Oil analysis is an excellent tool that can be used to direct maintenance decisions. However, if you have not chosen the proper test slate, it is wasted time and money. Therefore, one of the first steps toward a successful oil analysis program is determining the right tests to perform. This is especially crucial if you are going the onsite oil analysis route because it will influence the choice of equipment you invest in. Though there are pros and cons to both onsite oil analysis and sending samples to a third party lab for analysis, more and more organizations are shifting to onsite oil analysis due to the speed of results, the accuracy in modern onsite lab equipment, and ultimate cost savings.
Test slate selection can be a bit daunting. Some mistakenly believe that it is too technical or too involved for an untrained individual. It may help to break the selection into smaller segments. For example, first decide whether you want to examine the fluid properties, the contamination or the wear debris.
As shown in the chart above, particle counting can be a great indicator of the effectiveness of your contamination control program, but if you are looking for a test to tell you about the health of your lubricant, the acid/base number and viscosity tests would be much better.
The AMETEK Spectro Scientific MiniVisc 3000 series viscometers provide high-accuracy measurements for easy detection of viscosity variations caused by contamination, mix-up and oil degradation.
You can narrow your focus even further by considering tests based on equipment type.
Qualification testing, quality assurance testing, user acceptance testing and monitoring of new oils in storage are some of the other important categories of oil analysis.
Typically, lubricant manufacturers or blenders will use qualification testing to make sure the lubricant blend meets the stated minimum criteria. Among the tests usually conducted include:
- Oil viscosity and lubricity
- Oxidation stability
- Acidity and/or alkalinity
- Pour, flash and fire point
- Soluble and insoluble contaminants
- Air release and foaming characteristics
- Anti-corrosion and anti-rust characteristics
- Anti-wear and extreme-pressure characteristics
- Water separability and emulsibility characteristics
- Relative cold-weather operating characteristics
A number of other organizations may conduct additional testing to verify performance for specific machine classes. For example, the Society of Automotive Engineers (SAE) and the American Petroleum Institute (API) perform tests for gasoline and diesel engine oils, while the International Organization for Standardization (ISO) and the American Gear Manufacturers Association (AGMA) run tests on gear oils and for viscosity, anti-wear, extreme-pressure and other performance specifications.
Component-specific routine and exception test slates
Quality assurance testing is conducted by lubricant manufacturers during refining and blending to confirm product quality and consistency. These tests are generally limited to oil viscosity and/or viscosity index, sulfated ash, acidity and/or alkalinity, and additive concentration.
Acceptance testing is often some of the first testing performed by end users. It helps ensure that the lubricants delivered match those that were ordered and that deliveries meet acceptance quality standards.
Typical tests include oil viscosity, viscosity index, atomic emission spectroscopy, Fourier transform infrared (FTIR) spectroscopy, water contamination and particle counts.
Finally, there is testing used to monitor new oils in storage. Many are unaware that lubricants in storage have a shelf life. Over time, lubricants suffer the effects of contamination, biological growth, oxidation and degradation byproducts.
If oils are stored for an extended period of time, they should be tested to verify that they have not deteriorated to the point of becoming useless.
The table above provides component-specific routine and exception test slates for the majority of equipment used in plants today. Several of the tests listed as routine are fairly simple and can be performed in-house.
At minimum, I would recommend that you have a particle counter and viscosity comparator to make certain that the lubricants you are receiving are labeled correctly. Having the ability to conduct onsite particle counts can save you money by providing quick information on the effectiveness of your contamination control program.
The MiniLab 153 measures fluid contamination via the LaserNet particle counter that provides total particle count, size distribution and ISO codes as well as a count of non-metallic particles.
| 46% | of lubrication professionals use onsite oil analysis testing at their plant, based on a recent poll at MachineryLubrication.com |
Of course, there are many reputable oil analysis laboratories that will work with you to select test slates targeted to your equipment and processes, but you must educate yourself to guarantee that you are getting your money’s worth and that your oil analysis program is aligned with your reliability goals.
Besides the name of the test, be sure to ask which test method is utilized. If the lab is not able to identify the ASTM method being used, this would be a good indication to terminate the partnership.
Bottom Line
Selecting the right oil analysis tests is crucial for effective equipment maintenance. By focusing on the specific needs of your machinery, such as fluid properties, contamination, or wear debris, and working with a reputable oil analysis laboratory or, even better, investing in trusted onsite lab equipment, you can ensure that your program is both cost-effective and aligned with reliability goals. It's essential to stay informed about test methods and collaborate with reliable partners to make the most of your oil analysis efforts.
Read more on oil analysis best practices:
4 Oil Analysis Tests to Run on Every Sample
How to Interpret Oil Analysis Reports
Statistical Techniques to Simplify Oil Analysis Data
