If you work in a sensitive industry, like food/beverage and pharmaceuticals, an oil-free piston compressor is likely the right choice. Since compressors generate a lot of heat, they require a cooling element to keep everything running.
With oil-injected air compressors, oil is used as a lubricant for the moving parts. This approach ensures minimal noise and heat from rapidly rotating components. While suitable for most applications, they leave traces of oil in the airflow.
Although it's possible to remove unwanted contaminants with filters and dryers, you'll want an oil free air compressor for optimal purity levels. Without the presence of oil, this equipment uses alternative methods to keep your equipment cool.
One reason these machines are less popular is due to size and output limitations. They are usually smaller, and aren't designed for heavy-duty applications. That being said, they're also cheaper and are relatively easier to move around.
When shopping around for air compressors, you'll likely encounter International Organization for Standardization (ISO) air purity classes. Starting from 0, they provide guidelines for acceptable contaminants in your compressed air.
Each industry has its own ISO recommendations, and, as mentioned above, industries including food/beverage and medical / pharmaceutical tend to be the strictest. The only way to achieve Class 0 air purity for oil is with an oil-free machine.
ISO Class 0 is the cleanest choice and means 100% oil-free. With this, you can guarantee optimal conditions for your end users, and avoid quality control issues. With this in mind, it's always best to seek expert advice when shopping for oil-free and oil-injected air compressors.
As a reference, Class 1 specifies an oil concentration of 0.01 mg/m3 at 1 BAR(A) 14.5psia and 20C (68F). This level is sometimes referred to as a "technically oil-free solution." Be careful of this term, as it's not the same as Class 0, and still includes undesired particles.
We offer a reliable oil-free piston compressor, the Mark CNR 75-100. It comes in 7-10 hp and 4-10 BAR models, which is suitable for the industries mentioned. In addition, this machine comes with high reliability and continuous operation.
It also comes with the Airlogic2T touchscreen controller for complete control and monitoring. This device provides remote insight on service status, running conditions, and potential maintenance and downtime issues.
You'll also find optimal energy efficiency with a direct drive motor and start-stop technology. Regarding air quality, the pump is Class 0 certified, and there's a built-in filter. It's specifically designed for generating clean, dependable compressed air.
In addition to using an oil-free compressor, you'll likely need a dryer to maintain an optimal pressure dew point (PDP). When evaluating your needs for your application, you'll want to pay attention to PDP (as well as ISO Class).
To achieve ideal PDP levels for the industries mentioned, a desiccant dryer is recommended. This equipment is able to achieve levels from -40C and lower. These dryers produce extremely clean, dry air for high-quality industrial production.
These machines work by pulling out water vapor with hygroscopic material like silica gel. When working with air compressors, removing moisture is important to avoid microorganisms, rusts, and other unwanted maintenance issues.
Alternatively, there's refrigerant or "fridge" dryers. These machines work by cooling down hot air, similar to how air conditioners operate. While suitable for 95% of applications, they're not ideal for food / beverage, medical / pharmaceutical, and other delicate industries.
We hope this guide provides a good overview of when it's useful to invest in an oil free piston air compressor. In addition to covering the basics of these machines, it was our intention to provide an overview of everything related to clean air quality.
If you require more information or further insight on the best solution for your needs, feel free to reach out. Our team is available to help.