- Buyer's Guide
As a lubrication and oil analysis consultant, I spend a lot of time teaching others how to improve the reliability of their machinery by improving their lubrication and oil analysis programs. These folks, mostly plant personnel, often have a clear vision of what they would like to achieve, but getting there is not so easy. One of the most common road blocks to achieving reliability improvements is procuring the resources to support our initiatives. In the real world, most of us don’t have unlimited dollars and manhours to solve our problems. Therefore, we must use our existing resources in the most-effective manner to get the biggest bang for our precious buck. As we develop a strategy to increase the reliability of our machinery, we should take a critical look at each machine, group of machines or process in order to define and justify the most appropriate resources to apply to each.
One method that can be used to effectively reduce labor requirements for lubrication is to identify those machines, based on criticality and reliability history, where we can eliminate planned maintenance activities. For example, we probably shouldn’t spend time and money performing vibration analysis on an exhaust fan in the break room. After all, what is the penalty for failure? Is the asset’s reliability acceptable? Will monitoring the condition of or performing preventive maintenance on the fan improve the reliability or safety of the plant? Probably not. While this example may be unrealistic, it certainly makes the point.
There are applications in most industries and plants for which the best maintenance strategy is a reactive one. For these applications, it is appropriate to utilize maintenance-free components such as sealed bearings or sealed-for-life reducers and motors. While it would be possible to extend the life or improve the reliability of these applications through preventive or predictive maintenance, it may not be costeffective, or worse yet, it may come at the expense of the reliability of more critical assets. To decide which strategy is optimum, we need to analyze the life cycle cost of the component. By tracking the initial cost, reliability history, maintenance expenditures, and making a few assumptions, it should not be difficult to choose the most appropriate course.
When determining which components should be included in the oil analysis program, we should once again decide how to achieve the greatest return for our dollars. On more than one occasion I’ve been told “we do oil analysis on everything once a year because that is all the budget allows”. While the best strategy might be to secure the appropriate allocation, that might not be possible. The next best action would likely be to apply effective oil analysis to the number of machines allowable in the budget, starting with the most critical. If it is in fact an issue of getting the necessary funds to properly utilize oil analysis, applying an effective program to a select number of machines will likely show significant returns in a short time which should go a long way toward garnering the necessary support to expand the program.
An effective oil analysis program includes proper sampling hardware and techniques, appropriate test slates, lab quality assurance and effective management of data including alarms and limits. Unfortunately, many will haphazardly perform oil analysis and other predictive maintenance functions, which diminishes or eliminates the value of the program. For this reason, it is easy to understand why some view oil analysis and other condition monitoring tools as an expense rather than an opportunity to improve production and quality and reduce maintenance costs.
Another important goal should be to eliminate activities that have no value. Optimizing the frequency of lubrication tasks by employing a condition-based relubrication strategy or by correctly establishing a frequency based on lubricant quality, the type of application and operating conditions can help eliminate waste. I once worked with a group who changed the oil in all the gearboxes every month in an effort to improve reliability. While I can appreciate their effort, this was not a sound strategy. In fact, they were probably more likely to reduce reliability rather than increase it because if you work on a piece of equipment enough times, you’re likely to break it.
Overgreasing is another common problem that not only wastes time and resources but also causes significant damage to bearings, especially in electric motors. I often see bearings that should be greased annually which are being lubricated monthly instead. Imagine that there are a thousand of these points in a plant, and do the math. That adds up to a lot of wasted time and damage caused by overgreasing.
Developing a world-class lubrication program is not an easy task, and investing money and effort in an indiscriminate fashion will likely yield more frustration than real improvement. It is essential to develop a detailed plan by identifying what tactics should be applied to which machines, optimizing the frequency of PM activities, creating good lubricant specifications and defining the goals of the program.
With a proper game plan, the program should be executed in a logical fashion starting with the most critical components. The final step is to define and track the appropriate metrics to identify and document the success of our efforts. Armed with this data, it should be easy to build support for continued improvements.