With a relatively straightforward composition, a piston air compressor is less complex than a rotary screw machine. Generally built with a piston, intake valve, and cylinders, this arrangement rapidly forces air through multiple stages. Driven by a crankshaft, the piston is powered, starting the compression process.
Given the simplicity of a piston compressor, they're relatively easy to maintain and are the most affordable option to buy. These points make this type of compressed air equipment the most popular. While seemingly an obvious choice for industrial, commercial, trade site, and home workshop related applications, piston compressors aren't a universal solution.
One of the biggest drawbacks of a piston compressor is their runtime limitations. If your application requires all-day air demand, you're likely better off getting a rotary screw air compressor. Read on below to learn more about ideal situations for using a piston air compressor.
Piston air compressor applications
In a related article, we cover the benefits of piston compressors for various applications. Where piston compressors shine is with their versatility, and, in some cases, portability. Unlike rotary screw air compressors, these machines come in portable models built for the outdoor elements.
Additionally, most piston compressors have a small physical footprint. Due to their minimal engine size, they can fit in fairly tiny spaces. Also, unlike rotary screw air compressors, these machines run on various power sources, including electricity, diesel, and petrol. These options add to their versatility and potential.
However, as mentioned above, where piston compressors fall flat is with their runtime limitations. Also, since the motor runs at one speed, they don't offer the same capabilities as a variable speed drive (VSD) rotary screw air compressor.
That being said, there are some options among piston air compressor models, including oil-injected and oil-free.
Oil-injected vs. oil-free
Since the drive train produces friction/heat from its various moving parts, cooling is necessary. The most common solution is using oil to reduce hot air, which is separated using a filter. However, for applications that require high air quality, this setup may not be the most ideal.
With this in mind, there are oil-free models which use an internal cooling fan. While they cost more than oil-injected compressors, these machines produce much cleaner air. They're also better for the environment since there's no potential for oil contamination. This is especially beneficial for food and medical applications.
If you'd like to learn more about this topic, read our article titled the right piston compressor.
Piston vs. rotary screw air compressor
Throughout this article, comparisons are made between piston and rotary screw air compressors. When purchasing any new equipment for your facility, it's important to evaluate all factors - beyond initial cost of investment. If that's your only requirement, a piston air compressor can be the best choice.
However, if you run a smart factory, operate equipment all day long, and work across various jobs, a rotary screw air compressor is superior. Since rotary screw models come with various drivetrain arrangements, there's more room for innovation, technology, and efficiency options. Although they cost more upfront than a piston air compressors, they're usually cheaper to operate.
The only thing a rotary screw machine doesn't offer is the portability from some piston compressors. If you work in a fixed location, it's worth considering a rotary screw model. In some instances, we recommend upgrading from a piston to a rotary screw setup.
If you'd like a more in-depth overview, we've created a guide on rotary screw air compressors. It's worth a read if you're undecided on the right option.
The best solution for you
We hope this guide provides a comprehensive overview as to how a piston compressor works, and their differences from rotary screw models. While it points out advantages of rotary screw equipment, there's still situations where a piston compressor shines.
In addition to offering a straightforward approach, these machines are easy to maintain. If your applications are consistent, and don't require all-day pressure, they make for a reliable solution.
Ultimately, we want to help you find the best solution. Our team is happy to evaluate your current setup and walk you through various options.
With our state-of-the art equipment and country related experts, you'll receive the best possible product for your industry. Feel free to get in touch with us today to get started.