Air Line Lubricators – do you need them?

Air Line Lubricators
(Last Updated On: October 11, 2020)

An air line lubricator’s purpose is to deliver measured amounts of lubricating oil into the compressed air stream that’s flowing from the compressor to the application.

The end application, often an air tool or high speed air cylinder, requires an external source of lubricant to function properly due to the speed of the tool, or the absence of factory supplied internal lubrication.

Inside the air line lubricator drops of oil enter the air stream as it flows through the lubricator. The compressed air stream, at sonic velocity, atomizes the oil, and carrys it downstream from the lubricator to the tool or actuator.

Make sure that the distance from the lubricator to the end application is short (1-2 meters) as possible to ensure that the oil that’s being carried in the air actually reaches the tool.

Also, remember that the air from the lubricator ultimately exhausts to atmosphere through the air valve or the exhaust vent of the tool, and those in the area may actually end up breathing oil impregnated air.

Do yourself and your environment a favor. Make sure you actually need a lubricator before you plumb one into the air supply. Many air-driven applications are now supplied with factory installed “lubrication for life” and don’t need an external oil source at all.


What About Compressor Air Tools?

If the lubricator is too far away from the item you are trying to lubricate, then oil may not ever get to it. Some lubricators aren’t capable of blending the oil and compressed air fine enough that it will actually carry through the air hose to the application.

Compressor Air Tools

For air tools, consider two or three drops of tool lubricating oil into the air port in the tool before you use it. Before you put the tool away, a couple more drops wouldn’t hurt. That should be enough oil for most tools.

If the application is air cylinders, then make sure that the lubricator is close to the valve that controls the cylinder, and the valve isn’t more than a meter, maybe two, from the valve, or else the oil just won’t be getting to the actuator.


Drips On Lubricator Settings

I’ve had a lot of questions at about setting the drips on an in-line lubricator.

First off, I’ve always been told that 2-3 drips per minute on a continuously used air circuit is ample lube for all but the fastest cycling cylinders or high-volume air tools.

Drips On Lubricator Settings
Most applications could get away with 1 drop per minute, or maybe less. Folks tend to over lubricate.

If you’re not sure about your air tool or application, either contact the tool manufacturer to get their recommendation or the air actuator supplier for theirs.

Once you start lubricating a tool or air actuator, don’t stop doing so. Lube oil you’ve introduced via your lubricator will tend to wash away any factory-installed lubrication, and if you stop adding lube to the circuit, your air tool or cylinder will suffer as a result. There’s more information on compressed air lubricators on this site both to use and if you need one, to buy.


ARO L36121-100-VS Air Line Lubricator, 1/4″ NPT – 150 psi Max Inlet

Hello, I am Bill, the Compressed-Air-Man. I have years of experience in industrial and residential compressed air applications, air compressors and general pneumatics. I created this site to help professionals, students, and DIYers understand and properly implement and maintain compress3ed air systems.


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