In teaching courses on how to establish a best-in-class lubrication program, I often talk about value-added tasks: activities that can significantly extend equipment life, increase asset reliability or eliminate unwanted downtime. A good example would be using a filter cart to periodically decontaminate gearboxes. Done routinely or in response to elevated particle or water levels, there can be little doubt that offline filtration has a significant effect on gear and bearing life.
But despite a general acceptance that these value-added tasks work, many companies have yet to implement these types of programs to supplement their routine, time-based lubrication preventive maintenance (PM) routes. The question is why? Surely if we believe they have an effect, integrating value-added tasks into the daily work schedule is a no-brainer?
Whenever I ask, “Why haven’t you developed value-added tasks?”, I’m often given a few different reasons:
- “We don’t have the money to invest in new hardware.”
- “Management won’t support us.”
- “Our equipment is not readily accessible during production.”
But by far the most common response is “we don’t have the resources to get done all that needs to be done just to keep this place running. We don’t have time for any new initiatives.”
Having spent time in numerous U.S. manufacturing plants in the past 18 to 24 months, there can be no doubt that there’s truth to this statement. Even more so today than ever before, companies are trying to do more with less, leaving little time for new programs or initiatives to take hold. So, faced with this reality, which is unlikely to change in the foreseeable future, we can respond in one of two ways: accept that despite our best intentions or desires nothing will change, or find a way to make it happen.
So, how can we find time to develop and deploy new practices? How can we be more efficient in the way we execute on lubrication PMs, working smarter instead of harder? From my experience, there are two strategies, both of which offer the potential to free up significant man-hours. The first is to eliminate non-value-added tasks – activities that either don’t contribute any benefit to the organization or, in many cases, are downright detrimental. Some good examples are changing oil that does not need to be changed or greasing bearings too frequently. In many plants, as much as 25 to 35 percent of all lubrication tasks might be considered to be non-value added. The key to addressing this is through lube PM optimization – deciding which tasks need to be done and what is their optimum frequency. I’ve talked at length about the optimization of lubrication PMs in previous articles. But there’s another way in which we can find efficiencies in the way we execute lubrication work – specifically, through more effective planning and scheduling. This is the area on which I want to focus for this article.
The Issues With Conventional Routes
When it comes to scheduling lube PMs, many organizations combine their routine lubrication PMs into routes – a compilation of tasks that are similar in task type, area of the plant or tools required. With this approach, we end up with lube routes that tend to be named things like “electric motor regrease”, “pillow block bearing regrease”, “oil level inspection and top-off” or “routine oil sampling”. Typically, these routes are scheduled based on task frequency. For example, the electric motor regrease route may be scheduled to be done every six months, the inspection and top-off perhaps weekly, greasing of pillow block bearings monthly and oil sampling routes done quarterly. But is this the most efficient way to execute work? In my opinion, it is not.
To illustrate the potential problems this approach creates, consider the simple example of executing these lubrication PMs on a belt conveyor. Every week, we receive paperwork instructing us to walk down all wet sumps, check the oil level and top-off where necessary. Following our work instructions, our diligent lubrication technician walks down the conveyor to check the oil level on the gearbox, along with other oil sumps in the same area of the plant.
Having completed the top-off and inspection route, we now receive our next work instructions: Perhaps it’s time to grease motor bearings – a six-month task. Our diligent lube tech now grabs the grease gun filled with our designated electric motor grease and duly executes the work.
Next, it’s time for our monthly regrease of the head, tail and other conveyor pulley bearings. Returning to the lube room, the tech takes the grease gun with our multi-purpose EP 2 grease and heads back out to the conveyor to grease the bearings, passing by the gearbox and motor to grease the head pulley bearings.
Finally, our lube tech is ready to take oil samples. Once again, returning to the lube room to obtain the appropriate sampling paraphernalia, the tech heads out to the head of the conveyor to sample the gearbox along with other wet sumps on his sampling routes – a task that needs to be executed every three months. Exhausted from a busy day, our lube tech is ready for a much-deserved night of rest ... before it all starts again in the morning!
Dynamic Planning Increases Wrench Time
Now, let’s consider the inefficiencies that this type of lube task planning and scheduling creates. Of the eight-hour workday, how many hours is our tech actually doing value-added work, as opposed to collecting supplies, paperwork or traveling to/from the job sites?
In the maintenance and reliability field, the time spent doing work as opposed to every other aspect of planning, kitting and traveling to the job is called “wrench time”. For many organizations, wrench time barely exceeds 25 to 30 percent, meaning that out of an eight-hour day, only two to 2.5 hours of useful work is actually getting done. Conversely, world-class companies have wrench times in the range of 50 to 60 percent. Compared to 25 percent wrench time, a wrench time of 50 percent equates to effectively having twice as many people to do the work required. (This is a concept sometimes referred to as the “hidden staff”.) For most plants, loss of wrench time comes from paperwork, obtaining supplies and travel time to/from the job site.
Now, let’s think about the execution of the lube tasks prescribed for our belt conveyor. The actual time to grease the motor or pillow block bearings, take an oil sample or check the oil level is miniscule compared to the time to obtain the PM worksheets, gather the required tools and walk to the lubrication point in question. For all but the smallest plant, this is always true – the bulk of the time is not spent executing value-added lubrication tasks but in preparing to execute the tasks.
OK, how can we be more efficient in the way we plan, schedule and execute work? The answer is actually very simple: Forget about task frequency! That’s not to say that we shouldn’t adhere to the optimum periodicity for lubrication PMs, but rather we should not consider the frequency in compiling the block of work to be done in any given work day or week.
This approach, called “dynamic route planning”, allows for any task that is geographically related or requires the same or similar tool set to be executed on the same assignment sheet. While this takes some time to establish, deploying dynamic route management really creates far more efficiency in kitting and traveling to the job site.
Using this approach for our belt conveyor, we find that, one week, the assignment sheet may simply state: “Check oil level in to the full running mark. If level is too low, top off using oil XYZ, as necessary.” But every fourth week, an additional task appears: “Regrease the pillow block bearings”. The key here is that the weekly and monthly tasks appear on the same assignment sheet, in the correct sequence, so the two tasks can be executed at the same time. This is far more efficient than walking back to the lube room between tasks.
Once a quarter, our oils sampling tasks also appear, while every six months, a fourth task (grease the electric motor bearings) is included in our dynamic assignment sheet, so this can be done at the same time as checking the oil level, greasing the pillow block bearings and taking the oil sample.
Time Well Spent
Using this simple example, it should be apparent that dynamic route planning offers a very significant advantage over our conventional approach of frequency-based lube routes. Instead of walking to and from the lube room, locating and gathering different tools, and handling paperwork before executing the work, dynamic route planning allows those tasks that logically fit together to be done at the same time, no matter what their prescribed frequency.
So, next time you look at how you execute routine time-based PM work, think about where most of the time is spent: Is it in actually doing valued-added work, or are you spending most of your days preparing to do work?
As always, this is my opinion, I’m interested to hear yours.
