How to Safely Extend Preventive Maintenance Intervals

Risks associated with extending PM intervals can be mitigated somewhat with careful planning and a solid oil analysis program

Pm Inter

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There are many methods for safely extending intervals. Each depends on the exact PM task you are trying to extend, but at the core of most is oil analysis. Repeatable and representative oil samples with the proper test slates are essential for evaluating the current practices and the possibility of extending those practices.

The first step is to take a deep look into the historical data you have for the component or group of equipment. Groups of equipment should be fundamentally the same and operate within the same environmental conditions. Depending on the type of equipment and PM task you are evaluating, certain trends and data will need to be analyzed. For example, if you want to extend drain intervals for a fleet of diesel engines, look at historical trends of spectrochemical analysis, fuel dilution, soot levels, oxidation, water, viscosity and base number.

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