The eccentric action of the plug keeps the plug off the seat for virtually the entire throttling range which minimizes friction internal to the valve. The seat portion of the plug has the form of a spherical segment and is rotated through a nominal 50 degree angle. The center of the plug is offset from the shaft axis. As a result, the shaft rotates the plug in an eccentric "cam" motion. However, no plug to seat contact is made until the moment of seating. The leading edge of the plug contacts the seat first and additional actuator thrust moves the plug down and forward into the seat. The positive seal between the plug and the seat is achieved by the elastic deformation "flex" of the plug arms, which imparts a direct compression load to the seat for repeatable tight shutoff.
Dynamic performance testing shows conclusively the ability of the Camflex to make accurate changes in flow response to very small changes in input signal. Other tests on the Camflex valve have demonstrated exceedingly low running torques (approx. 2% of actuator span) that validate claims of minimal internal frictional forces.