Any pursuit intended to produce excellence needs a performance metric - machinery lubrication is no exception. Industry needs a metric that wholly measures the organization’s effectiveness at lubricating its machinery. I wish to propose a new metric called Overall Lubrication Effectiveness, or OLE, to serve in this capacity.

If used properly, a performance metric works like a compass for the organization. It helps you find your bearings and get on the right track when performance is substandard. Once the organization is performing on target, metrics help to keep it on track and facilitate continuous improvement. Likewise, it can serve as a common denominator for comparing plants within the organization, or even benchmarking entire industries. It also serves to get the team moving in the right direction. When we know something is being measured, trended and managed, it affects our behavior.

Performance metrics, also called key performance indicators (KPI) can take many forms. Some are global measurements, like return on net assets (RONA), while others are specific, like average cycle time for the No. 26 injection-molding machine. Any metric can be useful as long as it is valid (measures what is intended to be measured), reliable (repeatable), relatively easy to measure, aligned to the mission of the organization and understandable by those who use it to do their jobs.

Many organizations presently measure overall equipment effectiveness (OEE) which is the product of Availability x Quality Rate x Yield.

Simply stated, it measures the plant’s performance compared to the theoretical maximum production rate for the assets. OEE is a powerful metric that gives management an overall look at production effectiveness and eliminates the practice of hiding reliability shortcomings into scheduled downtime. The proposed OLE employs a similar structure as the OEE, but focuses on variables that constitute effective machinery lubrication. The general equation for OLE is the product of the following three lubrication program-related factors:

  • Percent compliance to scheduled lube PMs
  • Percent compliance to contamination control targets
  • Percent compliance to lubricant quality targets.

OLE is intended to measure an organization’s performance in machinery lubrication, a critical input to machine reliability, and ultimately, profitability. Percent compliance to each of the target goals was selected because it is easy to calculate and easy to understand. If your OLE is increasing toward your target or holding steady above your target, you are in good shape or heading in the right direction. If your OLE begins to trend southeast, or holds steady below your target level, you need to intervene and make corrective actions. Let’s look at the input variables in more detail.

Calculating OLE
OLE = PClpm x PCcct x PClqt

Where: OLE = Overall lubrication effectiveness

PClpm = Percent conformance - lube PMs

PCcct = Percent conformance - contamination control targets

PClqt = Percent conformance - lube quality targets

Percent Compliance to Scheduled Lube PMs
Many lubrication tasks are scheduled activities related to performing inspections, sampling for oil analysis, regreasing, top-ups and scheduled oil changes (where condition-based oil changes aren’t feasible). Several common problems exist with respect to completion of scheduled PMs. First, supervisors often pull designated technicians away from lube PMs to help with repair or to perform a number of other tasks within the plant. In some plants, lube technicians are called away from lubrication tasks 50 percent of the time or more. These PMs either pile up or get canceled, so they are not done until the next time they come up on the schedule. Another problem, often referred to as “pencil whipping,” is the act of falsifying PM completion forms. This occurs when technicians have an overly heavy workload or they fail to see the relevance of a particular PM or group of PMs.

  1. The keys to success in performing lubrication PMs include:
  2. Optimize PM tasks so that each one is relevant.
  3. Develop easy-to-follow written procedures for completing the tasks.
  4. Train people to perform the tasks so they understand why those tasks are important.
  5. Periodically audit completion and quality.

PM task lists can grow organically in the organization. There are many reasons why this is so. For example, the unexplained failure of a machine often prompts the scheduling of precautionary PMs, which stay in the system unless someone intervenes to eliminate them later.

Optimizing PM tasks should be undertaken to identify any unnecessary tasks that are being performed, and to develop PMs for important tasks that are not scheduled. Because the business and technology environments are dynamic, implement a periodic evaluation and improvement process to reoptimize PM task lists as required.

