Oil analysis

What is oil analysis?

Oil analysis is one of the most critical aspects of asset maintenance. Oil analysis allows you to determine the condition of an engine or motor and how it can be maintained. It works by taking a sample of oil, which will then be analyzed for metals and moisture. The results from this process help determine if there are any problems with your assets that need to be addressed right away or in the future.

How is oil analysis conducted?

Oil analysis involves examining the oil's physical, chemical, and sometimes microscopic properties to assess its quality, detect contaminants, and identify potential equipment problems. Here is a general overview of how maintenance teams conduct oil analysis:

1. Sample collection: A representative oil sample is collected from the equipment using specific sampling procedures. It is essential to ensure that the sample is taken from a well-mixed portion of the oil, typically through a dedicated sampling port or valve.
2. Sample identification: The sample is labeled with relevant information, such as equipment identification, sampling date, and location. Proper identification is crucial for tracking and interpreting the results accurately.
3. Laboratory testing: The collected oil sample is sent to a specialized laboratory equipped with instruments and expertise for oil analysis. The laboratory conducts a series of tests to evaluate the oil's properties. These tests may include:
   • Physical tests: The oil's viscosity, density, and appearance (color, clarity) are measured to check for deviations from the expected values.
   • Chemical tests: Various chemical parameters are analyzed, such as elemental composition (using techniques like atomic emission spectroscopy or inductively coupled plasma spectroscopy) to detect wear metals, contaminants, and additives. Acid number and base number tests determine the oil's acidity or alkalinity, which can indicate potential oil degradation or contamination.
   • Spectroscopy: Spectroscopic techniques like infrared (IR) or atomic absorption spectroscopy (AAS) are used to analyze the oil's molecular structure and identify specific compounds. This helps identify oxidation, degradation, or contamination by fuel, water, or coolant.
   • Particle analysis: Microscopic examination is performed to quantify and characterize any solid particles suspended in the oil. This analysis can help identify wear, debris, dirt, or other contaminants that may cause equipment damage.
4. Interpretation of results: The laboratory generates a comprehensive report based on the test results. Trained analysts interpret the data, comparing it to established limits and standards for the specific application. The report highlights any abnormal conditions, signs of wear, contamination, or degradation in the oil. It may also provide recommendations for maintenance or further investigations.
5. Maintenance decisions: Based on the analysis results, maintenance personnel can make informed decisions about the equipment's condition and take appropriate actions. This may involve changing the oil, filtering or purifying it, investigating potential problems, or scheduling maintenance tasks.

Discover where oil analysis fits in and the differences between preventive and predictive maintenance

What are the types of oil analysis tools?

Various types of oil analysis tools and equipment are used to perform oil analysis and monitor the condition of lubricating oils. Here are some common types of oil analysis tools:

• Sampling equipment: Proper sampling is crucial for accurate oil analysis. Sampling tools include vacuum pumps, bottles, tubing, and sampling ports/valves. These tools are used to collect representative oil samples from the equipment being monitored.
• Viscometers: Viscometers measure the oil's viscosity, a critical property indicating the oil's resistance to flow. There are different types of viscometers, such as kinematic viscometers, rotational viscometers, and portable viscometers. These tools help assess the oil's ability to lubricate and protect the equipment.
• Spectrometers: Spectrometers are used for elemental analysis of the oil. They can detect and quantify the presence of wear metals, contaminants, and additives in the oil. Techniques such as atomic emission spectroscopy (AES), inductively coupled plasma spectroscopy (ICP), and X-ray fluorescence (XRF) spectroscopy are commonly used for this purpose.
• Infrared (IR) analyzers: Infrared analyzers utilize infrared spectroscopy to analyze the molecular composition of the oil. They can detect degradation, oxidation, contamination, and the presence of water, fuel, or coolant. Portable infrared analyzers are particularly useful for on-site or quick analysis.
• Particle counters: Particle counters measure and count the number and size distribution of solid particles suspended in the oil. These tools help monitor the cleanliness of the oil and detect abnormal wear or contamination. They can provide valuable information about the condition of the equipment and the effectiveness of filtration systems.
• Ferrous debris monitors: Ferrous debris monitors are specialized instruments that detect and measure ferrous (iron-based) wear debris in the oil. They use magnetic or optical sensors to quantify the concentration of iron particles, providing insights into the severity of equipment wear.

Example of oil analysis

Let's say your maintenance team determines the condition of a fleet vehicle's engine and how well it can be maintained. The process involves testing the oil in a car, which a mechanic or machine can do. Oil analysis results are used to determine what type of oil you should use in your vehicle and when it needs to be changed out. This can help you avoid costly repairs down the line since changing your engine's oil regularly helps keep it running smoothly for extended periods.

What are the benefits of conducting oil analysis?

Here are some benefits of oil analysis:

• Early detection of equipment problems or impending failures.
• Optimal maintenance scheduling based on the condition of the oil.
• Extended equipment life through proactive maintenance.
• Improved equipment reliability and reduced downtime.
• Cost savings by preventing major breakdowns and unplanned repairs.
• Increased operational efficiency and productivity.
• Improved safety by ensuring equipment operates within specified parameters.