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Our Goal : Zero Defect, Zero Breakdown
Our Goal : Zero Defect, Zero Breakdown
Root Cause Analysis
Content
1. Objective
2. Basic Approach
3. Example
Our Goal : Zero Defect, Zero Breakdown
Objective
• Zero Defect
• Zero Breakdown
• Zero Safety Risk
• Low Maintenance Cost
• Higher Productivity
• Effective Operability
• Low Variability
Our Goal : Zero Defect, Zero Breakdown
Approach
• A disciplined method using a logic tree
• A logic tree is required to represent
Cause and effect relationships
that lead to surfacing the undesirable event
Our Goal : Zero Defect, Zero Breakdown
Approach
What is the Logic Tree
What is the cause and effect relationship ??This will be explained in the coming slides during the presentation
A graphical way of representing Cause and effect relationship.
Our Goal : Zero Defect, Zero Breakdown
How to do the 5 - Why Analysis
Our Goal : Zero Defect, Zero Breakdown
How to do 5 - Y Analysis
Step 1:Step 1:• Identify the undesirable event and its
Important
• Facts are supported by some essence of
science, direct observation & documentation
with supporting factsassociated reason
Our Goal : Zero Defect, Zero Breakdown
Step 2:Step 2:
• Once identified the effect and reason.
• Find the reason as “ HOW” did it fail
Important
• Do not work out for assumptions.
• Only physical evidence, technical reason is
valid.
How to do 5 - Y Analysis
Our Goal : Zero Defect, Zero Breakdown
Note:Note:
•The facts cannot be hearsay or
assumptions !!
Evidence of MODE/ Reason
How to do 5 - Y Analysis
BUT Supported by
Our Goal : Zero Defect, Zero Breakdown
The End !!
Our Goal : Zero Defect, Zero Breakdown
If the above steps are so simple then…………...
Our Goal : Zero Defect, Zero Breakdown
If two guys are made to do the RCA of the same problem
WHY isPossibility of difference in the conclusions drawn by them
Our Goal : Zero Defect, Zero Breakdown
Where is the Gap ???
Our Goal : Zero Defect, Zero Breakdown
We need to explore the discipline necessary to provide consistency to our RCA Application
Thus Improving the credibility and
communication of the results
What is required to be done
Our Goal : Zero Defect, Zero Breakdown
How to improve credibility and communication of the results.
How to do it
Better Understanding
Use disciplinedthought process
to seek trueroot cause
We are not checkingthe thought process
that drew the conclusions
Impart training to bring a common understanding
into the process
Our Goal : Zero Defect, Zero Breakdown
Now let us do a 5 - Why analysis with an example
……….Hmmm undesirable Event
Our Goal : Zero Defect, Zero Breakdown
Sir, Pumpbearingfailed
Ask the fitter toChange it…. Pumpshould start now..
Our Goal : Zero Defect, Zero Breakdown
What was the problem
What did we do
What was to be done
What was the reason
Come on.. lets do the Root Cause Analysis
Our Goal : Zero Defect, Zero Breakdown
From Where do we start
Why did Pump Failed ??
Why did Bearing failed ??
OR
Getting Started…………..
Our Goal : Zero Defect, Zero Breakdown
Root Cause AnalysisRoot Cause Analysis1
First WhyFirst Why
Our Goal : Zero Defect, Zero Breakdown
When the event occurred, why was it brought to our attention
•Because the bearing failed
•Because the Pump FailedAnswer :
It was brought to our attention because
Therefore the last effect that caused us concern was the pump failure
One reason (MODE) that pump failed was
OR
due to bearing failure
the failed bearing caused a pump to stop pumping Oil.
From where should I begin…...
Our Goal : Zero Defect, Zero Breakdown
Evidence :
Answer
Thus we have
Event :Pump FailureMode : Bearing Failure (Supported by evidence)
Physically observed.
How can you say that it
failed because of bearing?
Objective Evidence
Our Goal : Zero Defect, Zero Breakdown
Effect
Reason
Pump Failure
Bearing failure
Logic Tree
WHY
Our Goal : Zero Defect, Zero Breakdown
Thus is any step of evaluation (first Why to 5 why)One is the effect and
Each reason is to be evaluated with
evidence to justify the reason
Other is reason(s)
Thus the relationship between the cause and effect lies with the
Evidence
Cause and Effect Relationship
Our Goal : Zero Defect, Zero Breakdown
Example :Bearing Failure caused a
pump to stop working.
