Throttle Check valves are used where volume flows have to be infinitely controlled in one direction while allowing for free flow in the reverse direction. A typical use is the speed control of cylinder or other actuators. The free flow check allows for meter-in or meter-out actuator control.
A fine tread on the adjustable throttle reveals an annular gap or triangular notch. The adjusted throttle cross-section produces a pressure drop which determines the volume flow. The volume flow is zero when the throttle is screwed in (the metal sealing edge seals completely). The in-built check valve allows free flow in the reverse direction.
Hardened and ground spindles with machined and hardened seats give excellent flow characteristics with zero leakage. The sealed adjuster provides leak-free adjustment. The locking screw allows the flow to be set and locked.