Training FMEA

1© TLC, FMEA 42703

2© TLC, FMEA 42703

Purpose for CoursePurpose for Course

This Class was developed to meet the following instructional need:

Provide instruction in the principles and best practices associated with Failure Modes and Effects Analysis methodology.

611 Whitby Lane Brentwood, CA 94513 1-925-285-1847 FAX: 1-925-513-9450 [email protected]

3© TLC, FMEA 42703

AudienceAudience

Audience:

This class is designed for those individuals who work on various aspects of product development and manufacturing. It is assumed they come from many different backgrounds, disciplines, education levels and will be working on a variety of product and process areas across many departments of a company.

Prerequisites:

None

Time:

Course requires 8 hours of classroom instruction. Additional time may be needed to complete workshop activities.

4© TLC, FMEA 42703

Course ObjectivesCourse Objectives

As a result of the course the participant will be able to:

1. Understand the various types of FMEAs

2. Apply the basic steps for FMEA generation

3. Know when and how to apply FMEA to product designs and internal processes

4. Identify potential design or assembly issues which will impact customer product performance and yields

5. Prioritize and manage improvement opportunities from FMEA results

5© TLC, FMEA 42703

Course OutlineCourse Outline

Section I Introduction to FMEAHistory of FMEAThe FMEA method When should FMEAs be developed?Types of FMEAsBenefits

Section II FMEA PreparationDetermine scope and objectivesIdentify FMEA participantsOrganize and review relevant data

Section III FMEA GenerationDevelop process flow diagramIdentify potential failure modeDetermine effects of failure modesIdentify potential causes of the failureDetermine potential controls for causesDetermine current containment for failuresCompute RPNs for each potential failure

Section IV FMEA Action PlansPrioritize failure modesDetermine recommended actionsAssign ownersVerify effectiveness with new dataReview and update FMEA

6© TLC, FMEA 42703

FMEA IntroductionFMEA Introduction

Section I Introduction to FMEAHistory of FMEAThe FMEA method When should FMEAs be developed? Types of FMEAs

System DesignDetailed DesignProcessEquipment

BenefitsAnticipate problemsFix problems fasterImproved process controls

7© TLC, FMEA 42703

History of FMEAHistory of FMEA

Developed by NASA in the 1960's

Spread to many different industries:AutomotiveAerospaceElectronics PetrochemicalPharmaceutical Medical deviceSemiconductorAssembly and Test

Today FMEA is often a customer requirement

8© TLC, FMEA 42703

The FMEA Method and FlowThe FMEA Method and Flow

Action Plans

Potential Failure Modes

Potential Effects of Failure

Potential Causes of FailureSystem, Design, Process or Equipment Current Control(s) in Place

Current Containment in Place

9© TLC, FMEA 42703

FMEAFMEA

FMEA Objective, scope and goal(s):

Key Date: FMEA Type: DesignSystem: Potential FMEA Number:

Subsystem: Failure Mode and Effects Analysis (FMEA) Prepared By: Component: Design FMEA Date:

Design Lead: Revision Date: Core Team: Page: of

Action Results

Item / Function Potential Failure Mode(s)

Potential Effect(s) of Failure

Sev

Potential Cause(s)/

Mechanism(s) of Failure

Prob

Current Design/Process

Controls

DET

RPN

Recommended Action(s)

Responsibility & Target

Completion DateActions Taken

New

Sev

New

Pro

b

New

Det

New

RPN

SealsCoolant containment. Hose connection. Coolant fill. M

Sensor mount. Seal

Compression set Leak 8 Gasket material 7 Pressure cycle w/cold shock.

1 56 Use imported material

Sensor mount. Seal

Loosen during sensor assembly/service

Leak. Fall inside tank

8 Fitting not held in place

2 Added rib. 1 16 Implement holding rib in design. New fitting design. Prototype validation.

J.P. Aguire 11/1/95

Sensor mount. Seal

Damaged internal thread

Cannot install sensor

5 Damaged during installation or transportation

2 1 10

Sensor mount. Seal

Damaged external thread

Cannot install wire nut

4 Damaged during shipment to piracicaba

3 1 12 Damaged fitting not used by Piracicaba

Coolant containment. Hose connection. Coolant fill. M

Crack/break. Burst. Side wall flex. Bad seal. Poor hose rete

Leak 8 Over pressure 8 Burst, validation pressure cycle.

