A pneumatic system is where compressed air or gas is used to drive or power to do things like operate valves.In other words compressed gas used as a working force.
Why pneumatic system
Pneumatic system replaces electric motors and actuators. Say you need to control a valve remotely, a servo motor with actuator will do this function. For large number if component the number of motor and actuator will increased. But with pneumatic system, a single compressor will maintain the line pressure and this pressure can be used at any extent.
Pneumatic system:A centrally located and electrically powered compressor that powers cylinders and other pneumatic devices through solenoid valves can often provide motive power in a cheaper, safer, more flexible, and more reliable way than a large number of electric motors and actuators.(wikipedia)
how a pneumatic system works
Compressor,air pipe and solenoid arrangement is used in a simple pneumatic system.Say in a automation system a certain high capacity steam valve is to operate.Its purpose is to provide steam to heat.The force of compressed air or inert gas is used to operate this valve.
For a suitable application Pneumatic system might be replace with hydraulics system.
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