Modern grease analysis in industry

Every machine requires maintenance. While current methods such as oil and grease analysis are well-established in the industry, this is an inexhaustible topic. Modern testing methods provide opportunities to detect early signs of system wear, monitor lubricant condition, and identify external contamination. This presentation will focus primarily on grease analysis, sampling concerns (ASTM D7718), and new technology — the Grease Thief Analyzer GTA (ASTM D7918) — but will also touch upon oil diagnostics.

The new method of grease testing allows us to measure grease consistency under dynamic conditions, providing more accurate insights into grease flow within bearings compared to standard static consistency tests (such as cone penetration – the NLGI grade). The results can indicate whether relubrication is necessary or if the interval between relubrications can be extended or shortened. While there are already devices that measure particle content in oil, what about grease?

Another advantage of the GTA is its ability to determine the "cleanliness class" of the grease. The analyzer can not only quantify particles but also identify their origin. The GTA is currently applied in the wind power industry, but it has many other potential uses as well. These will be presented in the form of case studies. This presentation will also cover the standards for proper grease sampling and how to obtain the most representative samples.

With only a small sample size—1 to 2 grams—it's possible to perform comprehensive GTA testing along with other diagnostic parameters. This is a new method for grease analysis and consistency measurement. Finally, the role of oil and grease diagnostics in the context of Industry 4.0 will be discussed.