FMEA
Outline
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What is FMEA?
History
Timing
Benefits
Applications
Stages of FMEA
FMEA Team
Procedure (RPN=S*O*D)
Summary
What is FMEA?
• FMEA stands for Failure Mode
and Effect Analysis
• Methodology of FMEA:
– Identify the potential failure of a
system and its effects
– Assess the failures to determine
actions that would eliminate the
chance of occurrence
– Document the potential failures
What is FMEA
FMEA is a systematic way of
assuring that every conceivable
potential failure of a
design/process has been
considered.
History of FMEA
• Created by the aerospace
industry in the 1960s.
• Ford began using FMEA in 1972.
• Automotive Industry Action
Group and American Society for
Quality Control copyright
standards in 1993.
Timing
• Integral part of the early design
evaluation
• During the design phase
• Preliminary design or layout
• Design improvement
programmes
• Perriodically updated
What are the Benefits?
• Improvements in:
– Safety
– Quality
– Reliability
Benefits
• What other potential benefits
can be identified?
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Company image
User satisfaction
Lower development costs
Presence of a historical record
Applications
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Concept
Design
Process
Service
Equipment
4 Stages of FMEA
• 1. Specifying Possibilities (ROOT
CAUSES/ EFFECTS)
• 2. Quantifying Risk ( SEVERITY,
OCCURENCE, DETECTION= RPN)
• 3. Correcting High Risk Causes
(DETAILING ACTION/ASSIGNING
RESPONSIBILITIES)
• 4. Re-Evaluation of Risk (RECALCULATIING OF RPN)
FMEA Team
• It is a team effort
RESPONSIBILITIES
Determining the meeting time and place
Communicating
Coordinating
Corrective Action/Assignments
Follow up
Participation from all
Keeping the records/files/documents
Keeping the process moving
FMEA Procedure
• Assign a label to each system
component
• Describe the functions of each
part
• Identify potential failures for
each function
Procedure
• Determine the effects of the
failures
• Estimate the severity of the
failure
• Estimate the probability of
occurrence
Procedure cont.
• Determine the likelihood of
detecting the failure
• Determine which risks take
priority
• Address the highest risks
– Assign a Risk Priority Number
• Update the FMEA as action is
taken
FMEA Flow Chart
Assign a label to each process or system component
List the function of each component
List potential failure modes
Describe effects of the failures
Determine failure severity
Determine probability of failure
Determine detection rate of failure
Assign RPN
Take action to reduce the highest risk
SEVERITY
• Severity is an assessment of the
seriousness of the effect and
refers directly to the potential
failure mode being studied
OCCURENCE
• The occurrence is the
assessment of the probability
that the specific cause of the
failure mode will occur
DETECTION
• This is an assessment of the
probability that the proposed
process controls will detect a
potential cause of failure or a
process weakness
Ranking for SEVERITY
Rank
1
2
3
4
5
6
7
8
9
10
Effect
None
Very Minor
Minor
Very Low
Low
Moderate
High
Very High
Hazard with Warning
Hazard without Warning
Ranking of OCCURENCE
Rank
1
2
3
4
5
6
7
8
9
10
Evaluated Failure Rates
1
1
1
1
1
1
1
1
1
1
in
in
in
in
in
in
in
in
in
in
1,500,000
150,000
15,000
2,000
400
80
20
8
3
2
Ranking of DETECTION
Rank
1
2
3
4
5
6
7
8
9
10
Detection
Almost Certain
Very High
High
Moderately High
Moderate
Low
Very Low
Remote
Very Remote
Almost Impossible
RPN (RISK PRIORITY
NUMBER)
RPN =
SEVERITY*OCCURENCE*DETEC
TION (S*O*D)
Value Ranges from 1 to 1000, 1
being the smallest possible risk.
FMEA Worksheet
Summary
• FMEA is a procedure designed to
identify and prevent potential
failures
• Provides cost savings and
quality enhancing benefits
• Should be used for all business
aspects in both manufacturing
and services
THANK YOU