The uniqueness of the Series 7700 Butterfly Valve begins with the sphericalbore of the disc seat area. This facilitates a constant DISC-TO-SEAT loading that maintains a leaktight stem seal regardlessof disc position. The stem sealing force is constant through the full disccycle and operating torques are kept low which increases valve life. The design provides a bubble tightseal from full vacuum to 300 psi when the valve is closed. The valve is rated for dead-end service toa full pressure rating of 300 psi.
