Choosing the Right Actuator
Choosing the right actuator is very important. Even if a valve has an intrinsically equal percentage characteristic this can be negated through a poor choice of actuator. For example, if the stroke of the actuator does not match the stroke of the valve then the characteristic may be deformed. This is particularly important when the stroke of the valve is being changed in order to regulate the maximum flow rate of the valve.
If the valve has an inherently linear or on/off characteristic then this can be improved in some cases by using a characterising actuator to change the intrinsic curve to a more acceptable one. However, it is important to match the characterising action of the actuator to the valve to which it is fitted.