• Last Effect is :
• Mode (reason)
:• Evidence of
Mode ( Reason)
- Pump Failure
- Bearing failed
- Physical evidence
Relationship
Cause and Effect Relationship
Our Goal : Zero Defect, Zero Breakdown
What is Evidence
It can be any clarification based on
• Technical Reasoning
• Physical Evidence• Supporting data viz..Asset care, Condition Appraisal, Log book etc
BUT CANNOT BE BASED ON ASSUMPTIONS
Our Goal : Zero Defect, Zero Breakdown
Learning from this
For any undesirable event (Effect) …..there is one or more reason(s) And we need to hunt them down
For any reason (mode) / Cause we find…..we need to justify it
With a objective evidence
Cause / Reason
EffectObjectiveEvidence
Cause Effect Relationship
Our Goal : Zero Defect, Zero Breakdown
MODULE MODULE 2
Second WhySecond Why
Our Goal : Zero Defect, Zero Breakdown
Often it happens we tend to conclude fasterwith our preset mind
Jumping to Conclusion
Our Goal : Zero Defect, Zero Breakdown
Why did the bearing Failed ??
Dear brother itfailed due to someforeign particle Entering in it
We perceive a problem to exist and we go right to what the most obvious cause is to US
Mind Set
No doubt we cannot deny this reason….but need to have an evidence
This is the FINISHED PRODUCT APPROACH
Our Goal : Zero Defect, Zero Breakdown
Finished Product Approach :
We perceive a problem to exist and we go the right to what the most obvious cause is TO US !!We do not validate any of our assumptions, we just assume a cause and spend money to implement a fix and hope it works
Experience shows this approach to beineffective and very expensive.
Our Goal : Zero Defect, Zero Breakdown
Now Let us find the Second why but in a different way ??
Our Goal : Zero Defect, Zero Breakdown
Why did the bearing Fail ??
Hmm…Erosion,Corrosion,Fatigue,Overload
For this we need to think we an open mind.At times we need to consult others
Mind Set
This is the DISCIPLINED THOUGHT PROCESS TO SEEK RESULT
WhyHow candid
Our Goal : Zero Defect, Zero Breakdown
Continuing our search backwards for the cause and effect relationships
We would then ask
How can a bearing fail ??
Our Hypothesis may be
Erosion, Corrosion, Fatigue, Overload
How can we prove which are true ( Evidence)
Note : We asked How can a bearing fail and not Why did a bearing fail
How can it fail -----this is brainstorming
Out of the various reasons you brainstormed, you look for the evidence.And then conclude…..bearing failed….why….due to…fatigue…evidence...
Our Goal : Zero Defect, Zero Breakdown
Search for Evidence
Hypothesis Verification Techniques
Erosion,Corrosion,Fatigue, Overload Metallurgical Analysis
High Vibration Vibration monitoring inst.
Misalignment Laser Alignment technology
While carrying out the investigation, metallurgical and physical test proved that it failed due to fatigue.
Our Goal : Zero Defect, Zero Breakdown
ErosionErosion
EffectReason
OverloadOverloadCorrosionCorrosion FatigueFatigue
Logic Tree
Pump Failure
Bearing failure
Why
How Can ??
Why
Our Goal : Zero Defect, Zero Breakdown
MODULE MODULE 3
Third WhyThird Why
Our Goal : Zero Defect, Zero Breakdown
You can now see that as we develop new sets of hypotheses, we are proving what we say at each level of the process.
This is demonstrating quality of process.When we continue this reiterative process, we are validating our conclusions each step of the way.
This way, when we draw our conclusions about root causes, they will be right because we have supported them based on fact and not mere assumption.
Our Goal : Zero Defect, Zero Breakdown
Logic Tree
ErosionErosion
Effect
Pump Failure
Bearing failure
OverloadOverloadCorrosionCorrosion FatigueFatigue
Reason High Vibration
Evidence / Notes for clarification: Asset Care Check list states vibration was observed from past 5 days (PAST DATA)
Why
How Can ??
How Can ??
