Epri has developed an app for droid tablets that allows nuclear plant operators to understand air operated valve aov components.
Air operated valve diagram.
Shown in the de energized condition.
These valves close all ports in the off position to stop equipment in a locked position with air pressure holding it in place.
Mechanical and air operated valves.
Fluid power valves when electrically operated by a solenoid are drawn in the de energized position.
The compressed air in this cylinder pushes against the piston and actuates the solenoid to switch the valve.
The 2 way air operated valves can be either normally closed or normally opened.
5 3 air operated valve pressure center.
Types are 2 way 3 way and 4 way.
Note that in figure 24 the operator of the valve is not identified but like a standard process fluid valve the valve could be operated by a diaphragm motor hydraulic solenoid or manual operator.
Manual override knob detented air pressure shifts the valve electric on axle down 1.
Mechanical and air operated valves.
This pilot valve is a small direct operated 3 2 way valve.
Energizing the solenoid will cause the valve.
In this type of valve air pressure is applied through a pilot valve into the actuator which in turn raises the diaphragm and opens the valve.
The pilot valve delivers compressed air to a small air cylinder inside the valve.
Directional air control valves are the building blocks of pneumatic control.
4 way solenoid spring return air operated manual internal override dual pressure application.
Pneumatic circuit symbols representing these valves provide detailed information about the valve they represent.
Manual pneumatic hydraulic electric etc.
When energized the valve will shift it s flow paths and lower the axle.
In order to do this an additional pilot valve is used.
5 3 air operated valve with integrated check valve.
This video offers a glimps.
The most common diaphragm valves use pneumatic actuators.
As solenoids are not used heat is not generated by the actuator making them suitable for use with fluids sensitive to changes in temperature.
These are pneumatically driven valves.
Internal pilot 1 8 3 5 2 4.
Diaphragm valves can be controlled by various types of actuators e g.
Also known as 4 way and 5 3 closed center valves.
They can also be used in environments unsuitable for electric devices such as inflammable atmospheres.
They create two actions and have two exhaust ports which allows you to control the speed of each action by attaching a flow control valve to each exhaust port.
Symbols show the methods of actuation the number of positions the flow paths and the number of ports.
