Process Failure Mode and Effect Analysis
1. FMEA History 12.FMEA approach
2. Practical Situation of Production 13. Process flow of FMEA
3. Defects 14. Severity
4. Impact of defects 15. Occurrence
5. Cause of defects 16. Detection
6. Wasting our time for fixing of problems 17. Risk Priority Number (RPN )
7. Purpose of FMEA 18. Model PFMEA Format
8. What is FMEA 19. PFMEA Exercise
9. When to conduct FMEA 20. Advantage OF PFMEA
10. Types of FMEA 21. Practical tips for PFMEA
11. Steps in FMEA
FMEA History
It is first used in Aerospace Industry - Apollo Program in 1960 ‘s
Initial Automotive adoption in 1970 ‘s - frequent safety issues
Required by QS -9000 & Advanced product Quality Planning process
in 1994 – for all automotive suppliers.
Now its adopted by many other industries for safety concerns and
quality issues.
Practical Situation of production
Theoretical Plan :
Production
Part Receipt Assembly Customer satisfaction Profit Growth
Ok part
Practical situation :
Production NG Segregation & Customer
Lock down
Part Receipt Assembly part Defects rework complaints
DEFECTS
DEFECTS :
Physical , functional or aesthetic attribute of a product or service that
exhibits' the product or service failed to meet one of the desired specifications.
Examples of Defects :
Missing of child part
Part damage
Incomplete process
Missing of process
Color variation
Wrong part
Out of dimension specification
Variation in chemical and physical properties
IMPACT OF DEFECT
WHY DEFECT IS A PROBLEM :
Bad product will reduce company satisfaction and company reputation
Customer complaints , PPM and unexpected chargers from customer
Customer delivery commitment will fail
Some defects may cause safety issues to the operators
It will affect process yield during production
At final it will affect company growth and business
CAUSES FOR DEFECTS
1) Processing error :
process operation missed or not performed as per standard operating
procedure or work standards.
2) Poor procedure or standards
Setting
3) Set up error :
machines adjustments incorrectly
4) Machines
5) Non conforming materials
6) Human Mistakes
Wasting our time in fixing problems
We are fixing problems, not preventing them.
We have plenty of time to fix our problem but never enough time to
prevent by doing its right at the first time.
Purpose of FMEA
1) Follow methodology that facilitate process improvements.
2) Identify and eliminate concerns early in the development of process or
design.
3) To improve internal and external customer satisfaction.
4) Focus on preventive action.
5) FMEA may be customer requirement during initial development or
corrective action standardization for concern.
6) Finally FMEA is one of the requirement of Quality Management system
IATF 16949 ( Clause 8.3.4.4 – PPAP )
Purpose of FMEA
18 ELEMENTS OF PPAP
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
1. Design records
2. Authorized engineering change if any document
3. Customer Engineering approval if required
4. Design FMEA
5. Process flow Diagram
6. Process FMEA
7. Control plan
8. Measurement System Analysis studies
9. Dimensional Results
10.Record of results / Performance test results
11.Initial process studies
12.Qualified laboratory documentation
13.Appearance approval report ( AAR ) if applicable
14.Sample production parts
15.Master sample
16.Checking aids
17.Customer - Specific requirement
18.Part Submission Warrant ( PSW )
FMEA
FMEA – FAILURE MODE AND EFFECTIVE ANALYSIS
Is a systematic proactive method for evaluating a process to
identify where and how it might fail and to assess the relative impact of
different failures in order to identify the part of process that are most
in need of change.
It is also called as proactive tool or reliability tool
When to conduct FMEA
When designing :
New System
New Products
New Processes
WHEN ? New Machines
Before planning the improvement for the above
Prior to change in product design or process
When carry over designs are used for the new applications
Before specific hardware is selected or for manufacturing
TYPES OF FMEA
Four main types of FMEA :
1. System FMEA or Concept FMEA ( SFMEA OR CFMEA)
Focuses on how interaction among global systems might fail
2. Design FMEA (DFMEA )
Focuses on how product design might fail
3. Process FMEA ( PFMEA )
Focuses on how processes that make product might fail
4. Machinery FMEA ( MFMEA )
How machinery that perform the process might fail
STEPS IN FMEA
What it can do for us :
1) Identifies design or process related failure modes before they
happen.
2) Determines the Effects & Severity of this failure modes.
3) Identifies the Causes and Probability Occurrence of the failure
modes.
4) Identifies the Controls and their Effectiveness of failure modes.
5) Quantifies and prioritizes the risk number ( RPN ) associated
with failure modes.
