Electric Actuators vs Pneumatic Actuators
As you know, actuators are “movers” that play a key role when it comes to moving and controlling mechanisms in various industrial applications, including conveyors. Actuators work by drawing energy from some sort of source, and, as you might imagine, there are various types of actuators that typically differ based on where they derive their energy from. Two of the most common types of actuators found in industrial applications are pneumatic and electric. (Hydraulic actuators are also fairly common, but that’s a discussion for another post.) In this post, we’ll size each of them up and discuss the key differences between the two so that you can make the best decision for your application. Here’s a closer look:
Key Differences Between Electric and Pneumatic Actuators
The first big difference between electric and pneumatic actuators is where they draw their power from. Fitting to the name, electric actuators run on electricity, while pneumatic actuators run on air pressure. So first and foremost, it’s important to consider the power source, availability of such, and preferences when making your decision. Electric actuators typically require at least a 24 VDC power source, while pneumatic actuators rely on air pressure from a compressor.
Aside from power source, there are several other key differences that are worth noting between electric and pneumatic actuators. Here’s a closer look at some of them:
Speed
Pneumatic actuators operate through manual controls and at a constant speed.
Electric actuators use a program controller to instantly adjust the speed so it can be accelerated and decelerated while the device is in motion.
Cost
Pneumatic actuators are generally cheap. However, while component costs can be low, maintenance and repair costs can be significant and add up over time. Furthermore, it’s often costly to run a compressed air system to adequately power the pneumatic actuators, something else that needs to be considered when deciding between pneumatic and electric. While component costs for electric actuators are higher than those of their pneumatic counterparts, one significant advantage to electric actuators is that they’re much more affordable to power. While the upfront cost of the electric actuators is more than pneumatic actuators, there’s likely to be long-term savings in operating costs.
Temperature Range
Pneumatic actuators typically excel in a wide range of temperatures. In fact, they can adequately handle a range of between -40 and 175 degrees Fahrenheit, and special bearings and seals can help them operate sufficiently over an even greater temperature range. Electric actuators can operate over a wide temperature range as well (-40 to 150 degrees Fahrenheit), however, there’s more of a worry about overheating when actuators are powered electrically. Furthermore, operators also have to be mindful that any electric actuators are properly sealed so that they don’t become subjected to moisture.
Accuracy
While pneumatic actuators are known for providing high force at fast speeds, they often lack accuracy — at least compared to electric actuators. (Since air is compressible, they have very little positioning accuracy, they should really only be used for 2 position applications) In fact, an electric linear actuator is highly regarded for its precision when it comes to both control and positioning. These actuators help machine adaptability to flexible processes while at lower operation costs since the electronics are separated from the actuator, which helps to minimize costs towards replacement parts.
Electric actuators have positional accuracy down to .0001 inches.
Safety
Electrical actuators can be more safe and predictable in an emergency stop application since they don’t depend on trapped air to hold the cylinder in place. The load can be held more reliably also since there is no air leakage between the cylinder and valve. Electrical actuators will automatically shut off when experiencing an electrical short or when overheating.
When to Choose an Electric Actuator
Think about the advantages of electric actuators, and it’s relatively easy to see whether or not they’d be a good fit in your application. Here’s a look at some situations when it might make sense to select one:
- If you need precise movement and advanced integration.
- If it makes more sense to run actuators off of electricity rather than create a detailed air compression system.
- If there isn’t a high risk of moisture intrusion that could potentially damage the actuators.
- Though we didn’t mention it in the above section, it’s worth noting that electric actuators run much more quietly than pneumatic ones, which may also be a consideration during the selection process.
When to Choose a Pneumatic Actuator
Similar to selecting an electric actuator, look for applications that play into the advantages of pneumatic actuators. Some considerations on when to deploy pneumatic actuators include:
- In hazardous environments where electric actuators may pose more of a safety risk or have to comply with NEMA standards.
- In small-scale applications where performance can be optimized without driving up operating costs.
- If you’re looking for high force and fast speeds.
- If you need actuators to operate well over a wide temperature range.
Contact Us Today
For more information on pneumatic actuators vs. electric actuators and to get a better idea of which type would work best for your application in your industrial environment, contact JHFOSTER today. We’re standing by and ready to advise you on the best actuators based on your situation. Contact us today.