DFMEA – Complete Guide for Design.pdf

1. DFMEA Definition
DEMEA Full Form - Design Failure Mode Effect Analysis
DEMEA (Design FMEA) it means design failure mode effect analysis. On other hand it is type of failure mode effect analysis that motive is to reduce the product failure.
DFMEA is an practical approach used in the design and product development phase to improve and maintain the quality of product and its research process.
For an Example: Design FMEA Process Sheet of a Ballpoint Pen.
Image Credit: @IQAsystem
2. Why we need to use Design-FMEA
Quality is very important for customer satisfaction, loyalty and future product purchases. Recent quality scandals involving many companies have shown that serious design issues can damage a company's reputation or harm its business.
Less serious design problems fail to satisfy customers, delay new product launches, and cost the company financially.
In new product projects, design errors are inadvertently made during the design and product development phases. Without DFMEA almost all errors were detected only during validation and trial production, some only after the start of production.
However, the costs of developing countermeasures in the later phase are much higher than in the previous phase. With DFMEA, countermeasures are considered to coincide with the onset of defects.
Design Failure and Countermeasure (Image Credit: @IQAsystem)
3. When will DFMEA be conducted
With DFMEA, organizations can ensure that all design requirements are fully met before production begins and maintain design quality later.
3.1. When to start
For new product designs, FMEA should start with product design before prototypes are produced.
3.2 Verification Time
The team must continually review and update the DFMEA document as the product changes:
Product design changes: Product changes can be a reason for a DFMEA review. In this case, you need to focus on the point of change and the points made.
Quality problems caused by product design: New internal defects or customer returns need to be reflected in the DFMEA to review and consider corrective action.
4. Who will do the DFMEA?
A good DFMEA should be carried out by a multifunctional team and led by a responsible product designer. The departments involved should include design, test analysis engineers, manufacturing, supplier quality, product quality, service, and logistics, among others.
Hierarchy for DFMEA Team Organization
5. How DFMEA is done
5.1 DFMEA Templates
First, a DFMEA template (also known as a DFMEA form) is required. Like other FMEA templates, the DFMEA template consists of two parts: the head and the body.
The header contains general information including but not limited to product name, product number, team member, project manager, customer, document number, and document version.
The body contains many columns with links. There are many different FMEA design templates that contain different column names. Multiple columns can be divided or combined, but there is no difference in meaning.
DFMEA

1. DFMEA – Complete Guide for Design
1. DFMEA Definition
DEMEAFull Form –Design Failure Mode Effect Analysis
DEMEA (Design FMEA) it means design failure mode effect analysis. On
other hand it is type of failure mode effect analysis that motive is to reduce the
product failure.

2. DFMEA is an practical approach used in the design and product development
phase to improve and maintain the quality of product and its research
process.
For an Example: Design FMEA Process Sheet of a Ballpoint Pen.
Image Credit: @IQAsystem
2. Why we need to useDesign-FMEA
Quality is very important for customer satisfaction, loyalty and future product
purchases. Recent quality scandals involving many companies have shown
that serious design issues can damage a company’s reputation or harm its
business.
Less serious design problems fail to satisfy customers, delay new product
launches, and cost the company financially.
In new product projects, design errors are inadvertently made during the
design and product development phases. Without DFMEA almost all errors

3. were detected only during validation and trial production, some only after the
start of production.
However, the costs of developing countermeasures in the later phase are
much higher than in the previous phase. With DFMEA, countermeasures are
considered to coincide with the onset of defects.
Design Failure and Countermeasure (Image Credit: @IQAsystem)
3. When will DFMEA be conducted
With DFMEA, organizations can ensure that all design requirements are fully
met before production begins and maintain design quality later.
3.1. When to start
For new product designs, FMEA should start with product design before
prototypes are produced.
3.2 Verification Time

4. The team must continually review and update the DFMEA document as the
product changes:
Product design changes: Product changes can be a reason for a DFMEA
review. In this case, you need to focus on the point of change and the points
made.
Quality problems caused by product design: New internal defects or customer
returns need to be reflected in the DFMEA to review and consider corrective
action.
4. Who will do the DFMEA?
A good DFMEA should be carried out by a multifunctional team and led by a
responsible product designer. The departments involved should include
design, test analysis engineers, manufacturing, supplier quality, product
quality, service, and logistics, among others.
Hierarchy for DFMEA Team Organization
5. How DFMEA is done
5.1 DFMEA Templates
First, a DFMEA template (also known as a DFMEA form) is required. Like
other FMEA templates, the DFMEA template consists of two parts: the head
and the body.

