Here are some examples of different types of actuators in action: 1. A #pneumatic actuator works by receiving a signal of air pressure through a top port. This pressure pushes down on a diaphragm plate, causing the valve stem to move and control the valve. 2. An #electrical actuator, like the one operating a butterfly valve, uses a motor to open or close the valve. 3. In a #hydraulic actuator, such as the one on a dump truck, hydraulic pressure extends to lift the box. | RealPars