Failure Mode and Effective Analysis

7/28/2019 Failure Mode and Effective Analysis

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FMEAFailure Mode And

Effective Analysis

All Rights Reserved

Trade marks and/or proprietry names indicated are the property of respective owners.

Process Failure Mode And Effects AnalysisDana Quality Assurance Services+91-80-6549970 Failure Mode Effective Analysis 1


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Low - High

Process

1 to 10

Primary Process Responsibility Outside Suppliers Affected Engineer

Model year /Vehicle(s) Part Number

Other Div or people involved Scheduled Production Released PMEA Date Rev

Approvals Quality Assurance Manager Quality Assurance Engineer

Operations Manager Senior Adivisor

Part Name Process Function Potential Failure Potential Effects of Potentail Cause OF Failure Current Control Recommended Actions

Operation Mode Failure Actions and Taken

Number Status

SIR Take TPPE Wrong Material Fragmented Container Insufficient Supplier Material Certif

Container Material Held in Unpredictable Control improper required with

1 Storage Area Deployement Handling each

Misidentified shipment

Material release

Verification

Out of Spec Fragmented Container Open Boxes Visual

Material Unpredictable Inspection

Deployement

Contaminated Fragmented Container Open Boxes

Material Unpredictable

Deployement

Material Fragmented Container Engineering Change Release

Occurred

Severity

Detection

RPN

Occurred

Severity

Detection

RPN

1 9 2 18

3 10 3 90

1 9 7 63

1 10 7 70

Dana Quality Assurance ServicesF il M d Eff i A l i


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Composition Unpredicatble Suppier Change verification

Change Deployement Green OK Tag

Release

Verification

2 Move To Unreleased Fragmentation Untrained LTO Check For OK

Approved Untrained Personnel Tag at press

Storage Trace Card

Check List

Training

5 10 1 50

Dana Quality Assurance Services

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To understand the role and function of the FMEA

To understand the concepts and techniques of

Design FMEA and how to apply it.

To Understand the concepts and techniques of

Process FMEA and how to Apply it

To understand the role and function of FTA

To understand the concepts of Zero Quality

Control or Mistake - Proofing (e.g. Poke - Yoke) and

its implications for FMEA.

Course Goals

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Customer Requirements

Engineering Specifications

System And Components Specifications

Process and Supplier Requirements and

ControlDevelop System Design And Process FMEA

Eliminate Potential Failures

Improve Upon Design And Process

Design is the Critical element

How FMEA Fits With Elements Of TQM

What is An FMEADana Quality Assurance Services+91-80-6549970 Failure Mode Effective Analysis 5


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An Advanced Quality Planning tool used to

evaluate potential failure modes and their causes.Prioritizes Potential Failures according to their Risk

and drives actions to eliminate or reduce their

likehood of occurrence.

Provides a disciplinary /methodology for documenting

this analysis for future use and continuous process

improvement.

By its self ,and FMEA is not a problem solver .It is

used in Combination with other problem solving tools,

The FMEA presents the oppurtunity but does notSolve the Problem .

FMEAs Have Failure Modes



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The team developing the FMEA turns out to be one

individual.The FMEA is created to satisfy a customer or third

party requirement ,not to improve the process.

The FMEA is developed too late in the process and

does not improve the product /process development

cycle.The FMEA is not reviewed and revised during the life

of the product .It is not treated as a dynamic tool.

The FMEA is percieved either as too complicated or

as taking too much time.

FMECA

Failure Mode Effects And Critically Analysis

Origins



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1950's Origin - Aerospace & US Military

To categorize and rank for focusTargeted prevention as a critical issue

Addressed saftey issues

FMEA

Failure Mode And Effects Analysis - 1960's and 70's

First notices & used by reliability engineers

System of various group actvities provided through documentation

of potential failure modes of products and /or processes and its

effect on product performance .

The evaluation and documentation of potentail failure modes of a product & process

Actions are then identified which could eliminate or reduce the potential failure.



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Automotive

QS 9000 Paragraph 4.2

Cited in the AIAG APQP Manual

Process Saftey Management Act (PSM)

Where And Why



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CFR 1910.119999999 lists the process FMEA as one of about

6 methods to evaluate hazards

Example ICI Explosives - Hazardous Operability studiesFDA - GMPS

One of several methods that should be used to verify a new design (21 CFR

Part 820).Inspectors check list questions cover use of the Design FMEA.

ISO 9001

Requires Preventive Actions .The utilization Of FMEAs is one

Continuous iimprovement tool which can satisfy the requirement .

ISO 14000

Can be used to evaluate potential hazards and their accompanying risks.

Components

sub systems,

ain system

Subsystems

Main systems

Man power

Machine

Components

System Design Process

Material

Measurement

Types Of Automotive FMEAs

Method



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Focus Focus Focus

Minimize failure Minimize processMinimize Failure effects on the failures effects on

Effects on the system design the Total Process.

Objective /Goal Objective /Goal Objective /Goal

Maximize System Maximize Design Maximize Total

Quality,reliability Quality ,reliability Process Quality

Cost Cost and reliability,cost,

and maintainability. maintainability. Process,Gauges Productivity andmaintainability .

Syste

FME

Design

FME

The effect from the

The Ramifications of

the problem

The Problem The cause (s) of the

Problem

System FMEA with a

The cause (s) of the

problem from the

Effect CauseFailure Mode

New Root Causes for

the Design Failure

Machines

Tools ,Work

Stations

Production lines

Operator Training

Relationships Of Automotive FMEAs

Envirnoment



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Proces

FME

Design FMEA Process FMEA

Sign Off

Concept Design

Go - Ahead

Design

Completion

Modes

Production

Start

Automotive FMEA Time Line

Problem from the

Design FMEA

Prototype

Build

Eng/Mfg

system FMEA

The same effect as the

Design FMEA

The causes of the Specific Root Causes

For the Process Failure

ModesBetter Definition



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Design FMEA :

Start early in process.Complete by the time preliminary

drawings are done but before any tooling is initiated.

Process FMEA :

Start as soon as basic manufacturing methods have been

discussed .Complete prior to finalizing production plans

and releasing for production.

