Are your pneumatic cylinders hard to control? Are they lunging and moving erratically? Controlling the speed and operation of your pneumatic actuators is key to a system operating smoothly and consistently. This will enable your equipment to produce consistent products and last longer due to a smooth controlled movement.
Flow control valves are special fittings designed for use in pneumatic systems. These valves come with an adjustable orifice that can be adjusted by the machine operator.
Flow control valves are used to reduce the flow rate from a pneumatic actuator. This valve serves to decrease the operational speed of a pneumatic actuator. A needle valve, while similar to a flow control valve, controls the flow in two directions (in and out of an actuator), a flow control valve is used to adjust the air flow in only one direction. This way, free flow of air is allowed in the opposite direction. This enables a cylinder to have a controlled move in one direction, but full flow and speed in the opposite direction.
This diagram shows the flow path for a flow control valve. It allows for controlled flow in one direction and full flow and speed in the opposite direction.
This diagram shows the flow path for a needle valve which controls flow in both directions which will adjust the speed of an actuators extend and retract stroke.
The threaded adjustment of the valve ensures gradual and easy adjustment of the quantity of controlled air that is allowed to pass through a valve. There are two types of flow control valves that are used in pneumatic circuits. The selection and installation of these two types of flow control valves has a great impact on the actual functions of an actuator.
- Meter Out Valve – It is a common type of control valve which is used to control the exhaust flow that is released from the actuator. These valves are commonly used for double acting cylinders and are more advantageous to control the speed of the actuator due to the natural compressibility of air.
- Meter In Valve – Also called the reverse flow control valve, is used to restrict the flow to the actuator itself. These valves are commonly used to control the speed of a cylinder that has only one pressure supply. i.e. if the actuator has a spring to extend or retract the actuator automatically.
If you have a pneumatic system that’s moving too quickly or erratically, we can help you control your actuators to help your equipment to deliver more consistent products and have a longer life cycle.