Practice for Monitoring In-Service Lubricants by FT-IR Spectrometry, ASTM International

This standard practice employs Fourier Transform Infrared (FT-IR) spectrometry to monitor machinery lubricants, hydraulic fluids, and other operational fluids. It tracks additive depletion, contaminant buildup (like water, soot, ethylene glycol, fuels, and incorrect oil), and base stock degradation (such as oxidation, nitration, and sulfonation). The goal is to diagnose machine operational conditions based on observed oil fault conditions.

• Purpose: This practice uses FT-IR to monitor lubricant health, tracking additive loss, contaminant buildup, and base stock degradation in machinery lubricants and hydraulic fluids. It helps diagnose machine condition by identifying issues like water, soot, ethylene glycol, fuels, and incorrect oil, as well as oxidation, nitration, and sulfonation of base stocks
• Methodology: This practice relies on trending and distribution response analysis from mid-infrared absorption measurements
• Application: It can assess general machinery health by measuring properties like water and oil oxidation, visible in the mid-infrared spectrum
• Data Usage: The infrared data generated is typically combined with other testing methods for comprehensive analysis
• Limitation: This practice is not designed to predict lubricant physical properties such as viscosity, total base number, or total acid number
• Scope: This practice is designed for monitoring in-service lubricants to aid in determining general machinery health, but it is not intended for analyzing lubricant composition, performance, or additive package formulations