Customer Input

Team - Team Selection ( Cross - Functional)

Ranking - Ranking Of Decisions

Some Key FMEA Terms



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Risk Priority Assessment

Design Process

Production Process

AIAG Automotive Industry Action Group

APQP Advanced Product Quality Planning

DFMEA Design Failure Mode And effects analysis

DOE Design Of experiments

FMA Faiulure Modes Analysis

FMEA Failure Mode and Effects Analysis

KCC Key Control Characterstic

Automotive Acronyms



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KPC Key Product Characterstic

PFMEA Process Failure Mode and Effects Analysis

PPAP Production Part Approval Process

PSW Production Submission Warrant

QFD Quality Function Deployement

Characterstic : A distinguishing feature ,dimension or property of a process or its output ( Product) on

Which variable or attribute data can be collected .

Characterstic ,Critical ,Chrysler Definition: Characterstic applicable to a component ,

material assembly or vehicle assembly operation which are designated by Chrysler Corporation

Engineering as being critical to part function and having particular quality ,reliability and /or durability

significance .These include characterstic identified by the shield ,pentagon ,and diamond.

Characterstic , critical ( Inverted Delta) , Ford Definition: Those Product requirements

( Dimensions , performance tetst) or Process parameters that can affect compliance with government

regulations or safe vehicle/product function ,and which require specific supplier ,assembly ,shipping or

monitoring and included on Control Plans.

Characterstic ,Key Control ( KCCs): Those process parameters for which variations must be

Controlled around a target value to ensure that significant characterstic is maintained at its target value.

KCCs require ongoing monitoring per an approved Control Plan and Should be considered as candidates

Characterstics I



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For Process improvement .

Characterstic, Key Product ( KPC): those product feature that affect subsequent operations,

Product function ,or customer satisfaction .KPCs are established by the customer engineer ,Quality

representative ,and supplier personnel from a review of the Design and Process FMEAs and must beincluded in the Control Plan.Any KPC s included in Customer -released engineering requirements are

provided as a starting point and do not affect the suppliers responsibility to review all aspects of the design,

Manufacturing process,and customer application and to determine additional KPCs.

Characterstic , process : Core team Identified process variables ( Input variables) that have a

Cause and effect relationship with the identified Product Characterstic (s) which can only be measured at

the time of occurrence.

Characterstic , Product : Feature or properties of a part , Component or assembly that are

described on drawings or other primary engineering information

Characterstic , Product , Critical (D) Chrysler Definition : a defect which is critical to part Function and having particular qu

Characterstic , Product , Major , Chrysler Definition : a defect not critical to function ,but which could materially reduce the

Satisfaction , or reduce production Efficiency .

Characterstic , Product ,Saftey /Emmission /Noise (S), Chrysler Definition: A defect

Which will affect compliance with Chrysler Corporation and Government Vehicle Saftey /Emission /Noise

Characterstic II



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Requirements.

Characterstic ,Saftey ,Chrysler Definition : Specifications of a Component.

material ,assembly or vehicle assembly operation which require special manufacturing control to assureCompliance with Chrysler Corporation and Government vehicle safety requirements.

Characterstic saftey Chrysler Defnition : Specifications which require special

manufactruing control to assure compliance with Chrysler or Government vehicle saftey reqiirements.

Charactertsic ,Significant ,Chrysler Defnition : Special characterstics selected by the

supplier through knowledge of the product and process.

Characterstic , Special : Product and process charactertsic designated by the customer, including

governmental regulatory and saftey ,and /or selected by the supplier through knowledge of the product and process.

Charactertsic , Special ,Chrysler Definition : Specifications of a component ,material ,assembly or vehicle

assembly or vehicle assembly operation which are designated by Chrysler as being critical to functionand having particular quality ,reliability and durability significance .

Charactertsic Special Chrysler Definition : Specific Critical Characetrstic that are process

driven (controlled ) and therefore require SPC to measure process stability , Capability ,and

control for the life of the part.

Charactertsic ,Special Chrysler Definition : Limited to highlighting critical Characterstics on

Production ( Production) part drawings ,tools and fixture ,and tooling aid procedures where ongoing

process control is not automatically manadated.

Charactertsic , Special , Chrysler Definition: Engineering Designated specifications

Characterstics III



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or product requirements applicable to component material,assembly operations which require

special manufacturing control to assure complinace with governmental vehicle saftey,emissions

noise ,or theft prevention reuqirmenets .

Characterstic , Special , Ford Definition "Critical Charactertsic" : those productrequirements (Dimensions , Specifications ,Tests) or process parameters which can affect

compliance with government regulations or safe vehicle /Product Function and which require specific

producer ,assembly ,shipping or monitoring actions and inclusions on the control plan.

Characterstic ,Specification , Ford Definition "Significant charactertsic : those

Product ,process and test requirements that are important to Customer satisfaction and for which quality

planning actions shall be included in the Control Plan.

Charatcetrtic ,Special Ford Definition : Significant /Characterstic :

characterstic that are important to the customer and that must be included on the Control Plan.

Charactertsic ,Special , GM Definition "fit /Function : Product charactertic for which

reasonably anticipated variation is likely to significantly affect customer satisfaction with a product (other

than S/C) such as its fits , function,mounting or appearance ,or the ability to process or build the product.

Characterstic , Special ,GM Definition Saftey/Compliance : Product charcterstic for

which reasonably anticipated variation could significantly affect customer the products safety or its

compliance with government regulations (such as : Flammability ,occupant protection ,streering control,

braking etc..) Emmisions ,noise , radio frequency interference etc.

Characaterstic , special GM Definition " Saftey /Compliance : Product Charactertsic for

Characterstics IV



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Which reasonably anticipated variation could significantly affect customer the products saftey or its

complaince with government regulations ( such as : Flammibility ,occupant protection ,steering control,

braking etc) Emmissions ,noise ,radio frequency interference etc .

Characterstic , Special ,GM Definition " Standard : Product characterstic for which

reasonably anticipated variation is unikely to significantly affect a products saftey,compliance with

governmental regulations ,fit/function .

Charcterstic ,Special , Process (e.g.Critical ,Key Major , significant): A Process

characterstic for which variation must be controlled to some target value to ensure that variation in a

special product characterstic is maintained to its target value during manufacturing and assembly.

Characterstic ,Special ,Product : Core team compilation of important product characterstics

From all sources.All special characterstics must be listed on the control Plan.

Charactertic , Special Product (e.g Critical ,Key ,Major Significant ): a Product

characterstic for which reasonably anticipated variation could significantly affect a products saftey or

Compliance with governmental standards or regulations ,or is likely to significantly affect customer

satisfaction with a product.

Characterstic ,Special ,Tooling , Chrysler definition : Critical tooling

symbol used identitity special charactertic of fixtures ,gauges ,developmental parts,and initial product

parts.

