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What
Is Root Cause Failure Analysis?
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Written
by Robert J. Latino
AISE
Expo - May 1998
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Root Cause Failure Analysis or RCFA as it is sometimes called, tends to
have a different meaning depending upon who you ask. To put it simply,
it is a method or series of actions taken to find out why a particular
failure or problem exists and correcting those causes. It is similar to
what detectives do when a crime occurs or what the NTSB does when an airplane
crashes. |
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Let?s talk a little about why you would want to conduct a Root Cause Failure
Analysis in the first place. It is a proven fact that most of the failures/problems
that plague industry are what we would call CHRONIC. This means that they
happen more than once for the same reason. Furthermore, out of all of the
CHRONIC failures that you experience in a given year, 20% of those failures
represent 80% of the loss. These are important facts to understand when
you think about the benefits of Root Cause Failure Analysis. It means that
if you investigate the 20% of the failures representing 80% of your losses,
you will reap quantum benefits in a short period of time. We call these
few failures the "Significant Few" failures. |
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Once we have identified the "Significant Few" failures, we must begin analyzing.
While there are many ways to go about this, I would like to talk about
a process that has been successfully field tested over a 30 year period.
This process is called PROACT?. PROACT? is an acronym for the following: |
PReserving
Failure Data
Ordering
the Analysis
Analyzing
the Data
Communicating
Findings & Recommendations
Tracking
for Success
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Let?s take a look at each of these steps in greater detail: |
| Preserving
Failure Data |
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With any failure or problem it is of the utmost importance to collect data
with respect to that problem. Consider what an NTSB investigator does right
after an airplane crash. They comb the area for data such as the data flight
recorder ("black box"), broken airplane parts, instrument readings, etc.
You must do the same when you are analyzing a problem. We have a data collection
procedure called the 5P?s. The 5P?s are the categories of information necessary
to collect to begin analyzing a failure. The 5P?s stands for People, Parts,
Paper, Position and Paradigms. As an analyst, you must, through interviews,
brainstorm with all of the people involved to collect the other items based
on these 5 categories. |
| Ordering
the Analysis |
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It would be difficult to analyze any problem by yourself and it would be
unrealistic to think you could analyze a "Significant" problem without
the assistance of a multi-disciplined group of individuals. Ordering the
analysis consists of putting the right expertise on your team. You need
a Principal Analyst to facilitate your Root Cause Failure Analysis project
and a team of analysis experts. In addition to this team of experts, you
need to delineate exactly what your team charter or objective is. This
creates focus for the team. The team must also delineate exactly what rule
or guideline they will follow while analyzing this problem. We call these
critical success factors or CSF?s for short. |
| Analyzing
the Data |
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Once you have assembled your team and have collected the critical data,
you must now begin to analyze the problem. PROACT? uses a logic tree process
to help the team members focus on the problem at hand. They break the problem
down to it smallest components and then begin hypothesizing as to what
the underlying causes might be. The logic tree is broken down to 5 basic
steps: |
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Stating the Failure Event
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Stating the Failure Modes
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Hypothesizing
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Verifying Hypotheses
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Determining Underlying Causes
(Physical, Human and Latent)
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The team asks a series of "How Can" questions to come up with their hypotheses.
For instance, if our failure mode is a failed bearing our hypotheses might
be fatigue, overload, corrosion and erosion. We then have to use real field
data to prove or disprove the analysis team?s hypothesis. Once all hypotheses
have been proven or disproved we can assess which underlying causes are
physical, human or latent. These are the three main categories of problem
or failure causes. The logic tree is really a visual brainstorming tool
to help you logically figure out the root cause of a problem. |
| Communicate
Findings and Recommendations to Decision Makers |
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Once you have successfully completed the search for causes with your logic
tree, it is now time to communicate your findings and solutions to the
decision-makers. You must provide a detailed report to help the decision-makers
understand the effectiveness of your failure analysis so that your recommendations
are given a fair assessment. You must create such a compelling case that
it would seem foolish not to go ahead with your recommendations. |
| Tracking
for Results |
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Assuming that your communication with the decision-makers was successful,
you must now track the effectiveness of your recommendations to make sure
that you are getting the return on investment that you have anticipated.
You can do this with a number of measurements such as reduced maintenance
costs, improved production rates, reduced failure rates, etc? |
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What does all this mean to you? Reliability Center, Inc. clients who successfully
apply the PROACT? methodology have captured returns in excess of 800% to
1000%. These numbers may sound unrealistic, but think about what failures
cost the average manufacturing facility. In a typical oil refinery or other
continuous process plant, downtime costs can be staggering. Add in the
cost of the repair itself and we?re talking hundreds of thousands to millions
of dollars in a given year. Also remember that these failures are chronic,
so if we do not eliminate them they WILL happen again. |
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RCI offers a number of products and services to assist you in your endeavor
to begin analyzing failures. We have training
courses designed to teach engineers and technical representatives the
methods necessary to analyze and eliminate the "Significant Few" failures.
We also offer training that gives your operators and craftspeople the tools
necessary to identify, analyze and eliminate failures that they come in
contact with every day while still performing their normal job functions. |
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In addition to training, RCI has a proven track record of assisting clients
with Root Cause Failure Analysis facilitations. This simply means that
we work with your team for several days to get them off to a successful
start. From there we consult with the team to help them eliminate any roadblocks
that might prevent progress. |
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RCI has recently released PROACT?
software, to greatly enhance the effectiveness and efficiency of all Root
Cause Failure Analysis teams. PROACT?
is a software tool to help manage the Root Cause Failure Analysis process.
It provides the forms for data entry, a built in logic tree with integrated
verification logs, a reporting system to make communicating your results
a cinch. Last but not least, there is a tracking module to track key metrics
to make sure the recommendations that are implemented are providing the
required return. Isn?t it about time you started eliminating your "Significant
Few" failures? |
RCI Offers the full
range of Reliability Consulting Services and Training Programs for Industry.
We conduct facilitations, reliability assessments, FMEA & Root Cause
Failure Analysis Training - Public & On-Site.
For more information
contact:
Reliability Center, Inc.
P.O. Box 1421
Hopewell, Virginia 23860
Phone: (804) 458-0645
Fax: (804) 452-2119
Website: http://www.reliability.com
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