Under the Hood - Meeting the Design Challenge of the Fluidscan Handheld Infrared Oil Analyzer
Mid-Infrared (Mid-IR) spectroscopy is widely used for lubricant formulation and evaluation because of the detailed information on chemical composition provided by this technique. In recent years, it has been deployed as a condition monitoring tool in laboratories worldwide providing degradation information of in-service lubricants by measuring properties such as Oxidation, Nitration, Sulfation, Soot and Antiwear Additive depletion. It is widely accepted for this purpose with established ASTM standards (Table 1).
Figure 1 shows a typical infrared spectrum of an oil sample. The regions of the spectrum used to calculate typical oil condition parameters are highlighted to show how the IR spectrums are utilized for this purpose. Usually such spectrums are obtained in a lab with a Fourier Transform Infrared Spectrometer (FTIR), and the analysis is performed by a trained lab technician. Reliability professionals have not adopted FTIR spectrometers for use in the field due to the challenges of miniaturization, sample introduction and the need for direct, high-quality and actionable information without requiring the operator to be a trained oil analyst.
Table 1: Quantitative parameters extracted from oil Infrared spectra and the corresponding ASTM methods and units reported