through an extensive self-assessment based on generally accepted
standards for maintaining and managing a lubricant testing labora-
tory. In recent years, ASTM D7776-12 (Self-Assessment of Quality
System Practices in Petroleum Products and Lubricant Testing
Laboratories) has been developed to better outline the specific
criteria that should be reviewed. If possible, end users should request
any documents that can provide the results of laboratory self-as-
sessments and the methodology and criteria that were employed.
If only raw data from the oil analysis tests is presented in the
final report, it can be quite confusing and overwhelming for
end users who have little to no interpretation experience. To
achieve the end goal of oil analysis, there must be a compre-
hensive interpretation of the data. The interpretation stage
can be challenging to summarize, as each oil analysis test
provides different forms of data. Nevertheless, some general
guidelines should be followed during the interpretation of
routine oil analysis.
First, the overall results should focus on verifying or identifying
the three oil analysis categories: fluid properties, contamination
and wear debris. Second, tests performed on a single sample will
not be sufficient to obtain quality results. Developing statistical
trends of specific data points and calculations across multiple
data points will likely be required to determine if there are any
concerns. Perhaps the most important comparison will be against
the baseline sample results (new oil test results from the same
batch of the used oil result).
The various trends developed for each sample point along with
3. Interpretation
• Three categories of oil analysis
• Statistical trends and calculations
• Multiple data point correlations
• Maintenance history considerations
32%
of lubrication professionals
are not confident in the validity
of their oil analysis data,
according to a recent poll at
MachineryLubrication.com
ML