Control Item Part , Ford Definition:Product drawings /specifications containing Critical

Charactertics .Ford Design and Quality Engineering approval is required for changes to Control item

FMEAs and Control Plans.

Characterstic V



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Flow CHART , Preliminary Process

Description of anticipated manufacturing process

developed from preliminary bill of material and

product /process assumptions .

Flow DIAGRAM, PROCESS

Depicts the flow of materials through the process,

including any rework or repair operations .

Process Flow Document



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FMEA: Failure Mode and effects Analysis- systemized technique which identifies

and ranks the potential failure modes of a design or manufacturing of a design or manufacturing process in order to prioritiz

improvement actions.

Failure Cause Potential : How the Failure could occur,described in terms of somtheing that can be

corrected or can be controlled .

Failure Modes Analysis (FMA) : a Formal structered procedure used to analayse failure mode data

from both current and prior processes to prevent occurrence of those failure modes in the future.

Failure Mode Potential : The manner in which the process could potentially fail to meet the process

requirements and/or design intent a description of the non -conformance at that specific operation.

FMEA , Design : analytical technique used by a design responsible engineer /team as a means to assure,

to the extent possible ,that potential failure modes and their associated causes /mechanisms have been

considered and addressed.

FMEA , Machine /Equipment : Same as process FMEA , Except machine /equipment being designed is

considered the product.

FMEA , Process:Analytical technique used by a manufacturing responsible engineer /team as a means

to assure that , to the extent possible ,potential modes and their associated causes /mechanisms

have been considered and addressed.

FMEA & Failure Terms



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Control Plan: Written descriptions of the system for controlling production parts and

processes.They are written to address the important characterstics engineering

requirements of he product.Types of control Plans include "family" device or technology

Control Plans which apply to a number of parts produced using a common process.

Customer approval of control plans may be required prior to PSW submission.Refer to

Section III For customer -specific requirement .

Control Plan , Prelaunch : A description of the dimensional measurements and

material and performace tests that will occur after prototype and before full (normal)

production.

Control Plan Production: A Comprehensive documentation of product/process

characterstic ,process controls ,tests , and measurements systems occuring during mass

(normal) Production.

Control Plan , Prototype: A Description of the dimensional measurements and

material and performance tests that will occur during Prototype Build.

Control Plan Definitions


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Before Or after ?

Individual or Team Approach ?

FMEA Timing




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Process Flow Diagram(Includes All Proceses)

Process FMEA Critical Charactertsics

(On all Processes) & Failure Effects Issues

Process Control Plan( Critical Processes From FMEA)

Critical Charactertsics

& Charactertsic Control Issues

Design FMEA( On Intended Use)

Typical Automotive Triology Development

APQP Time Line




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Check For CustomerRequirements.

Give careful consideration

to that you consider a

Major Process.

Use the appropraite RPN

numbers and

considerations of other

appropraite information/

data to determine Critical

Give careful Charactertics.

consideration todefining Contro Develop Control

plan stages mechanisms appropriate

Prototype for critical

Pre-launch charactertsic

Production

Element for every

Process

Develop the

Control Plan with

Critical

Charactertsics

flow Listing

Enter Every

Major Process

from flow listing

into FMEA Form

Develop FMEA(s)

Automotive Document Development

Develop Process




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Advanced Product Quality Planning Timeline

Process Flow Listing Flow /Process Control Plan(Includes All Processes) (All Major Processes)

APQP Procedure should Process Flow Listing

Trigger this Process Becommes the

Process Control Plan

Some Elements may Process FMEAbe Included On ( All MAJOR Processes)

Use to Determine

Critical Charactertic

From RPN

Design FMEA( Intended Use)

Control Plan / Process Flow Combination Example




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Check for customer

requirements.

Give careful consideration

to what you consider a

Major process.

Use the appropriate RPN

numbers and

considerations of other

appropriate information/

data to determine critical

charactertics.

Develop Control

mechanisms appropriate

for critical

charactertsics.

One Document ? Or More ?

Process in the

Control Plan

Revise the

Control Plan with

Critical

Charactertsics

Major Process

Form Flow Listing

into Control Plan

Form

Develop FMEAs

Element for Every

Control Plan /Process Flow Combination ExampleDocument Development

Develop Process

Flow Listing

Entry Every




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Manufacturing Entity

Receiving Machine or Machine Pack

Cell 1 Or Cell 2

& Ship

Segmenetd + By machine or Cell Receiving

Pack

Device ,Technology or Family = a Flow of a technology or device & Ship

QS 9000 :1996 - FMEAs

Internal Or

External

Customer

Machine

or Cell 3




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4.2.3 - Quality Planning

Process Failure Mode And effects

analysis ( Process FMEAs)

Process FMEAs shall consider all special

Charactertsics.Efforts shall be taken to improve

the process to achieve defect prevention ratherthan defect detection.Certain customers have

FMEA review and approval requirements that shall

be met prior to production part approval ( See

Customer specific pages).Refer to the Potential

Failure Mode and effects Analyisis reference

manual.


QS 9000 :1996 - Control Plans




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The Control Plan

Suppliers shall develop ControlPlans at the system

subsystem,Component and /or material level,as apporiatefor the product supplied.

The Control Plan requirement encompasses processes

producing bulk material(e.g Steel , Plastic resin ,Paint ) as

well as those producing parts.

The output of the advanced quality planning process,beyond

the development of robust processes,is a control Plan.

control Plans may be ebased on existing plans ( for mature

Products and capable processes). New Plans are required

when products or processes differ significantly from those in

current production.


QS 9000 : 1996 - Control plans




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The Control Plan

The Control Paln shall cover three distinct phases as appropriate:

Prototype - a description of the dimensional meausrements and

material and performance test that will occur during Prototype build.

Note: Prototype Control Plans may not be required from all suppliers

Prelaunch - a description of the dimensional meausrements and

material and performance test that will occur after Protype and

before full Production.

Production - a Comprehensive documentation of product /process

characterstcis , process controls test and measurement systems that

will occur during mass production.

Suppliers shall establish cross - functional teams to develop Control Plans for

approval by the appropriate customer engineering and quality personnel

unless this approval requirement is waived by the customer .In Some cases,

the Customer will establish a cross functional team to develop the control Plan.

Quality Planning - 4.2.3 S

SemiConductor Supplement




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During the advanced quality planning processes,the supplier shall

include all processes from the incomming material through shipping

and warehousing.

