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Design & Technology


Pneumatic systems use the energy stored in compressed air to do work. By controlling the release of the air to pneumatic cylinders, we can turn that energy into movement.


Pneumatic components are arranged in circuits - much like electronic circuits - using symbols for each component. You need to be familiar with the operation of two of most common pneumatic components - a single-acting cylinder with a three-port valve, and a double-acting cylinder with a five-port valve. You also need to understand how time-delayed pneumatic circuits and pneumatic logic circuits work.

Finally you need to know how to work out the force output from a cylinder.

Pneumatic symbols

In your exam, you will be asked to draw pneumatic circuit diagrams using symbols. The symbols for each of the common pneumatic components are listed below. You need to be able to recognse these symbols, and understand the function of the components they stand for.

You might find it helpful to print off this page and keep it for reference.

a chart of the standard symbols used in Pneumatics. It shows the common symbols, such as three-port valve, five-port valve, push-button operation, single-acting cylinder and double-acting cylinder.

Pneumatic symbols

Remember that any of the valve operators (for example, push-button operation; plunger operation) can be used with the three-port valves or five-port valves. It is important to choose the one that matches the system requirements and add them to the top and bottom of the valve symbol.

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