1 64 Test included in prototype and production validation testing.

J.P. Aguire 11/1/95 E. Eglin 8/1/96



Failed mount 5 Vibration 9 Vibration w/road tapes 3 135 Obtain GMB vibration road tape.

J.P. Aguire

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When should FMEAs be developed?When should FMEAs be developed?

When new systems, designs, products, or processes are designed

When existing systems, designs, products or processes change for any reason (we need a systematic method to evaluate the change)

When new applications are found for current systems, designs, products, or processes

When new metrology, test, software or process equipment is evaluated and purchased

As a general risk assessment and risk reduction tool

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Types of FMEAsTypes of FMEAs

System DesignSystem design & alternatives FMEAsMain system design FMEAsSystem software

Detailed DesignSubassembly FMEAsComponent FMEAsSubsystem software

ProcessProcess FMEA by operation or process step

EquipmentMeasurement, process equipment, computers, phone systems, test equipment etc.

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Focus of FMEA typeFocus of FMEA type

System Design FMEA

DetailedDesign FMEA Process FMEA Equipment FMEA

Main systems, Major Subsystems

Focus:Minimize failures of the system design

Goal:Maximize system quality, reliability, cost and maintainability

Subsystems, Components

Focus:Minimize design related failures of the subsystem and components

People, Machine, Method, Material, Measurement, Environment

Focus:Minimize failures of the process

Hardware, Software, Interface, Tooling, Material handling, Performance

Focus:Minimize failures of the process equipment

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Benefits of FMEABenefits of FMEA

Proactive approach (does not infer a problem) Eliminate potential causes of failuresSelect better design and or process alternativesDevelop process controls, containment and test methodsDevelop preventive maintenance programsDevelop problem response plans

Reactive approach (we have a problem… now what?)Analyze known failures due to a specific process stepUsed as a risk assessment toolPrioritize corrective action to prevent/reduce reoccurrence of failuresStrengthen control and containment of current failuresDevelop problem response plans

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Benefits of FMEABenefits of FMEA

Process improvement

Reduce total process time and down time for better productivity

Other uses

Preserve, transfer and share knowledge (inter plant/site)

As a training tool

As a feedback tool to equipment/product suppliers for further improvement

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FMEA PreparationFMEA Preparation

Section II FMEA PreparationDetermine scope and objectivesIdentify FMEA participantsOrganize and review relevant data

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Determine Scope and ObjectiveDetermine Scope and Objective

Type of the FMEA (System, Design, Process or Equipment)Stop and start points (includes, does not include)Objectives of the FMEASpecify desired results (improvement goals or risk assessment)Other considerations

Level of design Process flowLevel of detailPotential actions

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Identify FMEA ParticipantsIdentify FMEA Participants

Based on the objective and scope, determine who can effectively contribute to the development of the FMEA

Design experts

Process experts

Customers

Suppliers

Technicians

Failure analysis

QA

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Organize & Review Design or Process DataOrganize & Review Design or Process Data

Based on the objective, review relevant data

Internal data sources:

Past product or design failures

Yield by product or process operation

Defect rates by product or operation

Process flow charts

Equipment maintenance records

Downtime logs

External data sources:

Functional field failures

Customer complaints

Returned materials

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FMEA Definition Exercise FMEA Definition Exercise

FMEA Objective, scope and goal(s):

Key Date: FMEA Type: DesignSystem: Potential FMEA Number:

Subsystem: Failure Mode and Effects Analysis (FMEA) Prepared By: Component: Design FMEA Date:

Design Lead: Revision Date: Core Team: Page: of

1. Create an objective, scope and goal statement for your FMEA.

2. Identify the type of FMEA (System, Design, Process or Equipment).

3. Identify the team you need to help complete the FMEA.

4. Be prepared to share your work.

Create an FMEA definition for your project.

In Class Exercise: 10 Min

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FMEA GenerationFMEA Generation

Section III FMEA GenerationDevelop process flow diagram or WBSIdentify potential failure modeDetermine effects of failure modesIdentify potential causes of the failureDetermine current controls for the causesDetermine current containment for failuresCompute RPNs for each potential failure

21© TLC, FMEA 42703

Identify process flow or WBSIdentify process flow or WBS

Develop Work Breakdown Structure (WBS) for System or Design FMEA. WBS is a way of defining the major subsystems, design elements and components of a product. A product BOM may be useful as well.

