Failure Mode and Effects Analysis (FMEA)

1. RME-085
Total Quality Management
Topic: Failure Mode and Effects Analysis (FMEA)
By:
Dr. Vinod Kumar Yadav
Department of Mechanical Engineering
G. L. Bajaj Institute of Technology and Management
Greater Noida
Email: vinod.yadav@glbitm.org

2. Failure Mode and Effects Analysis (FMEA)
Note: The contents used in this slide is being used for academic purposes only, and is intended only for students registered in B.Tech Mechanical Engineering at AKTU Lucknow in VIII
semester 2019-20, and is not intended for wider circulation.
- FMEA: Structured approach of
discovering potential failures that
may exist within the design of a
product or process [1].
- Failure modes: Ways in which a
process can fail.
- Effects: Ways that these failures can
lead to waste, defects or harmful
outcomes for the customer.
- Introduced in 1950.
- Highly effective method –
lowers the failure
FMEA aims: To anticipate failures during the design
stage by identifying all of the possible failures in a
design or manufacturing process.
Aerospace (NASA) – adopted in 1960
Automotive sector – 1970
QS 9000 – 1994 included FMEA concept
FMEA importance:
- Assessment of design /process failure modes.
- Evaluate the complexity of failure modes.
- Identify the causes of failures.
- Evaluate the probability of occurrence of failure modes.
- Identification of ways of controlling the Failure modes.
- Evaluation of risks associated with failure modes.
- Development of action plans for corrective measures.

3. Failure Mode and Effect Analysis categories
Note: The contents used in this slide is being used for academic purposes only, and is intended only for students registered in B.Tech Mechanical Engineering at AKTU Lucknow in VIII
semester 2019-20, and is not intended for wider circulation.
- FMEA categories: Design FMEA
(DFMEA)
Explores the possibility of product
malfunctions, reduced product life, and
safety and regulatory concerns derived from:
- Material Properties
- Geometry
- Tolerances
- Interfaces with other components
- Engineering Noise: environments, user
profile, degradation, systems interactions.
- FMEA categories: Process FMEA
(PFMEA).
- Explores failure that impacts product
quality, reduced reliability of the process,
customer dissatisfaction, and safety or
environmental hazards derived from:
- Human Factors
- Methods followed while processing
- Materials used
- Machines utilized
- Measurement systems impact on acceptance.
- Environment Factors on process
performance.

4. Process FMEA
Note: The contents used in this slide is being used for academic purposes only, and is intended only for students registered in B.Tech Mechanical Engineering at AKTU Lucknow in VIII semester 2019-20,
and is not intended for wider circulation.
Describe
process (Flow
diagram,
customer need
etc.)
Describe
functions
(Enlist
functions)
Identify
potential
failures /
failure modes
Calculate risks
(RPN = S*O*D)
Take corrective
actions
(Reduce S, O and D)
Evaluate results
Severity
(S)
Occurrence
(O)
Detection
(D)
Specific loss of function, process, part etc.
Describe
effects of
failures
(Consequences)
Find causes of
failure
(using RCA)
Adapt suitable
controls
(Mechanism,
modes, methods,
tests to prevent
failure cause)

5. Risk Priority Number (RPN) = S*O*D
FMEA approach to identify problem:
1. Severity (S) of the effect on the customer (Severity rating is the effect of the failure on the rest of the system
if the failure occurs).
2. Occurrence (O) and frequency of problem
3. Problem Detection (D) easiness.
Score matrix rating: 1-10 scale.
Severity
1 2 3 4 5 6 7 8 9 10
Low risk High risk
1 2 3 4 5 6 7 8 9 10
1 2 3 4 5 6 7 8 9 10
Low probability of risk
Likely catch a failure
High probability of risk
likely not catch a failure
Occurrence
Detection

6. Note: The contents used in this slide is being used for academic purposes only, and is intended only for students registered in B.Tech Mechanical Engineering at AKTU Lucknow in VIII
semester 2019-20, and is not intended for wider circulation.
Calculation of Risk Priority Number (RPN) = S*O*D
Table 1: S, O, D ratings [2]
Rating Severity (S) Occurrence (O) Detection (D)
10 Hazardous without warning Very high failure (almost inevitable) Absolute uncertainty
9 Hazardous without warning Very high failure (almost inevitable) Very remote
8 Very High High repeated failures Remote
7 High High repeated failures Very low
6 Moderate Moderate occasion failure Low
5 Low Moderate occasion failure Moderate
4 Very low Moderate occasion failure Moderately high
3 Minor Low: relatively few failures High
2 Very Minor Low: relatively few failures Very high
1 None Remote failure is unlikely Almost certain

7. Closing comments about FMEA
Failures and defects are expensive !!
If defects in products and services are detected through rigorous testing and
predictive modelling in the later stages – may add significant cost.
FMEA: Technique that helps organizations to identify potential failures during the
design stage by enlisting all possible modes of failures in a design or
manufacturing process.
Role of FMEA
- Discover failure at its earliest point in product or process design
- Beneficial at design phase of product, process or service
- For continuous improvement
- Reduces failures
Note: The contents used in this slide is being used for academic purposes only, and is intended only for students registered in B.Tech Mechanical Engineering at AKTU Lucknow in VIII
semester 2019-20, and is not intended for wider circulation.

8. References:
[1] https://quality-one.com/fmea/ (Accessed on 20.04.2020)
[2] https://www.researchgate.net/figure/Severity-occurrence-and-detection-rating-scales-6_tbl1_322521755 (Accessed on
21.04.2020)

9. Thank you