By Jim Fitch
Journal of the Society of Tribologists and Lubrication Engineers
Most often, users associate an oil analysis program with a systematic early alert to oil or machine failure, i.e., damage control. While these benefits are helpful and frequently achieved, they should be regarded as low on the scale of importance compared to the more rewarding objective of failure avoidance.
Whenever a proactive maintenance strategy is applied, three steps are necessary to insure that its benefits are achieved. Since proactive maintenance, by involves continuous monitoring and controlling of machine failure root cam:es, the first step is simply to set a target, or standard, associated with each root cause.
In oil analysis, root causes of greatest importance relate to fluid contamination (particles, moisture, heat, coolant, etc.) and additive degradation. However, the process of defining precise and challenging targets (e.g., high cleanliness) is only the first step. Control of the fluid’s conditions within these targets must then be achieved and sustained. This is the second step and often includes an audit of how fluids become contaminated and then systematically eliminating these entry points. Often better filtration and the use of separators are required.
The third step is the vital action element of providing the feedback loop of an oil analysis program. When exceptions occur (e.g., over target results) remedial actions can then be immediately commissioned. Using the proactive maintenance strategy, contamination control becomes a disciplined activity of monitoring and controlling high fluid cleanliness, not a crude activity of trending dirt levels.
Finally, when the life extension benefits of proactive maintenance are flanked by the early warning benefits of predictive maintenance, a comprehensive condition-based maintenance program results. While proactive maintenance stresses root cause control, predictive maintenance targets the detection of incipient failure of both the fluid’s properties and machine components like bearings and gears. Following the oil sampling procedures, selection of appropriate sample testing procedures, and interpretation of test results outlined in this section, immediate corrective action can then be directed to effectively avoid failure chain reactions and further self destruction.