The pneumatic actuator is the most popular valve actuator and this mainly thanks to its short switching times and high operational reliability. Both multi-turn valves and quarter turn valves can be equipped with a pneumatic actuator.
There are two models: the single-acting and the double-acting. Fluxer distributes pneumatic actuators of the brand El-O-Matic.
With all pneumatic actuators, compressed air is sent under a certain pressure into an enclosed space where the diaphragm or piston, via a connecting piece, ensures that the valve is controlled.
With single-acting actuators, the compressed air is only controlled on one side of the diaphragm or piston and your valve is thus placed in the open/closed position. When the compressed air is lost, a spring package causes the valve to return to its original position, also known as the fail-safe position.
Double-acting pneumatic actuators do not have a spring package and there is an alternating supply of compressed air along both sides of the diaphragm or piston. However, the air must also be removed from the chambers when a reverse stroke is required. In this case, an electromagnetic control valve ensures the alternation in these cycles. If the compressed air is lost, the valve remains in the same position.