What Does an Actuator Do? An Engineer’s Guide to Actuator Valves

You may have heard some of the arguments for using valve actuators in your pipeline system.

But what does an actuator do?

Using valve actuation can bring many benefits to your operation including reduced maintenance costs, increase uptime at your plant, and increased plant safety.

Keep reading to learn more about what valve actuators do and the different methods of valve actuation that you should be taking advantage of in your plant. 

What Does an Actuator Do?

The basic explanation is that actuators move your valves to a certain desired position by using an outside power source. There are different types of valve actuators, but they all are responsible for performing the following functions.

They must move the valve closure member to the position you want. The valve closure member is made of up the plug, disc, and ball. The actuator needs to create enough torque to move these things even under severe conditions. 

The actuator also needs to be able to hold the valve closure in the position you desire. This means it needs enough fluid power or spring to take on the dynamic torque that throttling applications create.

The actuator must seat the member with enough toque to ensure the shutoff specification. 

Actuators should also provide a solution in the event of system failure, like springs or battery power. Their fail positions can be either open or closed.

Your actuator needs to be regulated to provide enough operating speed and provide enough rotational travel.

Types of Actuators

There are various methods of actuation, but they all use a single power source. Let’s take a look at the most popular methods of actuation.


Manual actuators don’t require any outside power sources. Instead, they use a level or handwheel.

These drive a series of gears. This level can also serve as an indicator of the position of the valve.


These types of actuators use electric currents to control the gears needed to generate enough torque to adjust the valve position.


Pneumatic actuators work by converting air pressure into rotary or linear pressure in order to control the valve position


These types of valve actuators work by converting fluid pressure instead of air pressure. Fluid pressure is converted into rotary or linear motion and used to control the position of the valve. 

Choosing an Actuator

Hopefully, you now have a better understanding of the answer to the question. “What does an actuator do?” and a better idea of why using valve actuation is so important.

It’s also important to consider several factors in order to choose the right actuation method and size for your operation. You’ll want to take into consideration the type of valves you’re using, the power source you want to use, the operating environment, the failure mode specification, and more.

If you need help choosing the right type of actuator for your needs, we’re here to help. Contact us today!