Deciding whether to use a pneumatic or electric valve actuator is a bit like finding a long-term partner. You need to take your time to carefully pick what will work out after the honeymoon phase is a distant memory. If you don’t, you could encounter some major bumps in the road ahead which could cost you time and thousands of dollars.
Sadly the choice isn’t always an obvious one. Making the right decision involves an evaluation of performance, component costs, system costs, and productivity gains as well as a good understanding of the advantages and disadvantages of each type of actuator.
Electric actuators are better known for their high levels of precision but this doesn’t mean that pneumatic actuators cannot deliver very precise motion. The issue revolves around how much precision you really need.
You also need to think about dependability and enduring productivity, especially for applications in unforgiving environments. Are the components man enough to work long periods without failing?
Starting with some positives, pneumatic actuators provide high force and speed at low unit cost in a small footprint. But there are shortcomings and these include operative expenditures, system maintenance and controllability.
Compressed air is not free and the energy it takes to compress air and move it through a plant is becoming a factor. Dealing with connection leaks, keeping air clean and dry and friction losses, can become time consuming and costly in both down time and maintenance hours.
Pneumatic control stays a respectable choice when promptness, simplicity, and established technology are essential. In addition, pneumatic actuators have adequate to high load capability at great speeds making them very desirable in many open/close applications
In contrast to pneumatics, electric actuators provide precise control and positioning, help adapt machines to flexible processes and have low operating cost. They are most economical when deployed in a moderate scale in processes where their performance advantages can be a benefit and when the electronics are separate from the actuator to segment and minimize replacement costs.
Electrically actuated systems are commonly used in automation applications because they are simple to interface with electrical control systems. In an electrically powered automation solution, the actuator and the controller are driven from the same power source, making installation simpler for the end user.
Electric actuators are more expensive up-front per unit which can put purchasers off but it’s important to note that the real cost savings will be seen in reduced down time and less maintenance a year or two down the road.