Develop process flow diagram for process or equipment FMEA

־ Understand the specific operations in the process flow

־ Understand the specific machine functions

־ Identify what specifically the FMEA will focus on

Link failure/defect data to the process flow or WBS

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Identify critical design functions or process stepsIdentify critical design functions or process steps

DesignPrimary and secondary design functionsFeatures that influence customer satisfactionDesign robustness and redundancy for reliability and safetyProduct appearance and packaging issues

ProcessProcesses that influence customer satisfactionLook for areas that require a heavy dependency on inspectionReview all low yielding operationsLocate areas with a high WIPLook for redundant equipmentLook for cost savings opportunities

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Identify potential failure modesIdentify potential failure modes

Identify each potential failure mode

For each component, subsystem, system, operation or function

It does not mean it will happen, it just can happen

List all possible failure modes that can occur and enter them into the FMEA spreadsheet

Listing a potential failure mode does not indicate at this point a problem or that it is actionable

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Potential Failure Mode ExamplePotential Failure Mode Example



Sensor mount. Seal

Compression set

Sensor mount. Seal


Sensor mount. Seal


Sensor mount. Seal


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Identify Potential Failure Modes ExerciseIdentify Potential Failure Modes Exercise

Potential Failure Modes for your FMEA

1. List the elements of the system, design, process or machine.

2. For each element identify potential failure modes.

3. You may have multiple failure modes per design feature or process operation. Make sure a row is dedicated for each failure mode.

4. Be prepared to share your findings.


26© TLC, FMEA 42703

Determine Effects of Failure ModeDetermine Effects of Failure Mode



List potential effects for each failure mode

Start with known effects from past history, then brainstorm other possible effects

Effects may include:Local effect

within the design or subsystem, downtime or defectsDownstream effect

subsequent product function or process stepEnd effect

Test, quality/reliability

Assign severity ranking

If multiple potential effects, add a row for each

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System Severity RankingSystem Severity Ranking

System FMEA Severity Rating

Effect SEVERITY of Effect RankingHazardous without warning

Very high severity ranking when a potential failure mode affects safe system operation without warning

10

Hazardous with warning

Very high severity ranking when a potential failure mode affects safe system operation with warning

9

Very High System inoperable with destructive failure without compromising safety

8

High System inoperable with equipment damage 7

Moderate System inoperable with minor damage 6

Low System inoperable without damage 5

Very Low System operable with significant degradation of performance 4

Minor System operable with some degradation of performance 3

Very Minor System operable with minimal interference 2

None No effect 1

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General Severity RankingGeneral Severity Ranking

General SEVERITY RANKING TABLE

Rank Category External and Internal Effect10 Liability Failure will affect safety or compliance to law9 Catastrophic customer impact

Moderate to major reliability failuresReliability / End user recallsReputation Premature end-of-life (wear out)

at risk Increased early life failuresIntermittent functionalityMajor customer impact

8 Minor reliability failures7 Customer line impact / lines down

Impacts the yield of customerCustomer Wrong package / part / marking

quality Products performing marginallyinconveniences Involved customer's special handling

Damaged the customer's equipment6 Product assembly error5 Equipment cross contamination

Internal yield Damaged to down stream equipmentor special Major yield hit

4 handling Significant line yield lossrequired Minor yield hit

3 Low line yield loss2 Special internal handling, effort or annoyance1 Unnoticed Unnoticed either internally or externally

Work together

as a team to achieve consensus concerning

ranking scores

29© TLC, FMEA 42703

Severity Ranking ExampleSeverity Ranking Example



Sev


Sensor mount. Seal

Compression set Leak 8

Sensor mount. Seal



8

Sensor mount. Seal



5

Sensor mount. Seal



4

30© TLC, FMEA 42703

Potential Failure Effects and Severity RankingPotential Failure Effects and Severity Ranking

Identify potential failure effect(s) Exercise #2Potential Failure Effects for your FMEA

