Pneumatic solenoid valves are electromechanical devices that control the flow of air & are used for controlling pneumatic actuators.When a pneumatic solenoid valve is activated, a wire coil, located on the outside of the solenoid, creates a magnetic field in the solenoid core that causes the plunger to move to close or open the flow of a system. There are several typical types of pneumatic solenoid valves, including direct-acting, pilot-operated & two-way.