We were recently on a tool forum where the question was asked ” what is the difference between oil-free and oil-lubricated air compressors?” This is a good question so we decided to post what we consider to be a thorough answer!
Oil-free compressors have pumps that are directly linked to the motor. A teflon-coated cylinder sleeve and piston ring result in very little friction between the Teflon parts, eliminating the need for oil. Some advantages of oil-free design are no messy oil spills, cleaner output air and no maintenance except for intake air filter. The teflon piston ring and cylinder are easily and economically replaceable resulting in extended compressor life. Oil-free compressors are also lighter in weight.
Oil-lubricated compressors have pumps that use an aluminum crankcase and head for improved heat dissipation, cast iron cylinder sleeves, and automotive style pistons and compression rings. Some advantages of the lubricated design include aluminum components that are noncorrosive, lightweight and improve heat dissipation. Of course, this pump does require oil and some maintenance. There you have it, now the choice is yours!
Appreciate the blog. One follow up. It feels like from the description that buying the oil free gives you the performance while avoding the hassle of the oil version. When and why would someone buy the oil version over the oil free? Thanks.
Great little sum up of the difference between oil-free and oil-lubricated.
Might I add that we would always recommend lubricated compressors. Yes they are a bit more messy (especially if its a little compressor and it falls over!) and require you to maintain the oil level. However they are far more reliable and not as noisy. We see a lot more oil-free compressors come in for repair than lubricated. So the extra effort in keeping it oiled is definatley worth it from our experience!
I hope that helps.
I appreciate the write up but wondering which would last longer? I have an oil free one at the moment and in the market for a new compressor. Seems the oil compressor would be more durable, no?
Oil compressor tend to last longer and are more heavy duty. They are hard to get working when it is cold outside.
Why are many oiless compressors able to render 135psi-200 psi for a lower cost than oil compressors dishing out mostly 125psi? I do realize
that 2 stage oil types are able to deliver 175psi.
Oiled vs. Oil-less Air Compressors
Air compressors draw air in with a piston. The air is then compressed into a storage tank. For maximum efficiency, the piston chamber needs adequate lubrication, for which oil is used. These are oil air compressors. However, in oil-free compressors, the cylinder is pre-lubricated (mostly with Teflon) for permanent lubrication. The Teflon coating protects the pump. That’s the major difference. While oil compressors need regular oiling, the latter doesn’t require any lubrication.
Oil-less compressor are low-maintenance devices that does not need oil for its running. Although these compressors are easily affordable because of low-expense but they have a low durability. Engines of such models are burned quickly, they are louder and their servicing is a bit difficult. Oil-free compressors are ideal for household use as they are cheaper and suitable for small applications.
investing in an oiled air compressor will be more feasible and satisfying in the long run due to its durability and also capacity for commercial use. Moreover, it will be never frustrating as the lubrication can be controlled by you, unlike in an oil-free model.
Oil Free compressors are less expensive, lighter in weight, produce as much air flow (CFM) & pressure (psi) as many oil lubricated models. However, they are loud & much less durable than an oil lubed cast iron pump. But they can be a good choice for the very occasional DIY or homeowner.