1. Based on your previous work and group

2. Identify potential failure effects:

Based on data or brainstorming determine the effects of the failures and write them down

3. Determine the severity ranking of each failure effect

4. Be prepared to share your finding


31© TLC, FMEA 42703

Identify Potential Failure CausesIdentify Potential Failure Causes



Sev

Potential Cause(s)/


Prob

List the possible causes of each failure and the probability of failure

The following activities may be helpful:Cause & effect diagram (fishbone)5 WhysFault tree analysis

The cause is known when we have identified the source or origin of the potential failure

Proper cause identification requires some understanding of the failure mechanism based on the process, the physics, mechanics or chemistry

The cause is verified when we can recreate or manipulate the problem source

32© TLC, FMEA 42703

Use Cause & Effect diagram to Brainstorm Potential Root Cause(s)Use Cause & Effect diagram to Brainstorm Potential Root Cause(s)

1. Draw a horizontal line with a box connected at the far right.

2. Write the problem or effect in the box.

3. Draw 6 branches off the main stem and categorize them People, Material, Method, Machine, Measurement, and Environment.

4. Cause & Effect diagrams are usually completed in a brainstorming session with team members.

5. One team member acts as a facilitator to guide the brainstorming session to solicit ideas for potential causes from the team members.

6. Use the Cause and Effect checklist to identify problem related issues

7. The facilitator will capture potential causes and put them onto a branch or sub-branch under the correct category.

QC Tool 7: Cause & Effect Diagram

Effect

Branch

CauseCause

Cause Cause

Main stem

Sub-branch

33© TLC, FMEA 42703

Cause & Effect Diagram to Identify Failure Modes Cause & Effect Diagram to Identify Failure Modes

People Machine Method

Improper cassette loading

Insufficient vacuum

XYZ alignment

too fast

Wrong cassette

CCD Camera calibration for part location

DefectiveParts

Excessive heat

7% automated placement and insertion errors

Wrong BOM

Missing cassetteWrong program

Environment Material Measurement

When brainstorming the cause and effect diagram add frequency data to get a more complete picture of the sources of the problem

34© TLC, FMEA 42703

5 Whys Example5 Whys Example

State the potential failure, then ask why did this problem occuruntil you reach root cause. Think about where is the source of the failure and where you can affect a controllable solution.

Agent X in the Lot What?/Why?Why?Why?Why?Why?

External Source of the Agent Internal Host Error in Assay

Wrong Material Used Residual Material in Bulk Fill

Fail to Clean Filter integrity tester shared with multiple products

Insufficient Capacity Efficiency of Operation Inadequate Segregation

Five is not an absolute, could be three, four, five or more whys

35© TLC, FMEA 42703

Fault Tree Analysis to find Failure ModesFault Tree Analysis to find Failure Modes

Why use it?To logically and graphically represent the various combinations of events, both faulty and normal, occurring in a system that leads to the top undesired event.

What does it do?• Encourages people to expand their thinking• Allows for confirmation of logical links & completeness at

all levels• Helps migrate the team from theory to real world• Uncovers the true level of complexity involved in a system

36© TLC, FMEA 42703

FTA SymbolsFTA Symbols

OR Logical OR… add the probabilities

Logical AND… multiply the probabilities

Major design, machine or process element

A source of the fault

AND

Event

BasicFault Event

37© TLC, FMEA 42703

FTA SymbolsFTA Symbols

Trigger event… A fault event that is expected to happen

Incomplete event. Not fully developed due to a lack of information

Conditional event. Indicates a restriction or condition to the logic

Transfer in… from another FTA flow

Transfer out… to another FTA flow

38© TLC, FMEA 42703

FTA ExampleFTA Example

No grease on

shoe lands atfacing contact

Oversizedshoes for

drum (width)

Fluid pressure not free

to release

Springsbroken

Brake does notrelease

Weaksprings

SOURCE: K. E. Case and L.L. Jones, Profit Through Quality: Quality Assurance Programs for Manufacturers, (1978)

39© TLC, FMEA 42703

FTA ExampleFTA Example

Shoes wet (e.g., water)

Brake performancemarginalBrake does not work

Fillings not cleaned afterdrums turned

Fluid low

Master cylinderdefective

(subsystem)