Measuring the percent conformance to PM completion targets is fairly simple. If the PM is scheduled and it is completed, that task is in conformance. If it is not completed for whatever reason, the task is nonconforming. Report what percent of the total was completed. To manage against so-called pencil whipping, it may be necessary to institute a random audit of PM task completion. It is also sensible to randomly audit the quality of tasks being completed.

Percent Compliance to Contamination Control Targets
Contamination control is proactive maintenance. Managing contaminant levels at or below prescribed targets helps to assure the reliability of mechanical equipment. The most common contaminants are particles, moisture, soot - a special category of particles (engines), fuel (engines) and glycol coolant (engines). Contamination in any form can cause machine wear, promote lubricant degradation and/or otherwise compromise the performance of the lubricant. Success lies in the organization’s ability to focus effort at controlling contaminant ingress at the source, then removing what can’t be excluded.

The factor of percent compliance to contamination control targets aggregates the organization’s performance in various aspects of contamination control. This includes new oil management and dispensing practices, filter selection and maintenance, breather selection and maintenance, seal selection and maintenance, proper combustion management and other aspects of effective contamination control. If the machine is not in conformance, one or more of the above named (or other) sources of contamination requires attention.

Used oil analysis serves as the measurement apparatus for the contamination factor. Start by establishing meaningful target levels for each of the machines, taking into account mechanical sensitivity, application and/or environment severity and the machine’s criticality to production, safety, environmental protection and/or other aspects of the mission. Compare the actual performance to targeted performance and report the percentage of the machines that comply with contamination targets.

Example Overall Lubrication Effectiveness Trend

Percent Compliance to Lubricant Quality Targets
To operate reliably, the machine must contain the correct lubricant, the lubricant must be fit for service and the lubricant must be kept in the machine. Applying the incorrect lubricant or allowing the lubricant to become disabled due to chemical degradation and/or additive depletion can result in increased rates of mechanical wear and/or corrosion. Leakage of the lubricant can compromise the machine and create risk of injury and/or environmental mismanagement penalties.

The keys to success in assuring lubricant quality are to select lubricants properly, store and deliver them in a way that will minimize mixing and reduce chemical degradation, minimize aeration, run the machines as cool as the application will allow and monitor regularly with oil analysis.

Like contamination control, monitoring compliance to lubricant quality targets depends heavily upon used oil analysis and factors in consumption ratio trending. Baseline the lubricants and set alarm points for properties such as viscosity, acid number, base number, FTIR-oxidation, FTIR-nitration, FTIR-additives, atomic emission spectroscopy-additive metals, RPVOT, etc.; and establish leakage rate targets for each machine against which actual leakage can be compared. Report the percentage of lubricants that conform to these lubricant quality targets.

Be Honest With Yourself
OLE, like other global metrics, is designed to give management an overview of how well the organization is lubricating its equipment. The real work for lubrication and reliability engineers and technicians is in the factors themselves. As is the case with other global metrics, you can work to either improve your program, or work solely to improve the number. By including just a small percentage of your plant, leaving out equipment that is hard to deal with lubrication-wise, initiating flimsy contamination targets and lube quality alarms, arbitrarily cutting out PMs or falsifying records, you can make the OLE look good. A good OLE does nothing for the organization unless it is inclusive, based upon true best practice, and honestly reported. Work honestly and earnestly to make your program better, and allow the OLE to serve as a measuring stick for management, as it should.

At an aggregate level, the organization must establish a goal for the OLE metric. The approach will vary somewhat from one organization to the next. In time, hopefully a standardized method by which the OLE is calculated will be implemented, perhaps by industry type, so benchmarks for performance levels can be made on a macro scale. In the meantime, develop your OLE targets and calculation methods - ideally for a group of plants.

Trending an overall performance metric like the proposed overall lubrication effectiveness (OLE) helps to drive improvement, keeps everyone focused and serves as a rallying point to get and keep the team members working in the right direction and aligned to the goals of the organization. This is my viewpoint. As always, I am interested in yours.