A Brief Introduction to Pneumatic, Hydraulic, and Electrical Actuators

Are you planning to design an actuator-driven system? Perhaps, you will need the right actuator to support it. You can choose from pneumatic, hydraulic, and electric actuators. All these actuators help control the movement of a device. Well, before starting with a breakdown of these actuators, firstly it is important to understand what linear actuators are. A linear actuator is a mechanical device, which moves a product or a load in a straight line. The energy source that operates a linear actuator can be anything such as pneumatic, hydraulic or electric. The choice of hydraulic, electrical, and pneumatic actuators involve various factors such as costs of components and systems, desired performance, cost of operation, and productivity gained. These three actuators are designed for specific benefits, so they largely differ from each other, and cannot be a replacement for one another. Would you like to know what these specific advantages are? Are there any disadvantages, too? Read the post to know more.

Differentiating Between Pneumatic, Hydraulic, and Electrical Actuators

The following information will help you understand the difference between pneumatic, hydraulic, and electrical actuators.

1. Pneumatic Actuators: Pneumatic actuators are driven by air or gas, which is a clean operating medium. This medium helps prevent leakage or dripping, as in the case of many other actuators. Pneumatic actuators are known to convert compressed air into linear or rotary motion. The following advantages of these actuators have contributed to their popularity.Advantages:
   • The simple design of the actuator makes it popular, and perfect for application where cleanliness is a must.
   • There is a minimal risk of contamination from the power supply because these actuators are gas-driven.
   • These actuators feature no motors, which means no magnetic interference is created at high temperatures. This makes the actuator ideal for applications involving high temperatures.
   • These actuators require almost no maintenance, are lightweight, and equipped with durable components. All these help lower their costs of operation.
   • Pneumatic actuators are suited for applications, where regular closing and the opening is required.

   Disadvantages:

   • Compressibility and pressure losses are two factors that make these actuators imperfect for various key linear motion applications
   • At times, it is very difficult to achieve positional accuracy with these actuators, which is one of the largest drawbacks.
   • Noise generated by these actuators is large, which makes them incapable of applications where silence is required.
2. Hydraulic Actuators: These actuators also are known as hydraulic cylinders, and are designed for high force applications. These actuators convert the energy of the fluid into mechanical energy and are capable of producing forces 25 times greater than pneumatic actuators. These actuators are differentiated into three types – hydraulic linear actuators, rotary actuators, and semi-rotary actuators – depending on the motion produced by them. Hydraulic linear actuators help create motion in a straight line. These actuators are suited for applications where large forces or high speeds are required.
   Advantages:
   • These actuators offer high horsepower than the pneumatic actuators.
   • The small and compact construction of these actuators makes them perfect for many miniature devices of the day.

   Disadvantages:

   • In some cases, the fluid may leak that will lead to huge losses. More to this, these fluid leaks will also cause cleanliness problems, and damage their surrounding components.
   • These actuators require too many companion parts, such as heat exchangers, motors, pump and more. This increases user maintenance throughout the lifetime of the actuator.
   • Midstroke positioning is difficult to achieve with these actuators, and it requires lots of user support, as well as additional components.
3. Electrical Actuators:Electrical actuators are equipped with a motor. The rotational energy of the motor is converted into the linear movement of a device. This actuator possesses high positioning capabilities owing to electronic controllers fitted within. These capabilities along with velocity control are brilliantly exploited by various industries today. These actuators are easy to set up, and can be reprogrammed quickly, and offer an immediate response. Electric actuators offer a wide range of motion profiles, owing to their versatile designs.
   Advantages:
   • These actuators require almost no maintenance, except for the replacement of worn parts.
   • They do not leak fluids, so there are no cleanliness issues, also the environmental hazards are eliminated.

   Disadvantages:

   • The purchasing cost of these actuators is considerably high than the other two types, but their operating and maintenance costs are low.
   • They are not suitable for hazardous and flammable areas.

Thus, each of the aforementioned actuators offers a set of benefits and disadvantages, which may or may not suit your application. It is important that you source these actuators from a reliable manufacturer or a supplier. Venture Manufacturing Co. is one of the leading manufacturers of electric linear actuators. The company provides these actuators in various configurations.