The Series 486 inflatable seated butterfly valve from Posi-flate features a fully machined 316L stainless steel housing. The single piece disc and shaft is available in a number of materials including 316L stainless steel and hastelloy. The disc may be polished to a mirror finish or coated with PTFE, nylon or other high performance coating. The stainless steel valve is ideal for powders, granules, slurries and liquids and is available in sizes 2" (50mm) to 20" (500mm). Typical applications include loading and unloading of process material, sterile air control, and outlet valves for storage containers or hoppers. The inflatable seat design of the Posi-flate butterfly valve provides a better seal by utilizing air pressure to expand the seat against the disc, providing more sealing area and an even pressure distribution against the disc every time. The seat automatically compensates for wear when it inflates against the disc, extending valve life considerably.