Failure Mode And Effects Analaysis and Control Plan Documents

Shall include these processes.

The Intent :

The supplier Shall " Consider " All Processes .But does it mean that

all process shall be included In the FMEA and Control Plan?

6.2 Overview

APQP Manual : 1995




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A Control Plan is written description of the

system for controlling parts and processes "

"In effects, the Control Plan describes the actions

that are required at each phase of the process

including receiving , in - process , out going , and

periodic requirements to assure that all process

outputs will be in taste of control"

" Process Potential FMEA"

IS " aSummary of engineer's /teams thoughts

FMEA Manual : 1995




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( Including an analysis of items that could go wrong

based upon experience and past concerns ) as a

Process is developed".

" A process FMEA should begin with a flow chart/

risk assessment of the general process.This flow

chart should identify the products charactertsics

associated with each operation."

Prevention Planning

Identifies Change requirements

Benifits Of FMEAs




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Cost reduction

Increased through-put

Decreased Waste

Decreased warranty costs

Reduce non-value added operations

Select proper team and organize members effectively

Select teams for each product /Service , process/system.

Create a ranking system

FMEA Pre Requisites




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Agree on format for FMEA matrix ( Typically set by AIAG)

Define the customer and customer needs/

expectations

Design /Process requirements

Develop a process flow Chart

What is a team

Two or more individuals who coordinate actvities

to accomplish a common task or goal.

The Team




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Maintaining Focus

A sepearte team for each product or projects.

Brainstorm

Brainstorming ( The Team ) is necessary as the

intent is to discover many possible possibilities.

Two Types Structures

Natural Work Group Task Team

Work area or unit Representatives who have key

representatives from support information or are stakeholders.

groups on as - needed basis.

Participation is mandatory. Assigned by steering committee

Team Structures

Membership

Member SelectionDana Quality Assurance Services



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or upper management

Assigned by management or Assigned by or negoiated with

identified by team and within its steering committee or upper

authority. management.Ongoing Disbands when task is finished .

Leader appointed by management. Leadership shared or delegated by

members.

Are management directed and foccussed

Build their own identity

Are accountable and use

Measurements

roject Identificatio

Team Life Span

Leadership

Succesful Teams




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Have corporate champions

Fir into the organization

Some Teams Just " Do not

Are cross - functional Work"

Determine if there should be a meeting

Decide who should attend

Provide advance notices

Maintain meeting minutes or records

Basic Team Rules




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Establish ground rules

Provide and follow an agenda

Evaluate meetings

allow NO interruptions

Ground Rules are an aid to "self -

management"

Team must develop their own ground rules

Once deveolped,everyone must live by them

They can modify or enhance the rules as they

Team Ground Rules




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continue to meet

Clarify

Participate

Listen

Summarize

Stay on Track

Team Meeting Responsibility




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Manage time

Test For Consensus

Evaluate meeting process

One Person makes the decision

One person consults the group,then

makes the final decision

Team or group makes decision based

upon majority rule or consensus

Decision Criteria /Model




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Start During Prototype stage

Design Engineer - Generally the Team Leader

Test Engineer

Reliability Engineer How do you Currently

Material Engineer prevent problmes from

Field Service Engineer occuring?

Component Process Engineer

Vehicle Process Engineer

Styling Engineer

Project Manager or Rep.

Design FMEA Team




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Quality Engineer

Customer Contact Person

Others ,including Mfg., Sales , Mkting ,QA / QC, Process ,Pacakaging

Process Engineer - Generally the Team MembersProcess Operator

Industrial Engineer

Design Engineer How do you presently

Reliability Engineer prevent problems?

Tooling EngineerMaintenance Engineer

Styling Engineer

Project Manager or Rep.

Quality Engineer

Process FMEA Team Members




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Others including supplier , Sales ,QA/QC, MFG.

Design FMEA Customer

End User : person who uses the product

Use Failure

This can help in Repair manuals & Filed Service

More in the DFMEA section herein.

Process FMEA Customer

Subsequent operations

Defining the Customer




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End users : person who uses the product

More in the DFMEA section herein

Do not mix up :

Design Failures & Causes

With

Process Failures & Causes

Design Failures Process Failures

Insufficient lubrication capabilitry Insufficient lubrication applied

Incorrect specified Incorrect material used

CAUTION




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RPN = (S) x (O) x(D)

S = Severity

O = Likehood of Occurrence

D = Likelihood Of Detection

Prevention vs Detection- Automotive Expectations:

1000 is the Maximum and 75 is considered "OK"

High and low numbers are the important ones to consider

Input Concept

Risk Assessment (RPN) Factors




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From Experience From

& Data Guess

Design FMEAItem- Function Potential Failure Potential Effects Potential Current Design Recommended Responsible

Mode Of Failure Cuases /Mechanisms Of controls Actions Activity and

Failure and status target completion

date

Process FMEAProcess Function Potential Failure Potential Effects Potential Current Design Recommended Responsible

Requirements Mode Of Failure Cuases /Mechanisms Of controls Actions Activity and

Failure and status target completion

date

Device /

Process

Failure Mode Chance OF Severity Chance Not

Occurrence Detected

RPN Flow

Effect ControlCause

Severity

Occurenc

Detection

RPN

Occured

Severity

Severity

Occurenc

Detection

RPN

Occured

Severity




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Design FMEADana Quality Assurance Services

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A Design FMEA is an analytical

Techniques utilized primarily by a Design

FMEA team to ensure potential Failure

modes and their associated causes are

identified , Considered and addressed.

Reference page 8 in the AIAG FMEA Reference Manual

This systematic approach parrels,Formalizes and documents the

mental discipline that an Engineer normally goes through in any

Design process.

Design FMEA FociDana Quality Assurance Services



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Customers include

End userRepair functions

Dealership or other Sales Outlet

Designer of the next level system or product

Process Engineers

Assembly Engineers

Test Engineers

Product Analysis

Start with a list of :

Typical Design Considerationms




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What the design is expected to do

What the design is expected NOT to do

Design Intent

Customer Needs

Customer Wants

Product Requirement

Manufactring assembly requirements

Think about what Quality Function Deployement

documents in your customer Contacts

company Competative Analysis

define these Known Product Quality

Reliability Requirements

Manufactruring Requirements

Aids in the objective evaluation of design requirements and

Design FMEA Benefits




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alternatives.

