Have a look at every industry, and you will find applications of automated valve actuators used everywhere. They are used in the mining, petrochemical, pharmaceutical, and oil & gas industries.
So what exactly is an actuator? Basically, it is the part of the mechanized system of pneumatics or hydraulics that offer a force for the movement in a precise manner.
Some differences between a hydraulic and electrical actuator, is that the electric actuator requires an amplifier that is usually mounted in a screw-mounted control cabinet, while hydraulic actuators require a single rod drive with a small number of screws and high power.
There are various types of valve actuators and manufacturers available in the market for valve automation; however, in this particular topic, we will compare two particular types of actuators:
- Hydraulic actuator
- Electro-hydraulic actuator
Hydraulic and electrical systems have their own advantages, but it can be assumed that hydraulic actuators are better suited for high-force applications. These are typically used for valve automation for either linear and rotary valves. A robust valve actuator can generate forces much higher than those of an electric hydraulic system, such as a hydraulic pump. Torque is kept constant by supplying the pump with more liquid pressure and using incompressible liquids.
Hydraulic actuators use fluids for the movement of the objects in a certain direction. These are the most authentic source of actuators to be used for energy conversion. Due to the amount of pressure used, these actuators are considered ideal for the heavy-duty task, including military weapons, construction, propulsion, and transportation.
Hydraulic actuators offer magnificent horsepower to weight ratio. Due to the use of fluids in their system, these valve actuators offer a tremendous amount of power and thus prove economical and efficient for heavy-duty tasks.
- Greater control:
These valve actuators offer great control and, thus, highly dependable when it comes to safety and security.
Hydraulic actuators also offer mobility. These systems are well-contained and require no complicated system along with them.
An Electro-hydraulic actuator drives energy from the alternating current and convert this energy into torque to derive the actuator. Electro-hydraulic actuators can also consist of a mechanical feedback mechanism in which mechanical feedback forces can be provided by generating mechanical “feedback forces” that compensate for the input forces of the load generator in order to create a more precise and reliable control system for the use of electro-hydraulic actuators.
Some of the advantages associated with valve control using electro-hydraulic actuators include the following;
Electro-hydraulic actuators are prompt performers. If you are looking for an actuator for a light yet fast task, electro-hydraulic actuators are the best choice.
These valve actuators offer greater precision as compared to other actuators available in the market. They do not exhibit tolerances like backlash, slack, and flex, similar to pneumatic and hydraulic actuators.
Electric power comes with zero leakage issue and thus offers a highly clean source of energy. With electric actuators, you do not have to worry about the leakage issues.
The two different technologies have a number of advantages in common, including the ability to hold a position during braking and better control of hydraulic cylinders. Electro-hydraulic actuators (EHA) offer additional advantages as they are completely self-sufficient and do not require hydraulic systems or infrastructure.