Single Acting (Fail Close) / Single Acting (Fail Open)
Single acting actuators convert pneumatic energy into mechanical energy to produce work. This is usually only carried out during the forward stroke movement of the actuator. The actuators force (lbs) which is exerted via the piston and the piston rod which increases in accordance with the piston area expressed in (in2) and the air pressure in the actuators chamber. Usually the force to return the piston is a mechanical spring; this is normally accomplished when air is exhausted from the actuator. However, in some pneumatic applications when using pneumatic single-acting actuators the spring may be place on the piston end to allow the actuator to snap into place, example shot pins, when the air is shut off. This usually occurs when emergence “E”-stops application are energized on the machinery.

• Normally used in on/off applications

• Valves open or close (pre-determined) in case of power or air failure

• Fail safe position : close / open as pre-determined (depending upon customer requirement)

• Only one Air Inlet Port

• 3/2 Solenoid Valve is used for air supply

• Air to Open / Spring to Close

• Air to port A forces the piston outwards causing the springs to compress; the pinion turns counterclockwise while air is exhausted from port B.

• In the event of loss of air pressure on port A, the stored energy in the springs forces the piston inwards. The piston turns clockwise while air is exhausted from port A.