6) Develop and document action plan which will reduce risk.
FMEA APPROACH
A team approach is necessary to conduct FMEA study.
Team should be led by the process owner who is the responsible
manufacturing engineer or technical person, or other similar Individual with
FMEA.
Team should be considered :
Process Engineers ( Team Leaders )
Design Engineers
Production engineers
Production Operators
Quality engineers
Purchase engineers
Maintenance engineers
Marketing / Sales engineers
Safety engineers
HR engineers
Suppliers ( If required )
Customers ( If required )
Process flow for FMEA
TOOL INTERACTION
Process steps
New / revised process
Process FMEA chart
Process Flow chart
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Pro Control plan chart m b
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s y nu
ss
tep rit
Ne io
w s k pr ls
/r is tro
ev R n
is o
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pr e dc
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Process flow for FMEA
Understand your
customer ends
Develop & evaluate
Product /Process
Develop and
Concepts
derive action
plan
Create an
effective FMEA
team
Determine the
“ Effects ” of Calculate &
Define the FMEA failure modes Assess risk
scope
Determine the Determine the Determine the
Determine
product / process failure mode of Cause of the
controls
functions functions failure mode
Four main types of FMEA
1)Severity
2)Occurrence
3)Detection
4)Risk Priority Number ( RPN )
FMEA SCORING
DEGREE SEVERITY OF EFFECTS RANKING
EXTREME May endanger machine or operator Hazardous without warning sign 10
FMEA SCORING
DEGREE SEVERITY OF EFFECTS RANKING
EXTREME May endanger machine or operator Hazardous with warning sign 9
FMEA SCORING
DEGREE SEVERITY OF EFFECTS RANKING
Very high Major disruption in production, loss of primary functions 100% Scrap major loss of talk time 8
FMEA SCORING
DEGREE SEVERITY OF EFFECTS RANKING
High Reduced primary functions performance Minor disruption, production requires repairs loss in talktime 7
FMEA SCORING
DEGREE SEVERITY OF EFFECTS RANKING
Moderate Loss of secondary functions performance Minor disruption, production requires repairs and minor 6
scrap rejections in production
FMEA SCORING
DEGREE SEVERITY OF EFFECTS RANKING
Medium Reduced secondary functions performance Minor disruption, production must be repaired 5
FMEA SCORING
DEGREE SEVERITY OF EFFECTS RANKING
Moderate Minor disruption, product repaired Use - As – Is Deposition 4
FMEA SCORING
DEGREE SEVERITY OF EFFECTS RANKING
Low Fit & finish item , Minor defects may be reprocessed on line 3
FMEA SCORING
DEGREE SEVERITY OF EFFECTS RANKING
Low Minor Non conformance may be reprocessed on line 2
FMEA SCORING
DEGREE SEVERITY OF EFFECTS RANKING
None No effect 1
Occurrence
Production Qty OK NG
Failure rate 1 1 1 1
Cpk <0.33
RISK FACTOR
10
Capability
Very high
DETECTION
Detection relates to the ability of current processes or controls to identify
a potential failure mode or its cause before it reaches the end customer or
user. It assesses how effectively existing systems can detect a failure, and
is a crucial factor in determining the overall risk associated with that
failure.
Detection is assessed using a ranking system, typically on a scale (e.g., 1-10).
Lower numbers indicate high detection capability (meaning the failure is likely to be
caught), while higher numbers indicate poor detection (meaning the failure is
unlikely to be caught)
RISK PRIORITY NUMBER
Weightage of the failure it will alert to take action, and reduce the risk to minimize
the impact of failure.
Severity x Occurrence x Detection = RPN
RPN Limits for corrective action :
> 80 is better
> 100 is poor
> 120 is not advisable
PFMEA Exercise
Case 1 - Initial entry / preparations
Case 2 - Update after finding issues / customer complaints
Case 3 - “
Case 4 - “
Case 5 - “
ADVANTAGE OF FMEA
Methodology that facilitates process
improvement
Identifies and eliminates concerns earlier in the
development of process
Helps us to identify how our process is likely to
fail
Prevents customer complaints ,defects and cost
of poor Quality
Improves internal and external Customer
satisfaction
PRACTICAL TIPS FOR FMEA
Do not try FMEA alone it’s a group activity.
FMEA preparation and review maybe a time consuming
process.
Periodic review to be done ( minimum once in 6 month ).
Activities are required for completion it is not just a paper
work activity.
Need training and coaching regarding PFMEA, Problem
solving technics, Poka yoke and other tools.
Debate issues for getting mutual conclusions.
https:// https://
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