Increases the probablity that potentail modes and their

effects on the system/product have been considered.

Aids in the planning of design test and development programs

Aids in analyzing field concerns ,design changes and in

developing advanced designs.

Ranks potential failure modes according to their effect on the

customer ,thus prioritizing improvements and development

testing.

Provides an open issue format for recommending and tracking

risk reducing actions.

Can reduce product development timming ,Production startup

problems ,reduce costs and enhance product quality,reliabiity

and saftey.

The Design FMEA is a living document and should be initiated

More Design FMEA Considerations


+91-80-6549970Failure Mode Effective Analysis 53


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at ,or by ,design concept completion.

The design FMEA should be continually updated as changes

occur throughout all phases of product development.The Design FMEA should be fundamentally complete along with

the final product drawings.

The design FMEA addressess the design intent and assures

the design will be manufacturers /asembled to this intent.

The Potentail Failure Mode /Causes which can Covered by the Process

FMEA ad therefore should NOT be included in a design

FMEA.

Causes of design failure modes are

Design Failure Causes




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those things that ,from a designer 's

prespective ,would , by ommission or

improper use ,result in the failure mode.

Improper Tolerancing

Design Failure Cause Examples



Incorrect Stress Calculations


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Incorrect Stress Calculations

Wrong Assumptions

Wrong Material Call outLower Grade Component

Lack of design Standards

Improper Heat Treatment

Improper Torque Call out.

Design Block diagram ExampleIf the product is complex ,break it

down into smaller sub -systems .Identify

System Primary vs Secondary Fuctions.Body




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Subsystem

Exterior Window Interior

Glass Sealing Latch/

Component with Lock

Strip

Doors

Door

Inner

Panel




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Effect Critreria: Severity of Effect Ranking

Hazardous Very high ranking when a potentail failure mode affects safe 10

without vehicle operation and/or involves noncomplaince with government

warning regulation without warning

Hazardous Very high seviriaty ranking when a potential mode affects safe 9

with vehicle operation and/or involves non compliance with government

warning regulation with warning.

Very High Vehicle /item inoperable ,with loss of primary function 8

Generic Design FMEA Severity



High Vehicle /Item operable ,but at a reduced level of performance 7


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Customer dissatisfied.

Moderate Vehicle /Item operable ,but comfort convinence items inoperable 6

Customer experiences discomfort.

Low Vehicle /Item operable but comfort /convenience items (s) operable at 5reduced level of performance .Customer experiences some

dissatisfaction.

Very Low Fit & Finish /Squeak & Rattle item does not conform .Defect noticed 4

by most customers.

Minor Fit & Finish /Squeak &rattle item does not conform .Defect noticed 3

by average customers.

Very Fit & Finsih /Squeak & rattle item does not conform .Defect noticed 2

Minor by discriminating customers.None No effect 1

Possible Failure Rates Ranking

Very High : Failure is almost inevitable > 1 in 2 10

1 in 3 9

High : Repeated Failures 1 in 8 8

1 in 20 7

Moderate : Occasional Failures 1 in 80 6

1 in 400 5

1 in 2000 4

Generic DFMEA Occurrence

Probability Of Failure



Low : Relatively Few Failures 1 in 15000 3


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1 in 150000 2

Remote : Fialure Unlikely < 1 in 1,500,000 1

Detection Criteria : Likelyhood of detection by Design Control Ranking

Absoulete Design Control will not and /or can not detect potential 10

Uncertainity cause /mechanism and subsequest failure mode: or there is no

Design Control.

Very Very remote chance the design Control will detect a potential 9

Remote causes/mechanism and subsequent failure mode.

Remote Remote chance the design Control will detect a potential 8

cause /mechanism and subsequent failure mode.

Very Low Very low chance the design Control will detect a potential 7


Generic DFEMA Detection



Low Low chance the design control will detect a potential 6


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g p


Moderate Moderate chance the design Control will detect a potential 5


Moderately Moderatly high chance the design Control will detect a potential 4

High cause /mechanism and subsequent failure mode.

High High chance the design Control will detect a potentail 3


Very High Very high chance the design Control will detect a potential 2

cause /mechanism and subsequent failure mode

Almost Design Control will almost certainly defect a potential 1

Certain cause /mechanism and subsequent failure mode.

Design Controls are those actions taken as

a normal part of the development process

that are designed into the process to

minimize the occurrence of failure or to

detect specific failure modes.

Design Controls



Design controls should directly relate to the


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Design controls should directly relate to the

Prevention and/or detection of specific

causes of failures.

Reliability Tests/Prototype Testing

Design Reviews

Worst Case stress Analysis

Robust Design

Envirnomental Stress Testing

Designed Experiments

Design Control Examples

Consider

Interpretation of

DataDana Quality Assurance Services


Finite Element Analysi


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Finite Element Analysi

Variation Simulation

FT AnalysisComponent Derating ( 60% to 80 %)

100,000 Mile Pilot Test

When the failure modes have been ranked by their RPN,

corrective actions should be first directed at the highest ranked

concerns and critical items identified .

The intent of any recommended action is to reduce one or more

(or all) of the occurrence ,severity and/or detectioin rankings.Only a design revision can bring about a reduction in the

severity ranking .If no actions are recommneded for a specific

cause ,this should be indicated.

A reduction in the occurrence ranking can only be effected by

Recommended Actions



removing or controlling one or more of the causes of the failure


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g g

mode through a design revision.

An increase in design verification actions will result in a

reduction in the detection ranking ONLY.

Design FMEA doesnt rely on process controls to overcome

potentail weakness in the design: however ,it does take

technical and physical limitations of a process into consideration (Design rules)

Sample Sizes

Evaluation

For the Control Plan Frequency

Method of

characterstics

and is therefore the

Starting Point

The Process FMEA

Identifies

Critical and Significant



Evaluation


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Evaluation

Out-of-Control

Action Plan

(OCAP)

You want to understand your current process

You are looking for oppurtunities to improve

You want to illustrate a potential solutionYou have improved a process and want to

document the new process

Use a Process Flow ChartBecause:




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Lets Try A Process Flow Chart

1 Identify the process or task you want to analyze.Defining the

scope of the process is improtant because it will keep the

improvement effort from becoming manageable.

2 Ask the people most familiar with the process to help construct

the chart.

3 Agree on the starting point and ending point.Defining the scope

of the proces to be charted is very important ,otherwise the

Creating a Process Flow Chart



task can become unwieldly.


