Glossary · Pneumatics and hydraulics
Flow-control valve
Also known as: Flow control valve, Flow regulator
German: Stromregelventil
In fluid power, a flow-control valve is a valve that controls the flow rate through a line and thus the speed of an actuator; pressure-compensated types keep the flow constant largely independent of load pressure.
- Fluid power
In one sentence
A flow-control valve sets the flow rate and thus actuator speed; pressure-compensated types hold it steady despite load changes.
Example
A pressure-compensated flow-control valve keeps the feed speed of a hydraulic drilling unit constant as cutting forces change.
How it applies
- Engineering: Meter-in, meter-out and bleed-off arrangements behave differently; meter-out control is typical for pneumatic cylinders and for loads that could run away.
- Commissioning: Speeds are adjusted with the real load and then locked, where possible.
- Operation: Changing a flow setting changes speed and possibly impact forces and stopping behavior.
- Documentation: Mark adjustable flow valves in the circuit diagram, document set values and describe who may change them. In the safety chapter, note that speed settings can be relevant to the risk assessment.
Flow-control valve vs. throttle valve
A Throttle valve is a simple restriction whose flow changes with pressure difference. A pressure-compensated flow-control valve keeps flow constant over a range of pressures. In pneumatics, the term "flow-control valve" often means a throttle-check valve.