Does it annoy you that in spite of regularly performing Preventive Maintenance (PM) on your equipment it continues to breakdown? Some may call this insanity – Continuing to do the same thing over and over, expecting a different result. So what do you do? Maybe take a close look at your current PM Program. There are known best practices which will not only enhance your PM program but also increase equipment reliability. Remember most work comes from PM and PdM and then it must be planned correctly, scheduled with production, executed to schedule and to specifications. If this occurs you will be seeing the results. "less breakdowns" Check out this article and post your comments please.

1. AhM
ion
decisort
supp
Why Your
Preventive Maintenance
Program Isn’t Working
“It isn’t what you know that will kill you,
it is what you don’t know that will.”
asset
health
management
Ricky Smith, CMRP
D
oes it annoy you that in spite of regularly performing Preventive Maintenance (PM) on your equipment it continues
to breakdown? Some may call this insanity—continuing to
do the same thing over and over, expecting a different result.
If you sat down and graphed out your company’s PM labor hours
versus emergency labor hours what would you find? In the chart
below we find PM labor hours flat however emergency labor hours
rising which indicates the PM program is not effective.
reliability is the detection of a defect early enough that a part or
equipment change out or repair can be planned and scheduled in
a proactive state.
The example below displays the P-F Curve where “P” is the point
at which an abnormality begins (defect). The key is that we want
to identify a defect (potential failure) as early as possible so we
have the time to plan, schedule, replace or repair the item before
it fails. Point “F” is the point of functional failure. This is where the
item can no longer deliver its intended designed function. At this
point there is typically a very small amount of time before total
failure where catastrophic damage could occur, which is not good
unless Run-To-Failure (RTF) is part of our maintenance strategy. If
RTF is your maintenance strategy for specific equipment, contact
me and let’s talk about this issue.
Figure 4: Have seen this problem before? How do you PM this equipment?
of security that you have evolved into a Best Practice or World
Class organization.” Let’s be clear, it is impossible to evolve into
Best Practice; it must be carefully engineered.
In fact, after numerous benchmarking studies, data states factually that most maintenance organizations are doing almost exactly
the same type of maintenance they’ve always done. Now here’s
the scary part: a closer look at all Preventive Maintenance (PM)
tasks reveals that on average:
• 30% don’t add value and should be eliminated
• 30% should be replaced with Predictive Maintenance (PdM)
tasks
• 30% could add value if re-engineered
What that means to you is that less than 10% of your PMs are
truly adding value as written. Or in other words, potentially 90% of
your PM tasks should be eliminated or changed. What’s worse, when
you conduct unnecessary, invasive maintenance, you actually introduce variability and potential defects into your asset and process reliability? That’s right! You are actually causing some failures
and you don’t even know it!
Figure 5: Prioritizing Work Using Asset Criticality and Defect Severity
4. Develop a complete understanding of the failure modes that
are present or may be present in your components. These failure modes come from two places: 1) the inherent design of the
machine; and 2) the operating context in which they are used
on a daily basis.
5. Perform a Preventive Maintenance Evaluation (PME) where you
identify each PM Task and any connection it may have to a failure mode you are experiencing. Are the PMs causing the failure
or addressing it? If they aren’t addressing and reducing failures,
then they add no value.
6. Then, believe in the outcome of your PME. If it says a PM adds
value, do it! If it shows it doesn’t, then re-write/re-engineer it so
it does, re-assign it to the appropriate PdM Technologies or get
rid of it! See the chart below. This process frees up resources for
use in proactive maintenance.
What to do about the problem?
Figure 1: PM Labor Hours vs. Emergency Labor Hours
Have you ever heard of “killer PMs”? These are PMs which are intrusive and are known to quite commonly cause premature failure
of an asset. One such example might be taking a pump out of service to inspect coupling shaft alignment. Consider carefully that
this inspection could be easily performed using infrared thermography or vibration analysis without shutting down the pump. Have
you ever seen someone lubricate an electric motor with sealed
bearings? These PMs
sound unnecessary.
Yet these things happen every day.
PMs can also absorb resources which
could be used for
work that would actually improve your
reliability.
Remember, the challenge of
Figure 2: Is this happening to you?
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Figure 3: PF Curve
In the graphic above, it is important to notice that Predictive
Maintenance allows one to detect a defect closer to “P” than Preventive Maintenance. We call this on-condition monitoring.
Do you realize that most Preventive Maintenance programs have
not been engineered, they have just evolved? With every regulation or component failure, both the number of PM tasks and the
frequency of the tasks being executed increases, until it consumes
30%–50% of your workforce and you are lulled into the false sense
Striking the right balance of Preventive and Predictive Maintenance is absolutely necessary and it offers a rare opportunity to
save millions of dollars through:
• Lower maintenance costs
• Lower spare parts inventories
• Lower energy consumption
• Better safety performance
• Increased throughput capacity
Achieving these results is not easy. For starters, you need to
have a common vision, a basic implementation strategy, and a
clear understanding of what’s required for success. Let’s look at the
four most important steps you can take to begin achieving your
reliability goals.
1. Receive training in PM/PdM Best Practices.
2. Update your functional hierarchy so that you have a clear understanding of the machines in your facility and their component configuration.
3. Conduct a criticality assessment on your assets. This assessment is used to help determine maintenance strategy, prioritize work orders, and make better overall risk management decisions. (Send me an e-mail if you would like more information
on this topic.)
Figure 6: Example of a PM Evaluation Sorting Exercise
If a company is not seeing results from their current PM Program
then it is time to change. Make it happen today. If you would like a
one-hour webinar on the topic send me an e-mail at rsmith@gpallied.com. I also have a Tool Box Training Session on Failure Modes
Driven Strategy you may enjoy. Just let me know if you are interested. Make something happen!
Ricky Smith, CMRP, CPMM, is the Senior Technical
Advisor for Allied Reliability. Ricky has over 30 years in
maintenance as a maintenance manager, maintenance
supervisor, maintenance engineer, maintenance training
specialist, maintenance consultant and is a well known
published author. www.gpallied.com
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