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4 Agree on the level of detaiul you will use .Its betetr to start out

with less detail ,increasing the detail only as needed to

accomplish your purpose.

5 Look for areas for improvement

Is the process standardized ,or are the people doing the work in different ways?

Are steps repeated or out of sequence ?

Are there steps that do not ad value to the output?

Are there steps where errors occur frequently?

Are there rework loops?

6 Identify the sequence and the steps taken to carry out the

Process.

7 Construct the proces flow chart either from left to right or from

Creating A Process Flow Chart



top to bottom ,using the standard symbols and connecting the


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steps with arrows.

8 Analyze the results.

Where are the rework loops?

Are there process steps that dont add value to the output?

Where are the differences between the current and the desired situation?




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TTOOOOOOOOOO makeeeeeeeee



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Use to help determine who should be involved by

identify all the work areas in a process

Use as a job aid to remind people about processs

standards

Use as a check list to collect data on where problems

occur

Use to investigate why rework is occurring at a

certain place in the process

Use the ideal process flow chart data to

communicate your proposed solution

How To Use The Flow Chart




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If a process step or box has two output

arrows ,consider whether a decision box is

needed

Remember that the people closest to the work it best .Make sure pe

involved in developing the flow chart

Software packages make flow chartproduction easy.

Flow Chart Tips




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Identifies potential product-related failure modes

Assesses the potential customer effects of the

failures

Identifies the potential internal and externalmanufacturing or assembly process causes and

identifies process variables on which to focus

controls for occurence reduction and/or detection of

the failure conditions

Develops ranked list of potential failure modes,thru

establishing a priority system for corrective action

considerations

Documents the results of the manufacturing or

The Process Potentail FMEA



assembly process


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A process potential FMEA is an analytical tool utilized by a process

FMEA team as a means to ensure potential failure modes and their

associated causes are identified ,considered and addressed.

Teams should be run by the owner of the process or someone who

understands the process well.Defines reasons for rejection at specific operations.

In preparation for the FMEA ,the assumption should be made that

the incomming parts and materials are correct.

A comparision of similar components is a recomended starting point.A

knowledge of the purpose of the design necessary.It can be cause -associated with a potential failure mode in a

subsequent operation or an effect associated with a potential failure

in a previous operation.

Each potential mode for the particular operation should be

Process Potential FMEA



listed in terms of a part or process characterstic.


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Process FMEA Foci


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Customer include:End user

Next Manufacturing or Process step

Process Engineers

Assembly Engineers

Repair FunctionsTest Engineers

Product Analysis

Dealership or other Sales Outlet



Process FMEA Beneifts


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As a systematic approach ,the process potentail FMEA

parrallels and formalizes the mental discipline that an engineer

goes through in any manufacturing planning process.

The Process Potential FMEA identifies potential product related

process failure modes.

The process potential FMEA assesses the potential customer

effects of the failures.The process potential FMEA identifies potential manufacturing

and/or assembly process causes.

The process potential FMEA identifies significant process

variables to focus controls for occurrence reduction and

detection of failure conditions.

The process potential FMEA develops a list of potential failuremodes ranked according to their affect on the customer,thus

establishing a priority system for corrective and preventive

action considerations.



More Process FMEA Considerations


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The process FMEA is a living document.

The Process FMEA should be continually updated as changes

occur throughout all phases of product development and on into

and through to the end of production.

The process FMEA should begin with a flow chart of the

processes - from receiving through shipping and warehousing.

The potential Failure Modes /Cause which can occur during

manufacturing or assembly process are covered by the Process

FMEA but some information (severity rankings,identification of

some effects ) may come from the Design FMEA.

A reduction in occurrence ranking can on by be achieved by

implementing a proces change that controls and eliminates

one or more causes of the failure mode.Dana Quality Assurance Services



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RPN



Effect Criteria Sevrity Of effect Rankingazar ou ay en angere mac ne or assem y operator . ery g sever ty

Generic PFMEA Severity


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t out ran ng w en a potenta a ure mo e a ects sa e ve c e operat onarn ng an or nvo ves noncomp ance w t government regua t on. a ure

w occur w ou warn ng.azar ous ay en angere mac ne or assem y operator . ery g sever ty

w t ran ng w en a potent a a ure mo e a ects sa e ve c e operat onwarn ng an or nvo ves noncomp nace w t government regu at on. a ure

w occur w warn ng.

ery g a or srupt on to pro uct on ne . o pro uct may ave toe scrappe . e c e tem n opera e , oss o pr mary unct onus omer very ssa s e .

g nor srupt on to pro uct on ne . ro uct may ave to e sortean a port on ( ess t an ) c rappe . e c e t em opera e , uta a re uce eve o per ormance . us omer ssa s e .

o erate nor srupt on to pro uct on ne . port on ( ess t an ) o

t e pro uct may ave to e scrappe (no sort ng) . e c e temopera e , ut some mcom ort conv en ence tem (s) nopera e

us omers exper ences scom or .

ow nor srupt on to pro uct on ne . o pro uct may ave toe rewor e . e c e tem opera e , ut some com ort conv en encetems opera e at re uce eve o per romance . utsomer

exper ences some ssa s ac on.

ery ow nor srupt on to pro uct on ne . e pro uct may a ve to esorte an a port on( ess t an )rewor e . t

n s quea ratt e tem oes not con rm . e ect not ce ymos cus omers.

nor nor crupt on to pro uct on ne. e pro uct may ave too e

sorte an port on ( ess t an ) rewor e on- ne ut out ostat on. t n s squea ratt e tems oes not con orm . e ectno ce y a scr m na ng cus omers.

ery nor srupt on to pro uct on ne . e pro uct may ave to enor sorte an port on ( ess t an ) rewor e on- ne ut n-

stat on . t n s squea ratt e tem oes not con orm . e ectno ce y a scr m na ng cus omers

one o e ect

Generic PFMEA OccurrenceDana Quality Assurance Services


CpK Ranking

Very High : Failure is almost inevit > 1 in 2 < 0.33 10

i

Probablity OF Failure Possible Failure Rates


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1 in 3 > 0.33 9

High : Generally Associated with processessimilar to previous processes which 1 in 8 > 0.51 8

often failed

1 in 20 > 0.67 7

Moderate : Generally associated with

processes similar to previous proces 1 in 80 > 0.83 6

which have experienced occasional

failures ,but not in major proportion 1 in 400 > 1.00 5

1 in 2000 > 1.17 4

Low: Isolated failures associated wi 1 in 15000 > 1.33 3

similar processes.

