Pneumatic rotary actuators are commonly used to convert compressed air pressure into an oscillating rotary motion. Like other pneumatic components, they are durable, offer simplicity and high force for their size, and can operate in hazardous environments.

There are two main types of pneumatic rotary actuators: rack and pinion, and vane – both are available in either single or double actuation:

Rack and pinion rotary actuators use a cylinder piston attached to a rack gear. 

When actuated, the piston and rack move in a linear fashion rotating the pinion gear and output shaft. 

A double rack unit utilizes two racks on opposite sides of the pinion gear, in effect, doubling the output torque of the unit.