Maintworld 4/2016

RELIABILITY
Various Components of ACR.
categories are not equal. For example,
the most extreme consequence from a
safety point of view could be a fatality,
whereas from a maintenance point of
view it is the destruction of equipment.
Clearly a fatality is far worse. Therefore
it is recommended that you scale or
weight each of the consequence categories
so that when each of the category
experts assign a score they will be normalized.
ASSET CRITICALITY
RANKING WILL REVEAL
WHICH ASSETS HAVE A
HIGH RANKING DUE TO POOR
RELIABILITY.
the severity of the consequences of failure
- that may reveal issues that need to
be addressed in order to mitigate those
risks, for example adding redundancy so
production can’t be affected.
A Living System
It is important to understand that this
is not a task that is performed once and
forgotten. As condition monitoring or
other detection systems are implemented,
the ranking should be updated. When
the reliability of assets is improved, the
ranking should be updated. If additional
measures are made that mitigates some
of the risks, for example improvements
in spares management, the ranking
should be updated. And as new assets
are installed, and old assets a retired, the
criticality ranking should be updated.
Conclusion
There is so much more that could be discussed
in relation to this topic, but that is
what training is for. It is hoped that this
article will clarify the importance of the
asset criticality ranking and provide you
with a practical approach to developing
the ranking.
What Do You Do With The Asset
Criticality Ranking?
The good news is that you can basically
do two things with the ranking that you
have defined.
First, as mentioned in the introduction,
you can use the ranking to help you
make important decisions. It is always
important that everything you do adds
value to the business. If you have defined
the asset criticality ranking process correctly,
the assets that achieve the highest
score will have the greatest impact on
your business should they fail, and therefore
that is where you should focus your
attention.
Second, if you record all of the values
for reliability, detectability, and consequence
as described above, then you
have a wealth of information that you
can use to refine the decisions you have
to make. The asset criticality ranking
will reveal which assets have a high ranking
due to poor reliability - they will be
good targets for reliability improvement
projects. It will reveal where assets have
a high criticality due to lack of detectability
- that is a good place to implement
condition monitoring. And it will reveal
where you have high criticality due to
The final score sheet could look like the following chart.
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