Choosing Lubrication for a Rotary Screw Air Compressor

Choosing Lubrication for a Rotary Screw Air Compressor

Any kind of machinery that involves the meshing of parts needs to have lubricant to operate correctly without building up damaging friction and heat. Even parts that are fine-tuned to exact cooperation will create friction and expand at the molecular level as a result. This then creates tolerance problems and ultimately, catastrophic failure. The age-old classic example is an engine piston seizing inside the engine chamber when running hot. Lubrication, on the other hand, prevents friction from occurring or mitigates it sufficiently that even while hot the damage problem doesn’t occur. Over time, however, even lubrication breaks down, and this is where maintenance and replacement play a critical role.

Compressor Lubrication

Rotary screw air compressors have multiple assemblies that involve moving, interoperating parts. These parts have to be lubricated correctly to avoid the above from occurring. While any machine lubrication could technically do the job immediately. It’s not recommended. In fact, what should be used is the lubrication that has long-lasting capability even with heat build-up, that doesn’t break down quickly over time and ideally helps protect the metal parts instead of allowing friction damage and possibly corrosion. Even sealed or oil-free systems that don’t require lubrication replacement utilize internal protection to prevent motion damage to the parts.


Modern rotary screw air compressors utilize an injected oil system to ensure the lubrication is provided where it needs to be and at the right number continuously through running operations. Because of this design, the correct machine oil needs to be used specifically for the compressor model and build. Ideally, a specific OEM oil has been identified by the manufacturer in the owner’s manual or provided by the manufacturer directly. This is common where a compressor manufacturer guarantees the machine oil recommended. Alternatively, a manufacturer could recommend a handful of third-party machine oils of high quality. These should be considered first above other choices as, again, the manufacturer has tested and confirmed their viability for use with the given compressor model.

Remember, simply using a compressor oil is not enough. Good maintenance of a rotary screw air compressor also involves making sure a regular leak detection inspection is performed where such problems are most likely. One could use the best compressor oil possible, but if it leaks out of the system the lubrication becomes useless and a big mess. At a minimum, a compressor should be put through a thorough maintenance check on parts, connections, couplings, and similar every calendar quarter.

Don’t Be a Statistic

As noted above, lubrication is a low-cost prevention tool for a quality rotary screw air compressor. A catastrophic failure due to friction and parts breaking can be exponentially far more expensive and is entirely avoidable with scheduled care and inspection.