Improper in-stallation of

shoes, sprgs., whl. cylinder

Excessive wear

Fluid leak

Poor shoe to drum arc fitForeign material shoesor drum

Contaminated fluid

Drums not true

Springs uneven or deformed

Shoes improperlybonded

Grease from bearings on

shoes or drum

Improperly bled brakes

Wheel cylinder leaking

(subsystem)

Brake linebroken

or leaking

Master cylinderleaking

Bleed zerklooseSOURCE: K. E. Case and

L.L. Jones, Profit Through Quality: Quality Assurance Programs for Manufacturers, (1978)

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Assign Probability of Failure RankingAssign Probability of Failure Ranking

Referring to probability of failure ranking table, the matrix should be modified based on type and availability of historical data:

Field failure data, DPPM, defect frequency Pareto, SPC charts, periodical measurement etc.

Evaluate the probability of failure for each cause. One number can also be used to represent all potential causes -pick the worst case

(1, remote through 10, very high)

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Probability of FailureProbability of Failure

PROBABILITY of Failure Failure Prob RankingVery High: Failure is almost inevitable >1 in 2 10

1 in 3 9High: Repeated failures 1 in 8 8

1 in 20 7Moderate: Occasional failures 1 in 80 6

1 in 400 51 in 2,000 4

Low: Relatively few failures 1 in 15,000 31 in 150,000 2

Remote: Failure is unlikely <3.4 in 1,000,000 1

42© TLC, FMEA 42703

ExampleExample



Sev

Potential Cause(s)/


Prob


Sensor mount. Seal

Compression set Leak 8 Gasket material 7

Sensor mount. Seal




2

Sensor mount. Seal




2

43© TLC, FMEA 42703

Identify Potential Failure CausesIdentify Potential Failure Causes

Potential Failure Causes and Probability for your FMEA

1. Based on your previous work and group.

2. Identify potential failure causes:Based on data or brainstorming determine the cause of the failures and write them down

3. Determine the probability of failure ranking of each failure cause.


44© TLC, FMEA 42703

Determine Current Controls/TestsDetermine Current Controls/Tests

Describe current control in place for each potential cause

Control can be either prevent failure from occurring or detect the failure after it occurs

Assign control ranking (DET)Detection is the likelihood of the control to detect a failure or prevent failure mode

Use one detection number to represent controls per cause-pick worst case. One detection number to represent all control per failure can also be used-pick worst case (1, effective through 10, ineffective)

45© TLC, FMEA 42703

Determine Controls for CausesDetermine Controls for Causes

Types of Controls

Measurement Based Control Test & Inspection• Management Dashboards & Review Test • Statistical Process Control Inspection (poor effectiveness and costly)

Documentation Periodic Checks• Process Flow Diagrams Scheduled Maintenance

• Product Drawings, Schematics Scheduled Calibration

View controls from a perspective of six methods for controlling performance

Different problems require different types of control

• Process Management Plans Training and Operator Certification• Written Procedures Audits

Design Incentives• Design out Product Problems Measures that are associated with a bonus

• Mistake Proofing Measures that are associated with a penalty• Robust Process Design

Design Reviews

46© TLC, FMEA 42703

Inspection EffectivenessInspection Effectiveness

Inspection by definition is an incapable process. Under good conditions the inspector will detect the defects correctly only 85% of the time. 15% of the defects will escape from the process. Consider this when rating inspection’s effectiveness in defect containment.

Defect Rate Inspection Capability Escape Rate15.00% 85.00% 2.25%10.00% 85.00% 1.50%

5.00% 85.00% 0.75%1.00% 85.00% 0.15%0.10% 85.00% 0.02%

47© TLC, FMEA 42703

Detection Ranking TableDetection Ranking Table

Detection Likelihood of DETECTION by Design Control RankingCannot Detect Design control cannot detect potential cause/mechanism and

subsequent failure mode10

Very Remote Very remote chance the design control will detect potential cause/mechanism and subsequent failure mode

9

Remote Remote chance the design control will detect potential cause/mechanism and subsequent failure mode

8

Very Low Very low chance the design control will detect potential cause/mechanism and subsequent failure mode

7

Low Low chance the design control will detect potential cause/mechanism and subsequent failure mode

6

Moderate Moderate chance the design control will detect potential cause/mechanism and subsequent failure mode

