Routine oil analysis is recommended by every major air compressor OEM precisely because they understand just how important oil condition and performance are to compressor reliability. They also understand just how vulnerable oil-injected rotary screw compressors are to their environment and operating conditions, and how beneficial oil analysis is at detecting oil and compressor problems before they occur.

The typical compressor manual instructs its users to perform routine oil analysis every 2,000 hours and replace the oil “every 8,000 hours, or once a year, or as determined by oil analysis (and here’s the suspicious part)… WHICHEVER OCCURS FIRST!”  In other words, the OEMs insist you perform oil analysis and act on the results, but only when it benefits them and results in a premature oil change (increased oil sales).  But what if your compressor’s oil has 8,001 hours in service, or even 80,000 hours as some Fluid Metrics’ customers have experienced, and its physical and chemical properties were still good as new?  What if the oil analysis results benefit the user by confirming the oil still has plenty of useful life remaining, and that no oil change or new oil purchases is warranted?  If any oil supplier suggests that oil analysis should ever be ignored and the oil’s time in service is more instructive than its physical and chemical properties, they are dead wrong and you’d be right to question their motivation and begin looking for another oil supplier.

So which tests or oil analysis package is best for rotary screw air compressors?  The answer is NOT the standard “industrial” oil analysis packages supplied by most compressor companies and oil suppliers.  These generic one-size-fits-all packages are designed by the labs for quick and easy processing, and typically include only the most basic information.  Much of this information is useless when monitoring rotary screw compressor oils, and these standard packages fall well short in terms of both the specific tests performed and test methods used.  Knowing which tests to perform and the best methods to use is vital to any oil analysis program.

Fluid Metrics specializes in air compressor fluids and their analysis, and our experienced team of Chemists and Engineers are experts in optimizing compressor oil performance and service life.  Decades of compressor industry experience has taught us which oil analysis tests provide the most accurate and valuable information, while delivering the best bang for our customers’ buck.  We also understand the unique vulnerabilities of rotary screw air compressors and the critical relationship and impact that acids and additives have on oil performance and service life.

Our compressor oil analysis package was developed specifically for rotary screw air compressors in conjunction with our Chemists and one of the world’s oldest and most trusted labs. Unlike the generic test slate others use, our analysis includes three separate acid metrics to provide a more accurate picture of what’s going on with your oil. We monitor both the weak acids naturally produced inside your compressor by oxidation, as well as the strong acids that are the result of “acid-gas” contaminants ingested from the environment.

Like a blood test for your compressor, oil analysis provides vital information essential for proactive, Reliability-centered and condition-based maintenance. And when used properly, regular oil analysis is proven to increase the reliability of your air compressors, optimize your maintenance activities and reduce costs. Allow Fluid Metrics to become your compressor oil analysis partner, and let us show you just how much easier, better and less costly your compressor maintenance can be. Call us today.


  • Detect & Prevent Hidden Problems Before They Occur
  • Increase Oil Service Life & Optimize Change Intervals
  • Improve Component Life & Equipment Reliability
  • Reduce Equipment Downtime
  • Improve Plant & Worker Safety
  • Reduce Oil & Parts Consumption
  • Reduce Maintenance Costs