Pneumatic actuator Pneumatic actuator A pneumatic control valve actuator converts energy (typically in the form of compressed air) into mechanical motion. The motion can be rotary or linear, depending on the type of actuator. A Pneumatic actuator mainly consists of a piston or a diaphragm which develops the motive power. It keeps the air in the upper portion of the cylinder, allowing air pressure to force the diaphragm or piston to move the valve stem or rotate the valve control element. Valves require little pressure to operate and usually double or "triple" the input force. The larger the size of the piston,
Potential energy positive work is a reduction in the potential, that is where "C" is the trajectory taken from A to B. Because the work done is independent of the path taken, then this expression is true for any trajectory, "C", from A to B. The function "U"(x) is called the potential energy associated with the applied force. Examples of forces that have potential energies are gravity and spring forces. In this section the relationship between work and potential energy is presented in more detail. The line integral that defines work along curve "C" takes a special form if the force F