5

Moderately High Moderately High chance the design control will detect potential cause/mechanism and subsequent failure mode

4

High High chance the design control will detect potential cause/mechanism and subsequent failure mode

3

Very High Very high chance the design control will detect potential cause/mechanism and subsequent failure mode

2

Almost Certain Design control will detect potential cause/mechanism and subsequent failure mode

1

48© TLC, FMEA 42703

Additional Detection CriteriaAdditional Detection Criteria

Detection Additional Detection Criteria RankCannot Detect Absolute certainty of non-detection of defective product prior to shipment 10Very Remote Test/inspection gates probably will not detect defective product 9

Remote Test/inspection gates will catch all but 25% of defective product 8Very Low Test/inspection gates will catch all but 10% of defective product 7

Low Test/inspection gates will catch all but 1.00% of defective product 6Moderate Test/inspection gates will catch all but 0.25% of defective product 5

Moderately Hight Test/inspection gates will catch all but 500 DPM of defective product 4High Test/inspection gates will catch all but 60 DPM of defective product 3

Very High Test/inspection gates will catch all but 3.4 DPM of defective product 2Almost Certain Test/inspection gates will catch all but 1 DPB of defective product 1

49© TLC, FMEA 42703

Controls and Detection ExampleControls and Detection Example



Sev

Potential Cause(s)/


Prob


Controls

Det


Sensor mount. Seal


1

Sensor mount. Seal




2 Added rib. 1

Sensor mount. Seal




2 1

50© TLC, FMEA 42703

Determine Controls for CausesDetermine Controls for Causes

Controls and Detection Ranking for your FMEA


2. Identify current controls:Evaluate current controlsIf no control is present state “None”Brainstorm potential control improvementsDetermine realistic control points or methods that should be added to the design process, process, equipment, or test sequence

3. Determine the detection (DET) ranking for the control(s)Use one detection number to represent controls per cause - pick worst case. (1, effective through 10, ineffective) if none ranking is 10


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FMEA Action PlansFMEA Action Plans

Section IV FMEA Action PlansPrioritize failure modesDetermine recommended actionsAssign owners and completion datesVerify effectiveness with new dataReview and update FMEA

52© TLC, FMEA 42703

Prioritize Actions for Potential Failure ModesPrioritize Actions for Potential Failure Modes

Rank failure modes by RPN score from high to low

Based on RPN and engineering judgment determine which of the failure modes require immediate action

53© TLC, FMEA 42703

Determine recommended actionsDetermine recommended actions

Prioritize actions based on top RPNs

Determine actions to reduce RPNsActions can be devised to:

1) reduce/eliminate occurrence2) improve control 3) improve containment by increasing the

probability of detection

Changing the design or process to eliminate the possibility of failure occurrence is always preferred; however, not always possible

54© TLC, FMEA 42703

FMEA Worksheet Computes RPNsfor each Potential FailureFMEA Worksheet Computes RPNsfor each Potential Failure

Calculate Risk Priority Number (RPN)

For each potential failure mode

RPN= Severity * Probability of Failure * Detection

High RPN numbers relative to one another require action

RPNs are used to prioritize improvement activities in the design or process

Don't use RPNs as relative indicators from one FMEA to another. They are only comparable within the FMEA.

55© TLC, FMEA 42703



Sev

Potential Cause(s)/


Prob


Controls

DET

RPN


Sensor mount. Seal


1 56

Sensor mount. Seal




2 Added rib. 1 16

Sensor mount. Seal




2 1 10

Sensor mount. Seal




3 1 12




1 64



Failed mount 5 Vibration 9 Vibration w/road tapes 3 135



Hose leak 6 Overpressure. Poor clamp

5 Burst, validation pressure cycle w/GMB clamps.

2 60

56© TLC, FMEA 42703

RPN InterpretationRPN Interpretation

RPN InterpretationRPN NumberHigh Due to prob. of failure Change design or process High Due to severity Change design or process High Due to detection Change process control/test methodModerate Due to detection Consider improving present control/test methodModerate Due to prob. of failure Consider changing design or process Moderate Due to severity Consider changing design or process Low All Maintain present status

