Piston compressor or reciprocating compressors and rotary screw air compressors are two of the most popular compressor technologies available today. But do you know which one would be better suited for your specific needs and applications? Understanding the difference between piston and rotary screw air compressors and the capabilities of each technology is key. That’s why we’re covering the basics below!
Should I Choose a Screw or Piston air Compressor?
The main difference between a screw and piston (reciprocating) compressor is the way they compress the air. Screw air compressors use two meshing helical screws, while piston air compressors use pistons driven by a crankshaft. Another difference is the moving parts as the screw compressor has two moving parts which are not in contact while the piston compressor has a lot of moving parts. The screw compressors operate at a lower temperature and integrate a good cooling system.
What Factors Should I Consider?
Initial and operating costs, energy efficiency, duty cycle, and service intervals are important factors to consider when determining whether your business will benefit most from a piston or a rotary screw compressor. Noise levels is an additional factor to take into consideration.
- Initial Cost vs. Operating Costs. Budgeting for a compressor shouldn’t only include how much you pay for your compressor upfront; you also need to consider how much you’ll pay for your compressor in the long run (i.e. your overall operating costs). As much as 70-75% of a compressor’s lifetime operating costs are spent on energy usage, so keep that in mind when selecting a compressor technology. Pistons have a lower initial cost than screws, but screws cost much less to operate over time.
- Energy Efficiency. If both a piston and a screw were running the same amount of hours, the screw compressor will be much more efficient and have lower operating costs than the piston over the lifetime of the compressor. When selecting a technology, ask yourself: Is the initial or lifetime cost more important to you and your business?
- Duty Cycle. Because piston compressors are limited in their duty cycles, they’re ideal for applications with low duty cycle requirements and low daily running hours. Screw compressors, however, have long duty cycles. In fact, screws are engineered to run 100%, all day, every day!
- Service Intervals. There are more moving parts in a piston compressor than in a screw, which results in increased machine wear and tear. Screw compressors don’t have as much wear; hence, they have reduced maintenance needs. But keep in mind that it’s important to keep any type of compressor on a consistent maintenance schedule! This will help ensure machine efficiency and optimal system performance.
- Noise Levels. Piston compressors are loud – especially in comparison to screw technology. If you’re looking for a lower-noise machine or a low noise level is required, you may want to consider a screw compressor.
In brief
Piston compressor a great option as an entry level compressor, but it's common for facilities outgrow the unit. If you need a consistent and or increased flow (CFM) and are looking for something that is compact, efficient, reliable and quiet, going with a rotary screw would be a great option. It’s quite normal for a company to start out with limited need for compressed air, but as production and customer demand increases, so does the need for increased output and the need for a larger compressor that can adequately handle the demand and increased duty cycle!
Still struggling with which technology is right for you? Our compressed air experts are always available to talk you through the decision! Give us a call or email us
