Air motors harness the power of compressed air to generate torque and rotational motion in applications ranging from powering production machinery and rotating turntables to operating mixers and actuating valves. They’re often an engineer’s “go-to” solution for jobs an electric motor can’t handle. That’s because in many instances, air motors outperform their electric counterparts.
Advantages of air
One big advantage is safety. Because they do not require electricity and have no sparking hazards, air motors can be used in volatile atmospheres. Explosion-proof electric motors, on the other hand, require costly special housings. Air motors can also be overloaded and stalled without harm. Overloading an electric motor, however, can trip circuit breakers and damage the motor.
By their nature, air motors tolerate adverse environments well. Dust and dirt that can shorten the life of electric motors has little effect on air motors, provided the air supply sees proper filtration. Likewise, air motors withstand wet, humid, and aggressive washdown conditions. High temperatures also tend to limit the performance of electric motors. Air motors, however, are self cooling and generally perform well to 300°F and, in some cases, even higher. Cool-running air motors can also be a better choice in applications with frequent starts and stops, because electric motors must be greatly oversized to dissipate heat generated by high starting torque.
Air motors generally have a higher power density than electric motors, so they can transmit more power from the same envelope or the same power from a smaller envelope. This is especially true when loads must be driven at less than the nominal speed of the electric motor — which necessitates using an electric gearmotor or separate gear box.