Our Goal : Zero Defect, Zero Breakdown
MODULE MODULE 4
Fourth WhyFourth Why
Our Goal : Zero Defect, Zero Breakdown
When most people conduct their version of Root Cause Analysis (RCA),Where do they usually stop?How do they know they are done? How do they know that the problem will not reoccur?
These questions represent reality when we are the ones in the field working on a pressing problem with management on our backs.
If we consider ourselves manufacturing detectives, are we content with the stopping at the “HOWS” or the “WHYS”
Our Goal : Zero Defect, Zero Breakdown
Erosion
Pump Failure
Bearing failure
OverloadCorrosion Fatigue
Reason
Effect High Vibration
Logic Tree
ResonanceImbalance Misalignment
Why
How Can ??
How Can ??
How Can ??
Our Goal : Zero Defect, Zero Breakdown
MODULE MODULE 5
Fifth WhyFifth Why
Our Goal : Zero Defect, Zero Breakdown
Reason
Logic Tree
Effect
Pump Failure
Bearing failure
Why
Erosion OverloadCorrosion Fatigue
How Can ??
High Vibration
How Can ??
ResonanceImbalance Misalignment
How Can ??
ImproperToolsNo Procedures
Inadequate training
Why
Reason
Effect 1st Why2nd Why
Effect
Rot cause analysis
Root Cause Analysis
Reason
Rot cause analysis
3 rd Why
Reason
4 th Why
Root Cause Analysis
5 th Why
Effect
Reason
Root Cause Analysis
Effect Rot cause an
Our Goal : Zero Defect, Zero Breakdown
Now tell me when we typically
conduct analyses, are we more like a
engineer or the prosecutor and the detective looking to
win his case?
What is the difference between the those roles?
Our Goal : Zero Defect, Zero Breakdown
How to do it
Engr’s role is to determine with science HOW event
occurred ?Then what is the
role of prosecutor and detectives??
Yes !! they in essence will map out HOW
the crime occurred and be able to prove that it happened just
that way.
This means that a certain sequence of cause and effect
relationships linked up and resulted in the undesirable event.
Their role is to prove that each hypothesis did or did not occur.
Role of prosecutor
& detectives is typically to determine
WHY.
Our Goal : Zero Defect, Zero Breakdown
We should use our Technology to prove or disprove our
hypotheses and then explore Why people make decisions that result in the undesirable outcomes or
failure
Summary:
First WE must provide the HOW pieces of puzzle and then determine why decisions that lead to the undesirable outcome
Our Goal : Zero Defect, Zero Breakdown
Let us look at the example we studied……….
Our Goal : Zero Defect, Zero Breakdown
Logic Tree
Reason
Pump Failure
Bearing failure
Why
Erosion OverloadCorrosion Fatigue
How Can ??
High Vibration
How Can ??
ResonanceImbalance Misalignment
How Can ??
ImproperTools
No Procedures Inadequate training
Why
Effect
Reason
Physical
Human
Latent Latent Latent
Our Goal : Zero Defect, Zero Breakdown
The undesirable event is : pump failure
Hypothesis Verification Techniques
Erosion,Corrosion,Fatigue, Overload Metallurgical Analysis
High Vibration Vibration monitoring inst.
Misalignment Laser Alignment technology
We must understand the cause and effect relationships that lead to the event
These questions answer how??But what about why
This will require evidence to prove our hypothesis
Our Goal : Zero Defect, Zero Breakdown
In this case someone misaligned a pump and that decision resulted in a sequence of cause & effect relationship that caused the pump to fail prematurely.
Our Goal : Zero Defect, Zero Breakdown
Now the question is WHY would a person choose to align in that fashion !!
Our Goal : Zero Defect, Zero Breakdown
If we were to go deeper & understand
the thought process or the rational for such a decision (Latent Root),
we would uncover the REALROOT CAUSE.
I got it!!It means that either he was not trainedNo SOP available, tools worn out or inadequate
YES Exactly !!
Our Goal : Zero Defect, Zero Breakdown
If we do not explore the WHY,then HOW is likely to reoccur
Our Goal : Zero Defect, Zero Breakdown
If you now reflect on your current RCA efforts, do you stop at the how or at the WHY
Our Goal : Zero Defect, Zero Breakdown
Think about it……………….
Our Goal : Zero Defect, Zero Breakdown
Thank You !!