Discharge and Torque Characteristics, 198-Inch Butterfly Valve,Auburn Dam,

摘要

A new cast-and-welded design was proposed for the leaves of butterfly valves to be used as guard valves upstream from hydraulic turbines. Model studies were made to determine the head loss through the valve with the leaf fully opened for a valve with a straight-through body,and one with an expanding-contracting body so constructed that the flow passage area through the valve gradually decreases in the direction of flow. Geometrically similar butterfly leaves were used in the test valves. Head loss coefficient for the valve with the expanding-contracting body was about 71percent less than the loss coefficient for the valve with the straight-through body. Discharge and torque coefficient charts were determined for a full range of valve leaf positions for the valve with the expanding-constracting body.