Lee Restrictor Checks incorporate a unique feature in their mechanical design. The valve is designed such that the pressure differential across the metering orifice is also located across the valve seat. This design assures that the poppet assembly moves full travel even at low flow rates. Consequently, the valve is less sensitive to silting and contamination than other designs, which may merely locate an orifice upstream or downstream of a check valve. All Restrictor Checks are protected with an integral filter screen.
Lee Directional Flow Controls are available in four different body diameters and are designed for max. operating pressures up to 8,000 psid. The valves are designed such that the full pressure differential across the metering orifice is available to move the poppet full travel. The valves also incorporate filter screens as a means of enhancing contamination resistance. Directional Flow Controls are ideal for timing applications where metering on the outlet in both directions is required. As shown below, two flow controls maintain high back pressure when the actuator is moving in either direction, thus preventing cavitation.
Lee Floserts® operate by sensing the flow rate in terms of a differential pressure across a fixed orifice. A variable-metering orifice automatically adjusts to keep this pressure, and hence the flow rate constant. Floserts are useful for controlling the velocity of an actuator under variable loads. They can increase the stiffness of a hydrostatic bearing or limit the maximum flow rate to control the speed of a pump or motor.