Valves are components used to control the flow of fluids in various industries, preventing backflow, overflow, and leakage. There are different types of valves designed for specific functions, and each type plays a crucial role depending on the application.

However, closing and opening or operating valves manually can be a slow process and create a hassle, and sometimes, it can be dangerous when you need to quickly shut off the valves in the chemical, power generation, and petroleum industries. 

Hazardous gases or fluids can be leaked during manual operation, posing risks to humans, animals, and the environment.

These problems are overcome by valve actuators, which provide an automation process to control the valves, ensuring safe, efficient, and precise fluid regulation. 

In this article, you can get a better idea of the types of valve actuators and their applications and working processes. But before that, let’s understand what valve actuators are.

What Is A Valve Actuator?

Valve actuators help to operate the valves automatically with the help of power sources, such as electricity, compressed air, and hydraulic energy. It helps industries such as food plants, nuclear power plants, wastewater treatment, and more, where manual operation is not possible for better fluid regulation.

Working Principle Of Valve Actuator

Valve actuators are connected to a control system that sends signals to tell them when to open or close the valve. The valve actuator works with a power source and contains a motor, gears, switches, and a control circuit.

When the energy supply is given to the actuator, it converts the signals into mechanical energy that helps to rotate the motor. This motion can be either linear (moving in a straight line) or rotary (rotating), depending on the valve design.

When the motor rotates, the connected valve stem also moves accordingly, which helps rotate the disc or ball. After this process, the fluids started to flow through it.

Actuators also regulate the signal to the control circuit to show the position of the disc with the flow rate. It helps with the real-time monitoring and automation of the system.

Valve Actuator Operation

1. Linear Operation Actuators

Linear operation actuators are designed to provide a straight-line motion by converting rotational motion into linear movement. It helps to move substances with push or pull (forward and backward) motion along an axis. 

Among linear actuators, electric linear actuators are the best for achieving precise and controlled repeated motion. 

Linear actuators are low-maintenance, easy to install, and sustainable in all environmental conditions. Due to its versatile performance, it is used in industrial machinery and home automation applications.

2. Rotary Operation Actuators

The rotary operation actuators are a completely mechanical operation that produces a torque, rotation, or oscillatory motion. It converts electrical, pneumatic, or hydraulic energy into mechanical energy. 

These actuators are used for both manual and automatic valves. It differs from the linear actuators, which develop a linear motion against the rotary motion. Meanwhile, rotary actuators can work as linear actuators when additional equipment is connected.

Rotary valve actuators are mainly used to generate rotary or angular motion. It is used in medical equipment, radar and monitoring systems, robotics, and defense.

Types Of Actuators

1. Manual Valve Actuator

Manual actuators do not need any external source or energy to move the valve. They are manually operated using a handle lever, a chainwheel, or a declutchable mechanism that rotates the valve’s disc to a desired position with the help of the setup of gears. 

For higher torque generation, it uses a handwheel. The slower cycle time of manual actuators helps reduce the risk of water hammering, a phenomenon caused by sudden changes in fluid flow.

These actuators are cost-effective, low-maintenance, and reliable.

Applications

• Bulk pipeline isolation to fluid flow and efficient regulation. 
• Residential and commercial plumbing to control the liquids.
• In low-pressure systems, such as water transportation pipelines.

2. Electric Valve Actuator

The electric actuator is a quarter-run (90-degree) rotation valve actuator. It consists of an electric motor that generates the torque to rotate the stem of the valve with the help of gears. 

The disc or the ball rotates and opens a gap between the disc or valve and the valve sheet. After the orifices open, allow the fluid to flow. 

Electric actuators are mainly of two types.

• Electromagnetic actuators
• Piezoelectric actuators

Applications

• Industrial automation for precise welding techniques
• Used in irrigation to distribute the water, adjust the flow control, and regulate the pressure.
• Water supply controls the flow of water.
• Heating systems to control the temperature or cooling liquid flow
• Fluid transportation or transfer in the oil and gas industry.

3. Pneumatic Valve Actuator

A pneumatic actuator is used to convert compressed gas into energy. In this actuator, air enters a chamber and is stored in a compressed form. 

When the compressed air creates more pressure than atmospheric pressure, the air changes into kinetic energy and puts pressure on the gears or pistons. As a result, the valve moves in a linear or rotary motion according to the design. 

It is commonly used in most industries to convert compressed gas into kinetic energy. It is a controlled, reliable, and repeatable actuator.

Applications

• In the automobile, it is used to control the engine, transmission, and braking systems
• Material handling for pick-and-place operations.
• Food and beverage production uses conveyor systems to move products from one place to another.

4. Hydraulic Valve Actuator

A hydraulic actuator is a cylindrical-shaped actuator. It is operated by fluid pressure and generates a linear, rotary, or oscillatory motion. It consists of various mechanical tools, such as balers, cranes, excavators, loaders, and presses.

The hydraulic valve actuator uses a large force when the fluid cannot be compressed much further. The generated pressure puts force on the diaphragm of the valve, which helps move the piston and open or close the valve.

Applications.

• Used in crane drives, wheel motors in military vehicles, feeder drives, and agitator drives
• Used in a hydraulic jack to lift heavy equipment.
• Controlling closed-loop velocity to control fluid velocity.

SMART CENTRALIZED WIRELESS VALVE CONTROLLER (An Automatic Butterfly Valve Actuator)

The Smart Centralized Wireless Valve Controller is an automated butterfly valve with a control system and an actuator. The IoT-enabled, Wi-Fi-operated butterfly valve can be controlled both manually and automatically. The smart actuator can control this valve remotely via a web application.

To function, the valve requires a 220-volt AC electric supply.

It contains an IP67-enclosed actuator unit and an LED for status monitoring to check the position of the valve and process control. This smart valve controller is designed for versatility, making it suitable for applications across a wide range of pressures and temperatures. Whether in industrial or domestic setups, it provides efficient, reliable control.

Conclusion

Actuators help with valve automation at remote locations, which is a hassle-free process. However, selecting an actuator for the valve is a confusing task. Some factors affect the valve actuators, such as response timing, control valve operation, cost, compatibility with various fluids, and environment. These factors help you choose the best actuators for your applications.

You can take an expert’s suggestion before installation in your application.