Very Low: Only isolated failures 1 in 150000 > 1.50 2

associated with almost identical

Processes.

Remote : failure Unlikely .No Failu < 1 in 1500000 >/1.67 1

associated with almost identical

processes

If a process is under SPC or is similar to previous process process under SPC ,then the Statisticaldata should be used to determine Occurrence ranking.

Assessment of occurrence ranking can be made using the word descriptions in the evaluation

creteria if statistical data is not available.

Detection Criteria : Liklyhood the existence of a defect will be Ranking

Generic PFMEA Detection



detected by process controls before next or subsequent

process, or before part or component leaves

manufacturing or assembly location

Al t N K C t l il bl t d t t f ili d 10


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Almost No Known Controls available to detect failiure mode 10

ImpossibleVery Very remote likelyhood current controls will detect failure mode 9

Remote

Remote Remote likehood current controls will detect failure mode 8

Very Low Very low .likelyhood current controls will detect failure mode. 7

Low Low likelyhood current current controls will detect failure mode. 6

Moderate Moderate likelyhood current controls will detect failure mode 5

Moderately Moderately likelyhood current controls will detect failure 4

High mode

High High Likelyhood current controls will detect failure mode. 3

Very High Very high likelyhood current controls will detect failure mode. 2

Almost Current Controls almost certain to detect the failure mode 1

Certain reliable detection controls are known with similar processes.

Assume the failure has occurred and then assess the capabilities of all current controls to prevent

shipment of the part having this failure mode or defect.

Random quality control checks would be unlikely to detect the existence of an isolated defect and

therefore would result in low to remote detection ranking.

Sampling done on an statistical basis is a valid detection control.

A reduction in detection ranking can only be achieved by improving process control system(s).

Process Failure Causes



1 Omitted processing 11 Poor control procedures

2 Processing errors 12 Improper equipment

3 E i k i i


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3 Errors setting up work pieces maintenance

4 Missing parts 13 Bad recipe

5 Wrong parts 14 Fatigue

6 Processing wrong work p 15 Lack of saftey

7 Mis-operation 16 Hardware failure

8 Adjustment error 17 Failure to enforce controls

9 Equipment not set proper 18 Envirnoment

10 Tools and /or fixtures 19 Stress connections

improperly prepared 20 Poor FMEA(s).

1 Standardized work instructions /procedures

Process Control Examples



2 Fixtures and jigs

3 Mechanical interference interfaces Controls can be

4 Mechanical counters process controls fool

5 M h i l fi PSC


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5 Mechanical sensors proofing or PSC ,or

6 electrical /Electronic sensors can be post -process7 Job sheets or process pacakages inspection/testing.

8 Bar coding withj software integartion and

control Inspection /testing

9 Marking may occur at the

10 Training and related educational safegaurds subject operation or

11 Visual Checks at subsequent

12 Gauge studies operations that can

13 Preventive Maintenance detect the subject

14 Automation (Real Time Control ) failure mode.

SPC records

Typical Process Documents



Visual aides

Work instructions


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Inspection instructions /recordsEquipment operating instructions

Training records

Traceability records

Corrective Action should be first directed at the highest

concerns as rank ordered by RPN.

Recommended Actions



The intent of any recommended action is to reduce the

occurrence ,severity and/or detection rankings.

If ti d d f ifi th thi


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If no actions are recommended for a specific cause ,then this

should be indicated.

Only a design revision can bring about a reduction in the

severity ranking.

To reduce the probability of occurrence ,process and/or

specification revisions are required.

To increase the probability of detection ,process control and /or

inspection changes are required .Improving detection controls is

typically costly.The emphasis should be placed on preventing,

rather than detecting ,defects.




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FTA

Inductive logic (bottom up) Deductive (top Down)

Determines all possible way gdbgbndgnbd

equipment can fail .Determines the Assumes a system failure and

effect of such failures on the system. determines the possible causes

FMEA

FMEA vs FTA



Focus is on the parts of which the Focus is on the total system

system is comprised


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The ellipseThe top event ,the ellipse contains the descrption of the system-level fault or

undesired event.The symbol appears at the head or top of the the tree and is

included on by once I any tree.The input to the ellipse is from a logic gate.

The Rectangle

Fault Tree Symbols



The fault event ,the rectangle , contains a brief descriptiuon of a lower level fault

This decriptiom should be short without being vague.Fault events appear

throughout the tree and have both their input and output from a logic gate.


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Logic Gates

Logic Gate inputs and outputs ,except for the inhinitgate,which is addresses

below ,have similar connections. The out put from a logic gate is to any fault

event block or to a transfer out function.The input is from any fault event block

or from a transfer in function.The AND Gate is the logic gate in which the

output occurs only if all inputs exist.

The or is thelogic gate in which the output occurs only if one or more of

the input events occur.

1 Defining the Undesired Events (Major Faults)

a) The undesired event is often the fault which ,upon occurrence ,results incomplete failure of the system,the failure of a back -up system ,degradation or

an undetected failure .This is considered catasophic failure.The major fault is

a failure which causes loss of availability through the degradation or system

shut down and/or poses a saftey hazard to operators and/or maintanence

personnel .The undesired event however ,may be unusual failure at a sub-

Fault Tree Fundamentals



system level ,the root caue of which is unknown .Any observable event may be

chosen as the "undesired event" .The analayst must recognise that the FTA will

not identify failures unrelated to the chosen event.


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b. To define the undesired event ,the normal system operation and envirnomentmust be known in order to allow the analysis to show the undesired event as a

failure .When defining the undesired event,are must be taken to prevent the

range of the faults from becoming too broad .For example ,Failure to complete

trip " for an automobile, is not specific enough to allow for ease of analysis .This

is because failure could vary from an air conditioning fault ,which caused

discomfort ,to loss of engine power ,which caused loss of mobility .Both faults

could be considered failure : however ,loss of mobility is obiviously a much more

severe fault than losing air conditioning.

2 Defining Types of Faults

Faults fall into two basic categories : operational and Component

Operation Fault

The operational fault is one which occurs when a component is operating as it

was designed to ,but at an inappropriate time or place .An example is a failure of

a control valve to close or to interruypt the introdiuction of a reactant into a

chemical process due to an inappropriate signal from another device.




