Purification is critical because SF₆ — after use — may contain moisture, air, oil mist, particulate contamination, or decomposition by-products (from previous arcing or exposure). Such impurities degrade SF₆’s dielectric and arc-extinguishing properties and can accelerate corrosion or compromise long-term reliability. https://www.yunengoilpurifier.com/sf6-gas-purification-machine