When it comes to designing a motion-enabled machine, engineers often have to decide between different types of actuators. Two of the most common actuators available are Electric and Pneumatic.
A linear actuator is a fairly common device that is capable of moving a load in a straight line. It converts energy into mechanical movement to achieve some purpose.
That said, engineers developing new machines and processes need to consider a wide range of variables when deciding which device will best suit their purpose.
Linear actuators are available in dozens of different styles and choosing which to use in a project is no easy task. Pneumatic and electric actuator systems are very different and one can not easily be replaced with the other. Of course, each technology has it's advantages and disadvantages. That's what we're going to cover in this post.
Should you use electric or pneumatic actuators in your industrial application? It can be a complicated decision to make, as they're functionally similar, but have some key differences.Pneumatic Linear Actuators
Pneumatic actuators are cylinders that are driven by compressed air. They are best suited to applications that require a high force and speed with a defined stroke. The pros and cons of pneumatic linear actuators include:
Advantages
- Tend to be inexpensive when compared to other actuator systems
- Great for large systems with many actuators. Typically with pneumatic systems, the more actuators in the system, the lower the cost per unit to both implement and maintain
- High force and small size
Disadvantages
- Not ideal for applications that require different stroke lengths at different times. They tend to operate from end of stroke to end of stroke
- Not ideal for applications where precision positioning is required
- Air lines that are required to run a pneumatic system tend to make the system less reliable.
Screw Drive Electric Actuators
A screw drive actuator takes the rotational force of an electric motor (brushed, stepper or AC) and converts it to linear motion by driving a nut in and out along a threaded screw. Usually this is through a gearbox to allow customization of the power/speed ratio.
Electric linear actuators are best suited to applications where precise positioning, unit customization or a wide range of control options is required. They tend to have a lower cost for small-scale operations as it's not necessary to run a compressor and air lines.
Advantages
- Different motor options available depending on your needs. Brushed DC actuators are powerful and fairly accurate whereas stepper motors have less force, but operate with higher precision
- Lower cost of implementation
- Lower maintenance than pneumatic systems as there are no air lines to rupture
- Wide range of control options
Disadvantages
- Electric actuators have more components within the device, and can have a higher unit cost than pneumatic
- Not always ideal for very high speed applications
- Tradeoff between speed and force
When comparing the benefits of electric vs. pneumatic actuators, it's important to look at the component costs and life expectancy of each system. While the initial cost of electric actuators can be higher due to their modular design, maintenance and other operational costs associated with pneumatic systems tend to be considerably higher. There's also the downtime and hassle associated with identifying and repair air leaks in a complex pneumatic system. We believe that for most small-mid-size operations, installing electric actuators can result in considerably lower costs over time.
If you would like to some help choosing which type of system is right for your project, give our experienced sales team a call or email, they will be happy to assist you.
Electric Actuator FAQ
Can electric actuators be customized to meet specific requirements?
Yes, an electric actuator manufacturer can work with you to develop a custom electric actuator. Many aspects of an actuator can be customized including stroke, force, input, limit switch position, mounting method, motor voltage and more. For more information on custom electric actuators, check out this page.
What types of motors do electric actuators use?
Electric actuators use one of three motor types: DC, AC or stepper motors.
Can I adjust the speed of an electric actuator?
Yes. How to adjust the speed of an actuator depends on the motor and input on the specific device, but it is possible. For more info on adjusting actuator speed, check out this article.
What is needed to control an electric linear actuator?
This depends on the actuator. DC motor actuators can be controlled with a simple rocker switch. Servo actuators require an Arduino, RC receiver or other device capable of outputting a standard servo signal. See the data sheet for the specific device you’re considering for details on how to control it.
What is the duty cycle of an electric actuator
This depends on the actuator, but you can expect duty cycles for DC actuators to start at 20%. Stepper actuators have duty cycles up to 100%. Always check the datasheet for your specific actuator and choose one that is appropriate for your required duty cycle.
Now You Understand the Differences Between Electric and Pneumatic Actuators
Choosing an actuator system is a major consideration. We hope this article has helped you better understand the differences between the two systems as well as the advantages and disadvantages of each. If you have further questions about Actuonix Motion Devices products, you can reach out to our sales team anytime!
As Actuonix and the industry navigate the complexities of electric actuators, we witness how their simplicity and reliability contribute to powering the machinery that defines our modern world.