Fmea process la

Potential Failure Mode &
Effects Analysis FMEA
PROCESS FMEA
ISO TS 16949:2002 Lead Auditor Course

2
Course Objectives
• By the end of the course the
participant should be able to;
– Understand how to audit FMEA’s
process
identify the two types of FMEA’s
complete a Process FMEA for a project
understand how to determine the RPN
and its implication

3
Failure Mode and Effects Analysis
• ISO TS requires FMEA’s to be generated and
revised during the following stages;
– Advanced Product Quality Planning - before or at
design concept finalisation/prior to tooling for
production
– Design reviews
– As a result of customer complaints
– As as result of customer/field returns
• FMEA’s are LIVING DOCUMENTS

4
• What is an FMEA?
– An FMEA is a structured process used to
analyse design and/or process activities and
to assure that potential failure modes have
been addressed and effects analysed.

5
• An FMEA is a
team process not a
single person
process

6
• Benefits of FMEA’s
– 1. Utilises previous history and
associated failure modes to
assist in developing quality
products during design - better
understanding of the product

7
–2. An objective evaluation of the
design or process - not subjective.
It forces an organisation to
quantify

8
–3. Cost & time savings - The
process identifies potential
causes/mechanisms of failure
before they occur

9
– 4. Provides a system for
establishing design and
process improvements and
for identifying Special
Characteristics

10
• 5. A structured proactive system that
aims to provide for Customer
Satisfaction

11
• There are two types of FMEA’s
• 1. Design FMEA
– Cooling system for vehicle, spoiler assembly,
wiring harness etc..
• 2. Process FMEA
– Injection moulding, welding, assembling etc...

12
• Definition of a Design FMEA
– A design FMEA is a structured process
used by Design Responsible companies to
ensure, to the extent possible, that possible
failure modes and their associated causes
and mechanisms have been considered
during the design process.

13
• Examples of when Design FMEA’s may be used;
– A company may be responsible for the complete
design of the cooling system of a vehicle.
– A company may be responsible for designing a
complete trimmed seat assembly
– A company may be responsible for developing and
designing a material to reduce Noise and Vibration in a
vehicle

14
• Definition of a Process FMEA
– A process FMEA is a structured process
used by a manufacturing company to
identify potential failure modes and their
associated causes and mechanisms for the
manufacture and assembly of product.

15
• Examples of when Process FMEA’s
may be used;
– A company has been provided with all of
the technical information to manufacture;
• An injection moulded interior door handle
• A metal pressed bracket
• A family of fasteners

How to Complete a
Process FMEA

17
Process Failure Mode and Effects
Analysis
• How to complete a Process FMEA
1. FMEA number
• A number used for tracking and identifying the
Process FMEA
– GM -001A

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Analysis
– How to complete a Process FMEA
2. Item
• Enter the name and number of the system, sub-system
or component for which the process is being analysed
– Rear Decklid Spoiler 92078645

19
Analysis
3. Process Responsibility
• Indicate the OEM, department and/or group
which is responsible for the Process
– Spoiler Design Team

20
Analysis
4. Prepared by:
• Enter the contact details of the person
responsible for preparing the Process FMEA.
This is typically the Process/Product Engineer
– Max Smart

21
Analysis
5. Model Year(s)/Vehicle(s)
• Enter the intended model year(s) and vehicle
lines that will utilise and/or be affected by the
Process being analysed, if known
– WH 1999

22
Analysis
6. Key Date
• The key date is defined as the due date for the
Process FMEA. This date should not exceed
the scheduled start of production.
– July 1999

23
Analysis
7. FMEA Date
• This date is defined as the original date the
Process FMEA was compiled and the latest
revision date.
– June 5, 1998, August 10, 1999 Rev 8

24
Analysis
8. Core Team
• List the names of the responsible individuals
and departments who have participated in the
generation of the Process FMEA.
– AW, PS, JA, RK, MH

25
Analysis
9. Process/Function Requirements
• Enter the name of the process being analysed.
It is important to be as concise as possible. Use
the same terminology as per any reference
documents.
• Examples are;
trimming, vacuum forming, welding etc..

