The document discusses Failure Mode and Effect Analysis (FMEA), including its objectives, history, benefits, limitations, and how to conduct one. An FMEA is a process that identifies all possible failures in a service or process, assesses their effects and risks, and prioritizes actions to reduce risks. It was first used in the aerospace industry in the 1960s and has since been adopted by other industries like automotive. Conducting an FMEA involves a team identifying failure modes, effects, causes, controls, and risk levels to develop corrective actions.
3. Failure Mode and Effect Analysis
FMEA is:
a process that identifies all the possible
types of failures that could happen to a
service and potential consequences of
those failures
4. FMEA
A structured approach to:
Identifying the ways in which a process can fail
Estimating risk associated with specific causes
Prioritizing the actions that should be taken to
reduce risk
Evaluating design validation plan (design FMEA)
or current control plan (process FMEA)
5. History of FMEA
First used in the 1960’s in the Aerospace
industry during the Apollo missions to check
the space hardware
In 1974, US Navy developed MIL-STD-1629
regarding the use of FMEA
In the late 1970’s, the automotive industry
was driven by liability costs to use FMEA
Later, the automotive industry saw the
advantages of using this tool to reduce risks
related to poor quality
6. What Is A Failure Mode?
A Failure Mode is:
Things that could go wrong
The way in which the steps and / or the
process could fail to perform its intended
function
Failure modes may be the result of upstream
operations or may cause downstream
operations to fail
7. Why should we use FMEA
Methodology that facilitates process improvement
Improve internal and external customer
satisfaction
Focuses on prevention
FMEA may be a customer requirement
Identifies and eliminates concerns early in the
development of a process or design
FMEA may be required by an applicable
Quality Management System Standard (CBAHI)
8. The Reasons for FMEA
Get it right the first time
Indentifies any inadequacies in the development
of the process
Continuous improvement
Preventive approach
Team building
Required procedure from regulatory bodies
9. FMEA Terms
Failure 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
10. Process FMEA
Indentify potential failures related to process
failure modes
Assess the potential customer effects of the
failures
Identify the potential causes on which to focus on
Develop a ranked list of potential failure modes
Document the results
11. FMEA Procedure
11
1. For each process input (start with high value inputs),
determine the ways in which the input can go wrong
(failure mode)
2. For each failure mode, determine effects
Select a severity level for each effect
3. Identify potential causes of each failure mode
Select an occurrence level for each cause
4. List current controls for each cause
Select a detection level for each cause
Process Steps
12. FMEA Procedure (Cont.)
12
5. Calculate the Risk Priority Number (RPN)
6. Develop recommended actions, assign responsible
persons, and take actions
Give priority to high RPNs
MUST look at severities rated as 10
7. Assign the predicted severity, occurrence, and
detection levels and compare RPNs
Process Steps
13. FMEA: A Team Tool
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A team approach is necessary.
Team should be led by the Process Owner
who is the technical person, or other similar
individual familiar with FMEA.
The following should be considered for team
members:
– process leaders
– process employees
– QM professional
Team Input
Required
14. Risk Assessment Factors
Severity (S): A number from 1 to 10, depending on the
severity of the potential failure mode’s effect
1 = no effect
10 = maximum severity
Probability of occurrence (O): A number from 1 to 10,
depending on the likelihood of the failure mode’s
occurrence
1 = very unlikely to occur
10 = almost certain to occur
15. Risk Assessment Factors
Probability of detection (D): A number from 1 to 10,
depending on how unlikely it is that the fault will be
detected by the system responsible (process control)
1 = nearly certain detention
10 = 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 1000 (extreme risk)
17. Risk Priority Number (RPN)
17
RPN is the product of the severity, occurrence,
and detection scores.
Severity Occurrence Detection RPNRPNX X =
Calculating a
Composite
Score
18. The FMEA Form
18Identify failure modes
and their effects
Identify causes of the
failure modes
and controls
Prioritize
Determine and
assess actions
A Closer Look
28. Summary
28
An FMEA:
Identifies the ways in which a process can fail
Estimates the risk associated with specific causes
Prioritizes the actions that should be taken to
reduce risk
FMEA is a team tool
Key Points
Hinweis der Redaktion
Our objectives for this class is for each person to be knowledgeable of the following things:
What is FMEA?