57© TLC, FMEA 42703

Compute RPNs for Each Potential FailureCompute RPNs for Each Potential Failure



2. Compute RPNs for each potential failure mode.

3. Evaluate the RPN numbers.

4. Which ones require action?

5. What action appears to be appropriate, modification of the design or the control?



58© TLC, FMEA 42703

Assign owners and completion datesAssign owners and completion dates

Identify the owner for for problem solution (Corrective Action)

Get commitment from owner on action plans and completion dates

Match expertise and availability to the task

59© TLC, FMEA 42703

FMEA with ActionsFMEA with Actions



Sev

Potential Cause(s)/


Prob


Controls

DET

RPN



Completion Date


Sensor mount. Seal


1 56 Use imported material

Sensor mount. Seal




2 Added rib. 1 16 Implement holding rib in design. New fitting design. Prototype validation.

J.P. Aguire 11/1/95

Sensor mount. Seal




2 1 10

Sensor mount. Seal




3 1 12 Damaged fitting not used by Piracicaba




1 64 Test included in prototype and production validation testing.

J.P. Aguire 11/1/95 E. Eglin 8/1/96



Failed mount 5 Vibration 9 Vibration w/road tapes 3 135 Obtain GMB vibration road tape.

J.P. Aguire



Hose leak 6 Overpressure. Poor clamp

5 Burst, validation pressure cycle w/GMB clamps.

2 60 Obtain GMB clamps and clamping specification.

J.P. Aguire 12/1/95

60© TLC, FMEA 42703

Verify Effectiveness with Actions CompletedVerify Effectiveness with Actions Completed

Complete action plans

Gather new data after implementation of recommended action (solution)

Recalculate RPNs based on new data or design modification

61© TLC, FMEA 42703

Update New RPN based on Design or Process ActionsUpdate New RPN based on Design or Process Actions

Action Results



Completion DateActions Taken

New

Sev

New

Pro

b

New

Det

New

RPN

Use imported materialImplement holding rib in design. New fitting design. Prototype validation.

J.P. Aguire 11/1/95

62© TLC, FMEA 42703

Compute New RPNs for Each Potential FailureCompute New RPNs for Each Potential Failure



2. Based on the changes to the design, process or control assign new SEV, PROB, or DET numbers and compute the new RPN.

3. Review the revised NEW RPN numbers. Has the action resulted in reduced risk?



63© TLC, FMEA 42703

Review and update FMEAReview and update FMEA

Make changes to FMEA based on new RPNs and continue to work on the next highest ranking RPN

Endpoint of exercise is to be determined by the team

Keep all revisions of FMEA

Review and update FMEA as conditions, processes and performance change

64© TLC, FMEA 42703

SummarySummary

FMEA is a powerful tool to examine failure modes and proactively prevent their occurrence

Systematic application of FMEA to Products, Designs, Processes and New Equipment will reduce defects and their impact to customer satisfaction

Involvement of the right people early in the process and applying a structured FMEA methodology will have the greatest impact on failure reduction

FMEA should not be generated in a vacuum. Make sure you have the right data available during the FMEA generation.

65© TLC, FMEA 42703

ReferencesReferences

Bass, L. 1991. Cumulative supplement to Products liability: Design and manufacturing defects. Colorado Springs, Co.: Shepard’s, McGraw-Hill.

Blanchard, B. S. 1986. Logistics engineering and management. 3d ed. Englewood Cliffs, N.J.: Prentice Hall.

Blanchard, B. S., and E. E. Lowery. 1969. Maintainability-Principles and practices. New York: McGraw-Hill.

Brassard, M., and D. Ritter. 1994. The Memory Jogger II. First ed.

Metheun, MA: Goal/QPC.

Chrysler Corporation, Ford Motor Company, General Motors Corporation. (February 1995). Potential failure mode and effects analysis reference manual. Second edition.

Eachus, J. 1982. Failure analysis in brief. In Reliability and quality handbook, by Motorola. Phoenix: Motorola Semiconductor Products Sector.

Stamatis, D.H 1995. Failure Mode and Effect Analysis: FMEA from Theory to Execution. Milwaukee, WI: ASQC Press.

© Course materials are copyrighted by Thomas A. Little Consulting. Any duplication or use of these materials or sections of these materials requires the express permission of TLC prior to use. 2003

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