26
Analysis
10. Potential Failure Mode
• Enter the potential failure mode(s) for that
process. Examples of failure modes might be,
but are not limited to;
– Stressing, Burrs, Cracking, Burning, Flash,
Fails to open, Part leaking, bent, brittle,
worn, tool mark etc...

27
Analysis
11. Potential Effects of Failure
• What if the failure occurs, what are the potential
effects? These need to be written from the customers
perspective. This can mean the next operation or
machine, not just end customer.
• Examples
• inoperable, unsatisfactory appearance, noisy because
of vibration, uncomfortable, erratic operation, unable
to fit or locate etc...

28
Analysis
12. Severity
• Enter the severity rating as described in
Appendix 1. The severity is an assessment of
the seriousness of the problem

29
Analysis
13. Classification
• Enter the special characteristic symbol as per
customer requirements for any critical,
significant, major, safety or Key characteristic.
ISO TS Section II should define the type of
symbol required.
ISO TS requires that all special characteristics
are addressed during the FMEA stage.

30
Analysis
14. Potential Cause(s)/Mechanism(s) of
Failure
• Enter any potential reasons for these failures
– Examples are:
– Improper weld
– Part not mounted correctly before drilling
– Incorrect cycle time
– Inadequate gauging
– Human error, Fatigue, interaction..
– Tool worn

31
Analysis
15. Occurrence
– Enter the Occurrence as per Appendix 2.
The Occurrence is defined is the
probability or the likelihood that the
specific cause or mechanism will occur.
This may be based on previous field
history, similar products and experience

32
Analysis
16. Current Process Controls
• Enter the current Process verification/validation
activities that will assure the adequacy of the
Process
• Typical examples may be, SPC, gauging
error proofing etc...

33
Analysis
17. Detection
• Enter the detection probability as per Appendix
3. Detection is defined as the ability of the
proposed Process controls to detect any Process
weakness or potential failure.

34
Analysis
18. Risk Priority Number (RPN)
• The Risk Priority Number is defined as the
Severity multiplied by the Occurrence
multiplied by the Detection. The RPN is a
measure of the Process risk. The RPN will be
between 1 and 1000. It is the responsibility of
the group to define what a high RPN is and
take the appropriate actions.

35
Analysis
19. Recommended Action(s)
• When high RPN’s are established corrective
action should be incorporated with a focus on
reducing the Process risk

36
Analysis
20. Responsibility
• Enter the name of the person(s) or organisation
who has the responsibility for implementing the
corrective action(s). This should also include a
target date for completion.

37
Analysis
21. Actions taken
• Enter the effectiveness and the results of the
actions taken

38
Analysis
22. Severity
• Re-enter the severity rating as described in
Appendix 1. The severity is an assessment of
the seriousness of the problem.

39
Analysis
23. Occurrence
• Re-enter the Occurrence as per Appendix 2.
The Occurrence is defined as the probability or
the likelihood that the specific cause or
mechanism of failure will occur. This may be
based on previous field history, similar
products and/or experience.

40
Analysis
24. Detection
• Re-enter the Detection probability as per
Appendix 3. Detection is defined as the ability
of the proposed Process controls to detect any
Process weakness or potential failure.

41
Analysis
25. Resulting RPN
• Based on the corrective action, calculate the
RPN and record this result. If further action is
required repeat the corrective action steps in
order to reduce the RPN.