Why is an FMEA important?
History of FMEA
Benefits of FMEA
Limitations of FMEA
How to conduct an FMEA?
Simply put an FMEA is:
a process that identifies all the possible types of failures that could happen to a product and potential consequences of those failures.
The Failure Mode is what could go wrong and
The Effect Analysis is how it would happen; how likely is it to go wrong; how bad would it be
There are many reason to do an FMEA, several of the reason were already mentioned and this is a list of other reasons that one would want top conduct an FMEA.
The main reason to do an FMEA is to identify any inadequacies in the product and to get it right the first time so that there are no costly mistakes later.
Failure mode - the way in which something might fail. For example, a car’s tire might fail by puncture from a sharp object. It might also fail from a blowout resulting from wear. Puncture and blowout are two of the many tire failure modes.
Effects analysis – studying the consequences of the various failure modes to determine their severity to the customer. Of the two tie failure modes we just talked about, the blowout is likely to have the most serious consequence, since when a tire suddenly explodes the speeding car usually goes out of control, often with dire consequences. On the other hand, a puncture problem usually allows the tire pressure to decrease gradually, allowing the driver time to sense the problem before he looses control. Neither failure mode is something the driver wants but of the two the puncture is preferred.
A process FMEA is used to identify potential process failures and it assess the potential customer effects.
These are the risk assessment factors used in an FMEA.
Severity is a rating of how severe the failure would be.
Probability of Occurrence is a rating of how likely it is to happen.
The probability of detection is a rating on how likely it is to detect the failure
And the risk priority number is found by multiplying the severity rating by the probability of occurrence by the probability of detection.
The auto industry says that a risk priority number of 75 is acceptable. Anything more than that is unacceptable.
These flow charts are a visual on how to obtain the risk priority number.
The risk priority number is found by multiplying the severity rating by the probability of occurrence by the probability of detection.
It is important to know what an FMEA looks like. You want to gather all your smart people together. The process is tedious, time consuming and exhausting. The FMEA process can be summed up in a special worksheet. We’ve created one to show the example of creating a peanut butter and jelly sandwich.
This is an example of a process FMEA. CLICK Our necessity of process function is to put peanut butter on the bread. Another function would be to put jelly on the bread. CLICK Next up is the problem or failure mode. My problem is that I have no peanut butter in my house. Peanut butter is essential to getting peanut butter on the bread. Other problems could be I don’t have a knife or I don’t have bread or my hands are not working or I cant open the jar. CLICK The effect of having no peanut butter is that I end up with a jelly sandwich rather than a peanut butter and jelly sandwich. CLICK The next column is how bad that is or the severity of the effect. Here I will use a 0 to 5 scale with 5 being the worst thing that could happen. In healthcare if a patient could die then that is obviously a rating of 5. I am giving this a high rating because if I have no PB then I have no PB and jelly sandwich. CLICK The next column is all the reasons why this happened. All the reasons why I don’t have peanut butter. It could be that I don’t have any in the pantry or that what I do have is expired. CLICK The next column is another rating on how likely this is to occur. At my house since I have kids that really like to eat PB I would rate this a 2 out of 5. CLICK Next we multiply the score of how likely something is to happen with the how bad it is or severity rating. And this creates a “Hazards Score” CLICK The next column is the steps to prevent this.
So who knows :
What is FMEA?
-to figure out everything that could go wrong and what can be done to keep those things from happening
Why is an FMEA important?
-It’s for procedures or inventions that would be very risky or very expensive to correct
History of FMEA
-designed by the military 60 years ago
Benefits of FMEA
-Identify potential and known failures
-Reduce the number of engineering changes
-Reduce product development time
-Lower start-up costs
-Greater customer satisfaction
-Increased cooperation and teamwork between various functions
-Continuous improvement
Limitations of FMEA
-There are employee training requirements.
-There may be an impact on product and manufacturing schedules
-And there is a financial impact due to upgrading a design, adjusting manufacturing, or needing new equipment and tools
How to conduct an FMEA?
-find severity rating
-find probability of occurrence
-find probability of detection
-find the risk priority number is found by multiplying the severity rating by the probability of occurrence by the probability of detection.