What is a Valve Actuator?

A valve actuator is a mechanical device that uses a power source to operate a valve. This power source can be electric, pneumatic (compressed air), or hydraulic (the flow of oil). There are two main types of actuators, one for each of the two main types of valves that require them. They are rotary and linear.

Selection of the best actuators type for any application is dependent on many factors including:

• Valve type

• Power sources available

• Environment of installation

• Operational functions and characteristics

• need for fail safe

• cycle life

• duty cycle

• speed of actuation

• need for manual override

• And as always... Cost

What Does An Actuator Do?

A valve actuator is the device that “actuates”—or moves—a valve open or closed.

It attaches to and works in conjunction with two parts: the valve body and the valve pilot.

What Are The Common Valve Actuator Types?

Two common types of valve actuator in upstream oil and gas operation are pneumatic and electric.  

Valve Actuator Standards, Testing & Course

Various ISA Standard & ISO Standards for valve actuators include:

• Sizing, Selecting, and Applying Process Control Valve

• Valve Actuator Testing

• ISA96.01 -requirements for terminology for valve actuator and their accessories

• ISA96.02 – requirements for electric valve actuator for both on-off duty and modulating applications

• ISA96.03 – requirements for pneumatic valve actuator of the single- and double-acting types used for on-off applications

• ISA96.04 – requirements for hydraulic valve actuator of the single- and double-acting types used for on-off and modulating applications

ISA96.05 – automated valve includes the following:

• Limit switches and other monitoring devices

• Air regulation and filtration system

• ISO 22153:2020 – requirements for electric valve actuator, used for on-off and control valves. It includes guidelines for classification, design, enclosure and corrosion protection, and methods for conformity assessment.