How Do Electric Valve Actuators Work?
Electric valve actuators control the opening and closing of valves. They can provide linear or rotary motion and work with different types of valves, including ball and butterfly valves.
Electric valve actuators respond to prompts via remote control or centralized process control systems, making them invaluable for managing systems that are difficult to reach or spread over large areas. Process control systems can operate electric actuators from a centralized system to provide predetermined and programmed commands, enabling organizations to automate systems and increase reliability.
Overall, electric valve actuators are becoming more sensitive, technologically advanced, and easier to use. The following guides explain what you need to know about how these components work and what you need to install and use them.
Electric Actuator Components
Unlike other valve actuators, electric actuators contain a motor that converts electrical energy into linear or rotary motion to open, close or regulate the corresponding valve. Different electric actuators control different types of motion; for example, a quarter-turn actuator will turn the valve train 90 degrees, i.e. fully open.
It is important to select an electric valve actuator that operates at the correct voltage to match your facility's systems. These systems differ depending on whether the operator is using alternating current (AC) or direct current (DC) power.
Some of the most popular voltage types are:
In addition to the motor, an actuator has other electrical components including limit switches, wiring, and gearing. All these components are arranged in a compact protective housing unit.
Torque Requirements for Electric Valve Actuators
Torque is the rotational force developed by an actuator to close a rotary valve. Electric actuators can generate this force by transmitting it to the output shaft and then to the valve stem. The orifice of the valve opens or closes when pressure is applied to the stem.
Actuators have different levels of motor capacity (power) depending on the torque the actuator needs to provide. It is important to select the actuator according to the breakaway torque required by the valve. "Breakaway torque" is the power required to start a switch from a static open to a closed position or vice versa. This is the highest torque level required to operate the system.
When installing an electric valve actuator in place, use sturdy industry-standard parts. Many actuators and mounting hardware are connected using the ISO 5211 standard, ensuring that various brands and components work together seamlessly.
You need at least three components to install:
The valve stem connected to the valve head
Flange to mount the actuator to the valve
Various actuators require different types of flanges depending on available torque and fasteners.
How to Choose an Electric Valve Actuator?
Electric valve actuators can make fluid systems safer and easier to control. They are especially useful if you need to expand or upgrade your system and make it more complex.
Here are some parameters to help guide your decision:
Torque: Consider the general torque and breakaway torque requirements of the system. Secondary factors affecting torque include fluid viscosity and valve size.
Voltage Requirements: Determine the current type and strength of the actuator installation site power supply.
Valve Installation and Connection: Different flanges, actuators, and installation environment requirements will limit your choice of electric valve actuators.
IP Rating: IP ratings are determined by IEC 60529 and provide varying levels of protection against environmental elements such as moisture and dust.
Enclosure Protection Certification: Likewise, protective enclosures and enclosures must be able to act as a barrier against the application hazards of the specific environment.
Failsafe: The integrated electric valve actuator can be programmed with automatic settings that take effect in the event of a power outage, emergency, or system failure.
Modulation: Some actuators can control fluid flow rate, modulating it, while others only allow on/off control.
Application: Fluid material, temperature, and other factors of the intended application can also affect the optimum operation of an electric actuator valve.
Applications of Electric Actuators
Electric valve actuators serve a variety of industries. These industries include:
Food and Beverage
Oil and gas
The above briefly introduces some common problems of electric actuators. If you want to buy electric actuators, please contact us.
UG Controls is a professional custom valve actuator manufacturer. We use our engineering expertise and industry experience to continuously improve our products, striving to provide efficient solutions and competitive prices. UG is also a global supplier of highly engineered actuators and accessories to the Oil & Gas, Mining, Chemical, Pharmaceutical, Water & Power, Food & Beverage, and general industrial markets.