Novel Techniques for Sealing Leaks of Sulfur Hexafluoride (SF6) Gas: Saudi Energy (SE) Field Application

Sulphur hexafluoride (SF₆) gas is widely used in gas-insulated substations (GIS) due to its superior insulation and arc-quenching properties, particularly in medium- and high-voltage equipment. Careful use and continuous monitoring of SF₆ are essential, as gas leaks can negatively impact both equipment performance and the environment. Traditional methods for repairing gas leaks have several drawbacks, including lengthy procedures, extended equipment outages, and challenges related to the availability and cost of original parts. To address these issues, the Saudi Energy (SE), in collaboration with the Electric Power Research Institute (EPRI), applied a lab-tested, innovative sealing technique at a 380kV GIS substation in Saudi Arabia national grid. This technique is low-cost, simple, and quick to apply—while the equipment remains in service. This paper presents the novel SF₆ gas leak sealing technique and outlines the stages of its site application. The results demonstrated significant benefits, including 80% and 59% annual reductions in gas refilling quantities over two years, along with enhanced reliability, as no equipment shutdown was required for maintenance.