InflatableSeatedButterfly Valves > SERIES 485486487488 > ANSI and MetricFlange Compatible size="-2">

Closed, unsealed As the valve rotates into the closedposition, the disc makes onlycasual contact with the seat,reducing friction, wear and torquerequirements. > Closed, sealed After the valve is closed, the seatinflates against the disc providingmore sealing surface and an evenpressure distribution against thedisc. Open, unsealed Before the valve opens, the seat isfirst deflated. The disc is then freeto rotate to the open position. >