What is Predictive Maintenance?

While predictive maintenance is similar to preventative maintenance, in that it seeks to prevent major problems, the two strategies are not the same. In order to better understand what predictive maintenance is, let's first look at the differences.

Preventative maintenance follows a predetermined schedule of recommended tasks intended to keep machinery and vehicles running smoothly – and hopefully preventing major problems from occurring. For example, an equipment manufacturer may recommend a maintenance schedule consisting of routine fluid flushing and belt replacement every six months regardless of whether or not the fluid needs changed or the belts are worn. These items are likely somewhat worn due to wear and tear but the equipment is not necessarily ready to fail. By replacing items before the need becomes critical, this strategy can be effective at preventing problems. It is an essential part of an overall vehicle and equipment maintenance program.

Predictive maintenance often takes place in conjunction with routine maintenance. This strategy involves observing machinery for indications of a potential problem as well as ongoing assessments, performance monitoring, and comparisons to statistical data. Alan Friedman of the Predictive Maintenance Institute of Mexico described the proactive mode of predictive maintenance as the stage where you have enough historical information about machinery and failure rates to make educated decisions about extending their lives, replacing them, or weeding out inherent design flaws.

·       Inspections – Inspections should be integrated with routine service. Since the equipment is pulled out of service temporarily, this is an ideal time to physically inspect equipment for signs of potential problems such as excessive wear, leaks, missing parts, signs of damage, and so on.

·       Operational Assessments – While inspecting equipment during routine service calls is good, assessing it while its operational is even better. When equipment is in operation, potential problems may be easier to see or hear. For example, have you ever heard your car make a strange clunking or squealing sound when driving it? That's often a signal that something is wrong. When changing your car's oil and visually inspecting the car for signs of problems, you might have missed the underlying cause. However, once you start driving the car, the clunking or squealing alerts you that something is amiss. Operational assessments are useful in discovering potential problems.

·       Performance Monitoring – Just as your car has temperature gauges, odometers, and "check engine" lights, industrial equipment has indicators such as operating temperatures, sensors, and counters that should be monitored regularly for performance. These figures should be compared against benchmarks. Deviations from normal benchmarks indicates a possible problem.

·       Statistical Comparisons – In addition to monitoring equipment and comparing its performance to benchmarks, comparisons can be taken even further. Keeping accurate service records and repair histories of all equipment allows maintenance professionals to predict potential failures. For example, let's say that 60 forklifts out of a fleet of 100 have had major transmission problems after just nine months of operations. Using this data, it would be smart to pay attention to newer forklifts of the same make and model as they approach this age as the likelihood of a transmission issue is roughly 60 percent based on historical data. Keeping and analyzing records such as this example is also smart in making future buying decisions.

Predictive maintenance is a proactive strategy that seeks to predict major problems with equipment, machinery, and vehicles.