Sampling Frequency
How often should sampling be performed? This is not a simple question. Basically, it is a tradeoff. Sampling less frequently can risk missing a machine or lubricant failure, while sampling more frequently can risk wasting time and money (and even lubricant). A better question would be, “What are the variables that help calculate the optimum sampling frequency?” These variables would include the machine age, oil age, target tightness, fluid environment severity and economic penalty of failure. For a description of each variable, see the sidebar above.