Challenges in the Analysis and Evaluation of Industrial Oils

1. Introduction

The analysis and evaluation of lubricants and operating fluids is more than routine work – it requires technical know-how, experience, and a precise laboratory infrastructure. With a daily sample volume of up to 2,000 analyses of oils, greases, coolants, fuels, and AdBlue, automated processes in the laboratory and smooth sample throughput are as important as an optimized IT infrastructure for data transmission and analysis evaluation. Ultimately, the customer should be provided with information about the condition of the lubricant and the machine itself, from which recommendations for action can be derived. This presentation aims to highlight the challenges of the analysis process up to the correct evaluation on laboratory reports.

2. Analysis Process

2.1 Definition of Individual Requirements

The definition of the appropriate scope of analysis depends on the specific application or individual question. Standardized analysis kits serve as a guide, but each case is different: water content, aging, particle contamination, mixing, or incompatibilities must be specifically checked depending on the area of application. This often results in individual scopes of analysis that must be taken into account during the laboratory run and sample evaluation. This can already be the case with one application such as an engine: while acids in gas engine oils are particularly critical, fuel entry in diesel or gasoline engines play an important role.

2.2 Laboratory Procedures

After sample receipt, the samples are systematically divided into different analysis batches. Depending on the sample (hydraulic oil, gear oil, grease, etc.), different test procedures or methods are often applied in the laboratory. For example, viscosity measurements are more precise when thin hydraulic oils are measured on different capillaries than high-viscosity gear oils. This must be automated in the LIMS (Laboratory Information and Management System) to ensure a fast and smooth laboratory run. It is essential to regularly measure control standards and perform calibrations on the laboratory equipment itself to exclude any drifting of measurement results or even incorrect measurements. These requirements are not all regulated by standards but often need to be individually optimized in each laboratory. Special flushing procedures in automated measurements also play an important role in avoiding any contamination of the following sample.

2.3 Evaluation and Lab report

Interpreting the results requires experience, as the limit values vary depending on the application and depend on several factors such as runtime, oil type, oil quantity, or environmental conditions. Wear values, aging processes, or water entry must therefore often be evaluated differently even for identical applications.

Although text modules are primarily used for commenting on laboratory reports, these are automatically adapted to a specific application to assign the wear values of an engine to different components than in a hydraulic system. In addition, samples are often sent with specific customer questions. The evaluating tribologists then provide equally individual comments. Overall, the diversity of evaluation criteria to be considered makes the use of artificial intelligence in the evaluation of laboratory reports possible, but there are many degrees of freedom that must be considered. Despite these possibilities, it is the human or tribologist who forms the last link in the process chain before the laboratory report is sent to the customer.

3. Conclusion

The analytical investigation and evaluation of lubricants and operating fluids are complex and customized services. Both profound knowledge of technical and chemical relationships and the use of modern technologies throughout the process are required. Only in this way it is possible to exploit the potential of analytics and support customers in recognizing problems with machines early or extending oil change intervals.