5. The header contains general information including but not limited to product
name, product number, team member, project manager, customer, document
number, and document version.
The body contains many columns with links. There are many different FMEA
design templates that contain different column names. Multiple columns can
be divided or combined, but there is no difference in meaning.
DFMEAStandard Nomenclature
1.Items: Item (component, part, assembly) of the product/partto be
analyzed. An element has one or more functions.
2.Function: Element function. A function has one ormore requirements
3.Requirements:Functional requirements. The requesthas one or more
potential failure modes.
4.Failure Mode: The way an item may fail to meet therequirements. The
cancellation policy has one or more potential implications.
5.Effects: Possible impact of a potential failure modeon functionality and
customers.
6.Severity (S): The number in the rating reflects themost severe potential
impact of a withdrawal regimen. Severity is rated on a scale of 1 to 10,
with 10 representing the greatest risk.
7.Class: A special product feature or high risk modeof damage.
8.Cause: The reason why the error occurred. Denial regimeshave one or
more possible causes.

6. 9.Preventive controls(in control methods): Design actions to prevent
potential causes from occurring.
10.Occurrence (C): The number in the rating reflectsthe probability of
damage. Events are rated on a scale of 1 to 10, with 10 being the most
likely event.
11.Detection control(in control method) Design actionsto detect the error
or the cause of the error, if any.
12.Detection (D):The number in the rating reflects thebest method for
controlling detection. Detection is rated on a scale of 1 to 10, with 10
being the worst detection ability.
13.RPN: (Short for Risk Priority Number) An indicationnumber for the
risk assessment process based on severity, incidence and detection.
Depending on the RPN and the S, O, D index, the responsible
team/person must decide on the corrective action required for each
failure mode. The RPN formula is: RPN = S x O x D
14.Action: Recommended action to eliminate or reducethe probable
cause of the failure.
15.Responsibilities: The individual or team/departmentthat must carry
out the recommended action.
16.Target Finish Date:The date the plan is finished.
17.Actual Completion Date:Actual Completion Date.
18.Severity: Re-evaluate the severity of the damage modeafter
corrective action
19.Occurrence: Reassess the probability of occurrenceafter corrective
action
20.Detection: Reassessment of detection ability aftercorrective action
21.RPN: Recalculation of risk priority number after correctiveaction
5.2 Meta data of FMEA design
The following documents should be considered as input resources for the
FMEA design team:

7. Block diagram (boundary diagram): A product block diagram shows the
physical and logical relationships between product components. Bar charts
can be used to identify the elements contained in a DFMEA.
Parameter Diagram (P): P diagram is a structured tool used to describe the
physics associated with the design features, input lists, outputs, controls, and
noise figures of the target.
Quality History: Can be used to find potential failure modes and confirm the
effectiveness of countermeasures in new designs.
Drawings, technical specifications: Can be used to define functions and
requirements.
Bill of Materials: List of components/parts of the product.
5.3 Steps to develop FMEA design
When everything is ready, the DFMEA team, templates and supporting
documents, you can start executing the FMEA design by following the 9 steps
below:
●Define product requirements
●Brainstorming mode for potential bugs
●Impact analysis
●Look for possible causes
●Describe current controls for possible causes
●Occurrence assessment / current status determination
●Calculate RPN and assess the risk
●corrective action plan
●RPN reassessment after corrective action

8. 5.4 DFMEA connection
DFMEA is not a stand-alone document in the product and process
development process. To ensure that your DFMEAs are consistent with each
other, the information in the DFMEA must be linked to the relevant information
in other documents:
PFMEA
The relationship between PFMEA and DFMEA may not be clear because they
have different purposes. While PFMEA focuses on processes, DFMEA
focuses on products. However, the following links should be kept:
●The product and process characteristics specified in the PFMEA must
match the relevant elements in the DFMEA.
●Sometimes the DFMEA and PFMEA fault regimes have the same
potential impact. The severity weights associated with the same effect
should be the same in PFMEA and DFMEA.
●Potential PFMEA failure regimes that result in product-related impacts
should be listed in the DFMEA Potential Failures. In contrast, a potential
failure mode in DFMEA caused by a process should appear in the
PFMEA Potential Failure Effect.
Design Verification Plans and Reports (DVP&R)
Project inspection plans and reports are plans and reports used to confirm
that a system, product, or component meets design requirements. At a
minimum, the DVP&R should have test items, criteria, procedures, and
sample sizes. DFMEA Prevention and Detection Controls are the input data
for the test items included in the Project Verification Plan.
6. Summary

9. The DFMEA must reflect the current state of the product design and is
therefore referred to as a living document. However, keeping DFMEA alive is
not easy. This is because of the complexity of DFMEA and its relationship to
other documents. Maintaining life in DFMEA is much easier if we use proper
DFMEA software like FMEA analysis.