "The sniffer can sometimes be difficult to use in tight locations and it's a contact type instrument requiring the user to take the equipment out of service to "sniff" for leaks near the high voltage circuit. The same is true for soap bubble leak detection methods. Premier utilizes a state-of-the-art infrared camera to scan the equipment from a safe distance. The camera displays a gas leak as a dark plume of smoke in the infrared image. The use of this type of camera rather than the older laser imaging, sniffer, or soap indication type systems makes the inspection process safer and more efficient."
Premier offers entire substation system leak surveys as well as spot check services that focus on specific or suspected trouble areas.