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Appendix 1 Severity rating for Process FMEA
Effect Customer Effect Manufacturing/Assembly Effect Ranking
Hazardous-
without
warning
Very high severity ranking when a potential
failure mode affects safe vehicle operation
and/or involves nonconpliance with
government regulation without warning.
Or may endanger machine or assembly
operator, without warning.
10
Hazardous
with
warning
Very high severity ranking when a potential
failure mode affects safe vehicle operation
and/or involves nonconpliance with
government regulation without warning
Or may endanger machine or assembly
operator, with warning
9
Very High Vehicle/item is inoperable, loss of primary
function
Or 100% of product may have to be
scrapped, or vehicle/item repaired in
repair dept with a repair time greater
then 1 hr
8
High Vehicle/item is operable, but at a reduced
level of performance. Customer very
dissatisfied.
Or product may have to be sorted and a
portion (less than 100%) scrapped, oer
vehicle/item repaired in the repair
department with a repair time between a
half hour to one hour.
7
Moderate Vehicle/item is operable, but
comfort/convenience items inoperbale.
Customer dissatisfied
Or a portion (less than 100%) of the
product may have to be scrapped with no
sorting, or vehicle/item repaired in repair
department with a repair time of less then
1 hour
6
Low Vehicle/item is operable, but
comfort/convenience items operbale at a
reduced level of performance
Or 100% of product may have to be
reworked, or vehicle item repaired off line
but does not fo to repair dept
5
Very low Fit and finish/squeak and rattle item does
not conform. Defect noticed by most
customers (greater then 75%)
Or the product may have to be sorted,
with no scrap, and a portion(less then
100%) scrapped.
4
Minor Fit and finish/squeak and rattle item does
not conform. Defect noticed by 50%
customers.
Or a portion (less then 100%) of the
product may have to be reworked with no
scrap, on line but out of station.
3
Very Minor Fit and finish/squeak and rattle item does
not conform. Defect noticed
bydiscriminating customers (less then 25%)
Or a portion (less then 100%) of the
product may have to be reworked with no
scrap, on line but in station.
2
None No discernable effect. Or slight inconvenience to operation or
operator, or no effect
1

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Appendix 2
Occurrence rating for Process FMEA
Probability of failure Possible failure rates Ppk Ranking
Very High - Persistent failures ≥ 100 per thousand pieces < 0.55 10
50 per thousand pieces ≥ 0.55 9
High - Frequent failures 20 per thousand pieces ≥ 0.78 8
Moderate - Occasional Failures 5 per thousand pieces ≥ 0.94 6
Low - Isolated failures associated with
similar processes
0.5 per thousand pieces ≥ 1.20 3
Low - Relatively few failures 0.1 per thousand pieces ≥ 1.30 2
Remote - Failure is unlikely. ≤ 0.01 per thousand pieces ≥ 1.67 1

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Appendix 3
Detection
rating for
Process
FMEA
Detection Criteria Suggested Range of
Detection Methods
Ranking
A B C
Almost
impossible
Absolute
certainty of non-
detection
X Cannot detect or is not checked 10
Very remote Controls will
probably not
detect
X Control is achieved with indirect
or random checks only
9
Remote Controls have
poor chance of
detection
X Control is achieved with visual
inspection only
8
Very Low Controls have
poor chance of
detection
X Control is achieved with double
visual inspection only
7
Low Controls may
detect
X X Control is achieved with SPC
charting methods
6
Moderate Controls may
detect
X Control is based on variable
gauging after parts have left the
station, or GO/NO GO gauging
performed on 100% of the parts
after the parts have left the
station
5
Moderately
High
Controls have a
good chance to
detect
X X Error detection in subsequent
operations, OR gauging
performed on setup and first
piece check
4
High Controls have a
good chance to
detect
X X Error detection in station, or
detection in subsequent
operations by multiple layers of
acceptance: supply, inspect,
install and verify. Cannot accept
discrepant part.
3
Very High Controls
almost certain
to detect
X X Error detection in-station
(automatic gauging with
automatic stop feature). Cannot
pass discrepant part.
2
Very High Controls
certain to
detect
X Discrepant parts cannot be made
because item has been error-
proofed by process/product
design
1
Inspection
Types
Inspection types
A = Error proofed
B = Gauging
C = Manual Inspection

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Auditing PFMEA’s
1. Is the PFMEA conducted by a cross functional
team?
2. Has the Key date been defined
3. Is it consistent with the customer’s PPAP date?
4. Does the organisation consider all of the elements
within the process flow chart?
5. Has the organisation defined what constitutes a high
RPN
6. Does the organisation follow the definition of a
high RPN

46
Auditing PFMEA’s
7. Are recommended actions completed prior to the
Key date
8. Do the sequence of dates make sense?
9. How are revisions recorded?
10. Does the organisation ensure the PFMEA is a living
document?
11. Verify the occurrence rankings are based on
objective evidence
12. Ensure the organisation is using the correct
rankings for Severity, Occurrence and Detection

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