摘要 |
The invention relates to vanes used in butterfly valves utilized in fluid control systems requiring special relationships between passing fluid and vane rotation and furthermore can provide leak proof shut-off when in the closed valve position and due to the extended contact length between the vane and the valve bore assures low opening friction. The invention furthermore features a shape that greatly reduces the customary high dynamic torque created by fluid suction effects on a vane when in the open position.
|