The Burling Valve Electro-Pneumatic Proportional Flow Valve, BVFCV, employs a parabolic valve plug so that the area of valve opening is proportional to valve position.
For example; if valve position is 50% of full stroke, Cv is 50% of maximum rating. Valve position is electronically closed loop controlled, with an LVDT that provides continuous feedback to the control module. LVDT and control module are integral to the valve actuator.