Types of pneumatic valves

Pneumatic valves are those valves which are important for controlling the pressure, amount and the rate of air. The pneumatic system transmits power by depending on the force of compressed air. They are used in a number of places and for industrial applications as well.

Pneumatic valves are used for pressure power tools as well as in diesel engines. There may be either one or more pneumatic valves which may be present in the device. Pneumatic valve is classified on the number of ports possessed by them. Some of them have been discussed below.

Two-Way Directional Valve

In a two-way directional valve, air can pass in two directions. There are two ports which can either be opened or closed. There is no flow of air if the ports are closed. While if the valves are open, the air can flow in through either one of the ports and move through the other port or they can move in the opposite direction as well.

Directional Valve

Three-Way Directional Valve

There are three ports in the three-directional valve. All these ports have their specified purposes. The first port connects the valve to another device or an actuator. The second port is connected to an air flow and the third port is used for the exhaust of the air. The third port is closed when the first two ports are opened and the air flows in through the valves to the device. When the first and the third ports are open, the second valve is closed and the actuator can vent the exhaust. Three-way valves are paired and connected to actuators in double acting cylinders.

Four-Way Directional Valves

In four-way directional valves, there are four distinct ports among which two of them are connected to the actuators and another one’s connected to a pressurized air-flow and the last one acts as an exhaust unit. These are the most common types of pneumatic valves as four ports make it easier for the system to work efficiently and effectively. They can also reverse the motor motion or the motion of a cylinder. Sometimes, an additional port is also added to a four-way valve, which effectively makes it a five-ported four-way valve. Together, they can create dual pressure depending upon the needs of the application.


You should choose the pneumatic valves depending upon your choice and requirements.