There are multiple factors to consider when choosing your air compressor and deciding whether an oil free compressor is suitable for your intended application!

In short, oil free compressors aren’t always as economical as an oil-injected or lubricated option. Still, they can be crucial where there is a need to reduce any risk of oil contamination.

Oil free compressors are often used in manufacturing techniques where air purity is imperative and ensures that delicate products or sensitive materials remain oil-free.

Let’s explore this further and explain the factors and applications best suited to oil free compressors and more conventional lubricated options.


How to Choose Between Oil Lubricated and Oil Free Compressors?

If you’re considering an oil free compressor, it’s likely related to a more refined or specialist application than a typical manufacturing process.

The majority of air compressors are lubricated with oil, which seals air in the components and smoothes their functions. 

Interestingly, an oil free compressor isn’t always technically oil-free and still uses oil in the compression chamber. However, the significant difference is that the compressor uses an intercooler rather than oil to maintain heat levels.

You’ll still find oil in an oil free compressor but restricted to lubricating the cylinder to safeguard the pump when in use.

What are the Benefits of Using an Oil Free Compressor?

When deciding whether you need an oil free compressor, the all-important consideration is to think about the application it is required for – rather than the broader process.

There are lots of benefits to opting for an oil free compressor:

An Oil Free Compressor Won’t Contaminate the Air

Perhaps the most critical functionality of an oil free compressor is that it maintains the environment’s integrity.

Some of the industries where this is necessary include:

  • Food and drink production.
  • Medicinal manufacture or pharmaceuticals.
  • Electronics production.

You can use a filter with an oil-lubricated air compressor, but given that this can’t always guarantee 100% air purity, an oil-free system is usually preferable. 

There are also different standards relating to oil free compressors, and we’ll explore the alternative air purity classes shortly!

Maintenance is Easier on an Oil Free Compressor

A plus point to an oil free compressor is that you aren’t going to have to deal with regular oil changes – and the inevitable maintenance requirements that go alongside.

These compressors have less moving parts and significantly less oil, and so there are fewer potential problem areas and less likelihood that you’re going to need replacement parts or services.

Of course, regular maintenance checks and servicing are always required to ensure any air compressor remains in excellent condition, but the cost burden is typically lower.

When is an Oil-Lubricated Compressor a Better Option?

There are some environments where an oil-lubricated air compressor is probably a more practical choice:

  • Industrial facilities.
  • High volume manufacturing.
  • Compressors used for more hours at a time.

A lubricated compressor can last longer and be more durable. In contrast, an oil-free alternative has a lower capacity and so provides less usage per compressor.

Oil-lubricated compressors can be quieter and maintain a cooler temperature. 

That happens because the oil draws heat from the compression process. Therefore, an oil free compressor can provide more significant heat and louder noise.

It’s essential to weigh up the pros and cons to ensure you’re choosing the right equipment for your application!

How Do Air Purity Classes Impact the Requirements for an Oil Free Compressor?

Oil free compressors are widely used in manufacture and production where air purity is a crucial requirement. That could include paper production, manufacturing semiconductors, or producing medications, for example.

In these situations, oil traces can be a severe issue, although a lot depends on the air purity class, dictated by the ISO standards for compressed air.

These standards assess how clean air is following compression.

  • ISO Class 1: Technically oil free compressors mean that while the solution is technically oil-free, there can be small concentrations of oil content in the vapour.
  • ISO Class 0: Oil-Free air compressors are 100% oil-free, producing clean air, and ideal for sensitive product manufacture or equipment which must remain free of oil contaminants.

If you require an oil free compressor, and air purity is a fundamental requirement, we’d therefore recommend opting for a compressor to ISO Class 0 specifications.

While the price point may be slightly higher, there are core benefits in safe usage and the guarantee that any manufacturing processes will remain completely free of any risk of oil contamination.


Contact AMS Processors for your air compressor maintenance or air compressor repairs.