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Articles
> The RCM Trap
by
Christer Idhammar
Source:
Maintenance Management Consultants - Idcon This column is likely to create a lot of reactions from the academia
of reliability and maintenance, and all comments are welcome.
USING RCM WISELY. Reliability Centered
Maintenance (RCM) has its place, but many times mills jump into
training programs and attempt to implement this concept long
before they are ready for it. The academia of maintenance still
argue about the definition of RCM. Some even say that if it is
not done exactly the way they prescribe, then it is not RCM.
So what? The whole idea is that you want to achieve more cost-effective
reliability through the implementation of better operations and
maintenance practices.
RCM has its definite place in the specification and design phase of new equipment
and systems, and for existing critical and complicated systems. The thought
process used, for example, to analyze existing preventive programs, is good,
but can easily be made overcomplicated to serve the purpose. I have analyzed
the results of many RCM implementations, and the fact is that after a very
lengthy criticality and failure mode analysis, the end results have not changed
the fact that a V-belt drive needs to be inspected for an obviously critical
belt conveyor! What is often missing is a document describing how to inspect
it while the equipment is operating. In the worst cases, belts, couplings,
heat exchangers, control valves, and other common components are, even after
the RCM analyses, inspected during shutdowns. Perhaps some inspections have
been deleted because equipment was not critical. So, there you might have saved
an inspection that only takes two minutes for an operator who will inspect
the process in that area every shift anyway!
I suggest that before you enter into RCM you do the following:
- Do your maintenance prevention well;
- Do your basic inspections well;
- Do your predictive maintenance well.
The first two of the above activities are low cost and easy to implement
because of high acceptance by people in your organization. You can
use standard training material to train people when and how to do inspections.
What you do with, for example, a coupling, can be decided without a
complicated analysis. The failure developing period for misalignment
might be two to eight weeks, so you need to inspect it every week on
the run using an infrared thermometer. How to do this is described
in a Condition Monitoring Standard for each common component. (If you
would like to receive an example of a standard, please contact me.)
KNOWING THE BASICS. The time to implement
is short; a production area can have all inspections documented, people
trained, and inspections executed in less than four weeks. An RCM approach
and implementation could take six months with no different result.
An RCM analysis might lead you to spend days deciding that the primary
screen is critical, and that if the bearings fail the screen goes down;
therefore, you need to inspect the bearings—all of which is obvious.
RCM does not consider planning and scheduling and people efficiency at all,
nor does it include vital support systems such as a technical database and
its interface with stores. RCM is therefore a tool that should be used selectively
for critical and very complicated systems and equipment. It is not a complete
reliability and maintenance system. Do not fall into the trap of believing
it is something completely new and different, or that it is a complete program
for reliability and maintenance. I know mills that have spent over three years
on RCM implementation and they still do not have the basics in place and/or
executed well. It cannot be reinforced often enough to do the basics well before
you start complicating things.
Maintenance
Management Consultants - Idcon
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