Component Fault

The component fault can be further decided into two sub categories primary and


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The component fault can be further decided into two sub categories , primary and

secondary .a primary component fault occurs when a component fails to

function in its intended envirnoment .Example : A radar unit designed for use in

aircraft which fails due to vibration .a Secondary component failure occurs when

a componnet fails to function in an envirnoment other than the envirnoment for

Which it is intended ,Example : A radar unit designed for a cargo aircraft fails in a further aircraft

3 Comparision of Fault Occurrence and Faulty Existence

The term Fault Occurrence refers to the fact that an undesired event has taken

place and may or may not still exist .Fault Existence ,however implies that the

place and may or may not still exist .Fault Existence ,however implies that the

fault has occurred and continues to exist .Therefore the fualt can be describeas being either transient or permanent.

During the construction of the fault tree ,all systems analyst should use Fault

Occurence ,rather than Fault Existence as the focus of interest.




4 Comparison Of Failure Causes and Fault Effects

A failure is considered to be an ability to perform a normal fucntion Example:

Valve does not open .A Fault is a higher Occurrence which is usually

preceded by a lower -level failure such as a casing cracking due to overheating


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preceded by a lower -level failure,such as a casing cracking due to overheating

because of a lack of coolant induction due to an inoperable valve (lower level ogf

Failure ),However , a fualt may also occur when no failure is present .Example :

Coolant valve operates properly,but the signal to operate it encounters a delay

A Fault has occurred ,but there is no valve failure .Becuase of this ,it can be

stated that any failure causes a faulktr ,but not every fault is caused by a failure.

Failure Categories : a Component B.Envirnoment c.Human .D Software

Determine the level to which the examination should

be constructed

Begin with the system-level fault

Fully describe all events which immediately cause

this event

Fault Tree construction Steps Summary



With each lower -level; fault , continue describing its

immediate causes until a component level failure or


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immediate causes until a component level failure or

human error can be attributed to the fault

Fully define each branch of the tree before begining

another branch

During the construction of the tree ,it is advisable touse a block diagram of the system to simply

determining the main branches

Fault Tree Construction Steps Summary



If the results of the FMECA on the system are

available at the time of the FTA it is advisable to use


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the results in defining the top events

1 Determine the minimal cut-sets to simplify the tree

(Qualitative analysis ).

2 Determine the probability of each input event

3 Combine the probability inputs to logic gates asfollows :

a. AND Gate - The probability of output is the product of the

Analyzing the Fault Tree



probabilities of the inputs (Po=PI1Pi2..Pin)

b. OR Gate - The probability of output is the sum of the


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probablities of the inputs (Po=Pi1+Pi2.Pin)

4 Combine the gate input probablities until the

probablity of the top event is determined.

Identify the system or equipment level

fault state (s) (Undersed event(S))

Construct the fault tree

Perform the analysis to the component

level

Fault -Tree Analysis Procedures




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The top event must be measurable and

definable

The top event must be inclusive of the lowerevents

The top event is the result of the lower

Criteria for Identifying the undesired Event



events


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Can any equipment failures contribute to this effect?

Materials faults ?

Human errors?

Methods and Procedures?Software performance ?

Maintenance errors or the absence of maintenance ?

Inaccuracies or malfunctions of measurement

Clues About Causes



devices(s)?

Envirnoments such as chemicals ,duct ,vibration,


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shock and /or temprature?

Almost all errors are caused by human errors

Forgetfulness- Sometimes we forget things when we are not

concentrating .Example : A person forgets to set his /her alarm

close at night .Safegaurd establish a routine which include

checking before going to bed.

Errors due to misunderstanding - Sometimes we make

mistakes when we jump to wrong conclusion before we are

familiar with the situation .Example : A person used to a stick

Errors 1



shift pushes the brake petal in an automatic thinking it is the

clutch .Safegaurds : Training , checking in advance ,

standardizing work procedures .


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Errors in identification - Someties we misjudje a situation

because we view it too quickly or too far away to see it

clearly .

Safegaurds : Training ,attentiveness ,vigilane.

Errors made by amateurs - Some times we make mistakes

through lack of experience .Example : A new worker does not

know the operation or is just barely familiar with it .Safe gaurds :

Training ,Skill buliding work standerdization.

Willfull errors - Sometimes errors occur when we decide that

we can ignore the rules under certain circumstances .Examples "

Crossing a street against a red light because we no cars

Safe gaurds : Basic eductaion \Experience.

Inadverant errors- Sometimes we are absent minded and

Errors 2



make mistakes without knowing how they happened .Example:

Someone lost in thought tries is red or not .Safegaurds:

Attentiveness ,discipline Work standardization.

E d t l S i k i k h


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Errors due to slowness - Sometimes we make mistakes whenour actions are slowed down by delays in judjement .Example

A person learning to drive is slow to step on the brake .

Safegaurds : Skill buliding ,Work standardization.

Errors due to lack standards- some errors occur when

there are suitable instructions or standards .Example :

A measurement may be left to an individuals disdretion.

Safegaurds : Work standardization , Work instructions.

Surpirse errors- errors sometimes occur when equipment runs

differently than inspected .Example : A machine malfunction

without warning ,Safe gaurds : Total Productive MaintenanceWork Standardisation.

Surprise errors- Errors sometimes occur when equipment runs

differently than expected .Example : A machine malfunction

without warning .Safe gaurds : Total Productive Maintenance

work Standardization.

Errors 3



Intentional errors- Some People make mistakes deliberately

crimes and sobtage are examples Safe gaurds : Fundamentals

eductaion , Disiclipilne .

Mistakes happen for many reasons , but almost all

b t d if t k ti id tif h d


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can be prevented if we take tie identify when and

why they happen and then take steps to prevent

them, by using Poka -Yoke methods with

consideration to another available safe gaurds.

Variation control using assembly aidsIdentification by visual techniques

Standaredization work and work placce

organisation

Self - Check (In- process)Poke - Yoke

Five /methods of Mistake - proofing




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Emphasizes Prevention

Principles

Build into processes

Eliminate inadverant errors

Stop doing inadverant errors

Stop doing it wrong - Do it Right

Work TogetherFind Together

Find True Cause

Examples

Guide for part (Fixtures)

Mistake - Proofing




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Error detection alarm

Limit switchCounter

Check List




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Responsibility Responsibility activity

actvity

Dana Quality Assurance ServicesF il M d Eff ti A l i 10


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lity,reliability and durability significance .

expected performance of a product , unfavorably affect customer.




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Failure Mode and Effective Analysis

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Transcript of Failure Mode and Effective Analysis