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FMEA
What is FMEA?
A systemized group of activities designed to:▪ recognize and evaluate the potential failure of a product/process and its effects▪ identify actions which could eliminate or reduce the chance of potential failure▪ document the process
Failure Mode and Effect Analysis
Failure Mode and Effect Analysis
Simply put FMEA is:a process that identifies all the possible types of failures that could happen to a product and potential consequences of those failures.
FMEA TermsFailure mode - the way in which
something might fail
Effects analysis – studying the consequences of the various failure modes to determine their severity to the customer.
Why do an FMEA?Preventing problems is cheaper
and easier than cleaning them up.Some things are too risky or costly
to incur mistakes.
The Reasons for FMEA Get it right the first time Indentifies any inadequacies in the
development of the product Tests and trials may be limited to a few
products Regulatory reasons Continuous improvement Preventive approach Team building Required procedures
FMEA Provides the Potential to:
Reduce the likelihood of customer complaints
Reduce the likelihood of campaign changesReduce maintenance and warranty costsReduce the possibility of safety failuresReduce the possibility of extended life or
reliability failuresReduce the likelihood of product liability
claims
Benefits Identify potential and known failuresReduce the number of engineering
changesReduce product development timeLower start-up costsGreater customer satisfaction Increased cooperation and
teamwork between various functionsContinuous improvement
History An offshoot of Military Procedure MIL-P-1629, titled
Procedures for Performing a Failure Mode, Effects and Criticality Analysis, dated November 9, 1949.
Used as a reliability evaluation technique to determine the effect of system and equipment failures.
Failures were classified according to their impact on mission success and personnel/equipment safety.
Formally developed and applied by NASA in the 1960’s to improve and verify reliability of space program hardware.
Concept FMEA Used to analyze concepts in the early
stages before hardware is defined (most often at system and subsystem)
Focuses on potential failure modes associated with the proposed functions of a concept proposal
Includes the interaction of multiple systems and interaction between the elements of a system at the concept stages.
Design FMEAAid in the objective evaluation of design
requirements and design alternativesAid in the initial design for
manufacturing and assembly Increase the probability that potential
failure modes have been consideredProvide additional information to aid in
the planning of efficient design testing
Process FMEA Indentify potential product related process
failure modes Assess the potential customer effects of the
failures Indentify the potential manufacturing
causes on which to focus on Develop a ranked list of potential failure
modes Document the results of the manufacturing
Types of FMEA
Resources NeededCommitment of top managementKnowledgeable individuals Individuals attentive to FMEA
timelinesPeople resources may be internal
or external to the business or a combination of both
FMEA TimingFMEA should be updated:
▪at the conceptual stage▪when changes are made to the design▪when new regulations are instituted▪when customer feedback indicates a problem
AdvantagesEnhance design and
manufacturing efficienciesAlleviate late change crisesMinimize exposure to product
failuresAugment business records Improve “bottom line” resultsAdd to customer satisfaction
LimitationsEmployee training requirements Initial impact on product and
manufacturing schedulesFinancial impact required to
upgrade design, manufacturing, and process equipment and tools
▪These limitations should be recognized and treated as short term and minimal interruptions to a business.
Risk Assessment FactorsSeverity (S): A number from 1 to 5, depending
on the severity of the potential failure mode’s effect 1 = no effect5 = maximum severity
Probability of occurrence (O): A number from 1 to 5, depending on the likelihood of the failure mode’s occurrence1 = very unlikely to occur5 = almost certain to occur
Risk Assessment FactorsProbability of detection (D): A number from 1 to 5,
depending on how unlikely it is that the fault will be detected by the system responsible (design control process, quality testing, etc.)1 = nearly certain detention5 = impossible to detect
Risk Priority Number (RPN): The failure mode’s risk is found by the formula RPN = S x O x D. RPN = Severity x Probability of Occurrence x Probability of Detection. RPN will be a number between 1 (virtually no risk) and 125 (extreme risk).
Procedures for FMEA
Necessity
“Process
Function”
Problem
“Failure Mode”
Effects How bad is it?
“Severity”
Causes How Likely?
“Occurrence”
Score Steps to
Prevent
Procedures for FMEA
Necessity
“Process
Function”
Problem
“Failure Mode”
Effects How bad is it?
“Severity”
Causes How Likely?
“Occurrence”
Score Steps to
Prevent
Put PB on bread
Procedures for FMEA
Necessity
“Process
Function”
Problem
“Failure Mode”
Effects How bad is it?
“Severity”
Causes How Likely?
“Occurrence”
Score Steps to
Prevent
Put PB on bread
No PB
Procedures for FMEA
Necessity
“Process
Function”
Problem
“Failure Mode”
Effects How bad is it?
“Severity”
Causes How Likely?
“Occurrence”
Score Steps to
Prevent
Put PB on bread
No PB Jelly Sandwich
Procedures for FMEA
Necessity
“Process
Function”
Problem
“Failure Mode”
Effects How bad is it?
“Severity”
Causes How Likely?
“Occurrence”
Score Steps to
Prevent
Put PB on bread
No PB Jelly Sandwich
5/5
Procedures for FMEA
Necessity
“Process
Function”
Problem
“Failure Mode”
Effects How bad is it?
“Severity”
Causes How Likely?
“Occurrence”
Score Steps to
Prevent
Put PB on bread
No PB Jelly Sandwich
5/5 Out of Stock
Past Expiration
Procedures for FMEA
Necessity
“Process
Function”
Problem
“Failure Mode”
Effects How bad is it?
“Severity”
Causes How Likely?
“Occurrence”
Score Steps to
Prevent
Put PB on bread
No PB Jelly Sandwich
5/5 Out of Stock
Past Expiration
2/5
Procedures for FMEA
Necessity
“Process
Function”
Problem
“Failure Mode”
Effects How bad is it?
“Severity”
Causes How Likely?
“Occurrence”
Score Steps to
Prevent
Put PB on bread
No PB Jelly Sandwich
5/5 Out of Stock
Past Expiration
2/5 10
Procedures for FMEA
Necessity
“Process
Function”
Problem
“Failure Mode”
Effects How bad is it?
“Severity”
Causes How Likely?
“Occurrence”
Score Steps to
Prevent
Put PB on bread
No PB Jelly Sandwich
5/5 Out of Stock
Past Expiration
2/5 10 Check Pantry
Check Expiration Date
Conduct an FMEAConduct a process FMEA on a
paper airplaneBuild a paper airplaneConduct a design FMEA on your
paper airplanePaper Airplane Competition
