How to Correlate Analysis for Oil

If you’re interested in understanding the composition of oil, you’ll need to do a bit of analysis. Some of the basic measures that you’ll need to make include particle count, HRA, viscosity, and TBN. Then you’ll need to know how to correlate the results of these measurements to get the most reliable information. There are a variety of techniques you can use to do this, including cyclic thermodynamics and phase inversion correlations.

Viscosity

The use of oil viscosity analysis is crucial in any maintenance or repair process. It helps to determine the condition of the oil, which affects the working performance and the life of the equipment. Excessive viscosity can lead to excessive friction and heat. Moreover, it may affect the operating pressure.

This type of oil analysis is commonly used in the industrial environment. Some common instruments include the rotary viscometer and the kinematic viscometer. Both of these methods are very accurate. Nonetheless, there are still some challenges when it comes to testing oils.

Most of the tests are performed on machinery. Nevertheless, there are also some onsite oil analysis instruments available. These tools can be used to detect changes in viscosity and density.

Phase inversion correlations

Phase inversion is a process that occurs when a fluid changes from a continuous to a dispersed phase. It can affect flow patterns, pressure drop, and energy consumption. There are several models that can be used to predict the point of inversion. However, most models only cover a narrow range of operation.

The most popular model is the dual differential pressure model. This model allows for accurate measurement of overall mass flow rate in oil-water two-phase flows. In addition, the model can be used without the use of a secondary instrument.

Another model uses a correlation between the flow pattern transition and the average liquid mixture film thickness. Both models provide predictions for the overall mass flow rate with +-5% accuracy.

TBN

A Total Acid Number or TBN, is an important parameter to know. It explains the level of alkalinity in a lubricant. The TBN is expressed as milligrams of potassium hydroxide in one gram of lubricant.

An engine oil’s ability to neutralize acids plays a big part in its lifespan. The more sulphur in the fuel, the more acidic the oil will be. Adding additives helps to balance out the acidic compounds in the lubricant.

TBN is measured using a number of methods. The most common is the ASTM D2896 test. This method is designed to detect soft and hard TBN.

For this test, a sample is titrated with an ethanolic solution of potassium hydroxide. Various solvents are used in the process.

Particle count

Particle count analysis for oil is an important part of any oil analysis program. Using particle counts, maintenance professionals can quickly determine whether a lubricant is clean or contaminated. Often, the particle count is combined with other test results for a more complete picture of the lubricant’s cleanliness.

Particle counts are commonly reported in ISO Codes. These codes are scale values that derive from actual particle counts. It is common to report these codes in three size ranges. This makes it easy to compare the particle count between different sizes.

The ISO 4406 industry standard simplifies reporting particle counts by defining an ISO Code and providing a number of particle count tests. Various particle count testing techniques can produce significantly different results.

HRA

In the petroleum industry, human reliability analysis (HRA) is an emerging field of research that helps to determine the likelihood of an event causing a major accident. HRA can be used to identify hidden problems that may have adverse consequences. It should be used in conjunction with other risk analysis techniques.

There are several challenges that affect the performance of HRA methods. One challenge is the need for HRA to be tailored to the specific activity requirements of the operator. Another challenge is the lack of guidance for when to use HRA and how to integrate it into the overall QRA.

A third challenge involves the evaluation of PSFs. The time-based PSF is an important part of evaluating the performance of an individual operator. However, the Time PSF is often difficult to assess since there is no empirical data to support the assumptions.