Correlation Between DFMEA and Process Capability at Automotive Part Supplier - 24 Pages

8/19/2019 Correlation Between DFMEA and Process Capability at Automotive Part Supplier - 24 Pages

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ABSTRACT

This research is about the Design FMEA study in Automotive Part Supplier

Company. FMEA are stands for Failure Mode Effects Analysis which the

methodology of FMEA was used to identify the potential failure of a system and its

effects. And it also used to assess the failures to determine actions that wouldeliminate the change of occurrences. The selected automotive part supplier company

for this study is a Madetill (M) Sdn. Bhd at Balakong, Selangor. Through the

objective of the study, is to identify the correlation between FMEA and Cpk and also

develop a framework relationship between DFMEA and Process Capability. The

framework was created as a guideline to help Madetill company when they encounter

a problem and can used as a standard tooling to reduce the major problem. The

framework shows how the DMAIC help the company to settle the problem.

Framework also gives confident because FMEA was famous technique in automotive

supplier and will use to continuous quality improvement. Therefore, do the literatures

review to identify the several approaches of Design FMEA and process capability

implementation that applied at industries. In the literature review also look at the

some of the main Design FMEA projects, the major benefits are gained and the

DFMEA approach used. At the end of this research, the correlation between FMEA

and Cpk was can be done based on Occurrences.


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ABSTRAK

Penyelidikan ini berkisarkan kajian rekabentuk FMEA yang digunakan pada Syarikat

Pembekal alat ganti kenderaan. FMEA adalah singkatan dari ‘ Failure Mode Effect

Analysis’ di mana metodologi FMEA digunakan untuk mengenalpasti potensi

kegagalan sistem dan kesannya. Ianya juga digunakan untuk menilai kegagalan danseterusnya menentukan tindakan yang akan diambil bagi mengatasi masalah tersebut.

Syarikat Pembekal alat ganti kenderaan yang dipilih adalah Madetill (M) Sdn. Bhd di

Balakong, Selangor. Tujuan kajian adalah untuk mengenalpasti hubungan antara

FMEA dan CPK dan juga mencari persamaan dan hubungan diantara DFMEA dan

‘Process Capability’dan membuat rangka kerja. Rangka kerja ini dibuat untuk

membantu syarikat Madetill ketika mereka menghadapi masalah dan boleh

digunakan sebagai alat bantuan untuk mengurangkan masalah utama. Rangka kerja

ini menunjukkan bagaimana DMAIC membantu syarikat untuk menyelesaikan

masalah. Rangka kerja juga memberikan kepercayaan kepada syarikat kerana FMEA

adalah teknik terkenal di gunakan oleh pembekal automotif dan akan digunakan

secara berterusan untuk meningkatkan kualiti.


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DEDICATION

For my beloved family and friends for their loves and supports.


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ACKNOWLEDGEMENT

Several people played an important role in the accomplishing of this thesis and I

would like to acknowledge them here. First of all, I want thank to Almighty God for

reasons too numerous to mention. I also would like to thank to PM Dr Chong Kuan

Eng, my supervisor for the support and encouragement to pursue to this thesis andalso for the invaluable guidance he has provided. All the knowledge that he gives me

will helpful to my future. I also wish to give a special gratitude to Mr Ariazizi,

Executive production at Madetill (M) Sdn. Bhd, the company that the case study

were conducted and also his effort to help me in data collection for use in this study.

Without him, this thesis would have been most difficult. Besides, thanks also to my

parents for their financial supports along case study progress. Last but not least, I

would like to thank to my friends, for their comments and suggestions to improve the

quality of my thesis.


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TABLE OF CONTENT

Abstract i

Abstrak ii

Dedication iii

Acknowledgement iv

Table of Content v

List of Tables vii

List of Figures ix

List of Abbreviations x

1.0 INTRODUCTION 1

1.1 Background of study 1

1.2 Problem Statement 2

1.3 Objectives 2

1.4 Scope 3

1.5 Report outline 3

2.0 LITERATURE REVIEW 4

2.1 Introduction 4

2.2 FMEA 4

2.2.1 Purpose of FMEA 4

2.2.2 History of FMEA 5

2.2.3 Types of FMEA 6

2.2.3.1 Design FMEA 6

2.2.3.2 Process FMEA 7

2.2.3.3 System FMEA 7

2.2.3.4 Service FMEA 8

2.2.3.5 Software FMEA 8

2.2.4 Timing 8

2.2.5 Benefits of FMEA 10

2.2.6 FMEA RPN 11


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2.2.6.1 Severity 12

2.2.6.2 Occurrences 13

2.2.6.3 Detection 14

2.2.7 Inputs, Outputs and Other Quality Tools Related 15

2.2.7.1 Input to FMEA 15

2.2.7.2 Output from FMEA 15

2.2.7.3 Other Quality Tools related to FMEA 16

2.3 Design FMEA 17

2.4 Statistical Process Control 19

2.4.1 The basic tools for SPC 21

24.2 The benefits of SPC 22

2.4.3 Real benefits of SPC in organizations 22

2.5 Process Capability 23

2.5.1 Concept of Cpk 25

2.5.2 Relative of capability 26

2.6 DMAIC 27

2.6.1 Define 28

2.6.2 Measure 28

2.6.3 Analyze 29

2.6.4 Improve 29

2.6.5 Control 29

2.7 Conclusions 30

3.0 METHODOLOGY 31

3.1 Introduction 31

3.2 Phase I (Conceptual phase) 33

3. 2 Phase II (Implementation) 34

3.2.2 DMAIC Methodology 35

3.2.3 Define 36

3.2.4 Measure 36

3.2.5 Analyze 36

3.2.6 Improve 36

3.2.7 Control 37


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3.3 Phase III (Conclusion) 37

4.0 COMPANY BACKGROUND 38

4.1 Organization Profile 38

4.2 Company Policy 39

4.3 Company Details Profile 40

4.4 Vision and mission 40

4.6 Company MOTTO 41

5.0 RESULTS & DISCUSSION 42

5.1 Group of FMEA 42

5.2 Define (DMAIC) 43

5.3 Measure (DMAIC) 44

5.3.1 Generate RPN number 44

5.3.2 Dimension each part 47

5.4 Analyze (DMAIC) 48

5.4.1 Analyze each dimension 48

5.4.2 Revised RPN Number 49

5.4.3 Cpk vs. Occurrences 50

5.5 Improve (DMAIC) 53

5.5.1 Result Correlation between Cpk and Occurrences 53

5.5.2 Status of correlation between Cpk and Occurrences. 54

5.6 Control (DMAIC) 56

6.0 CONCLUSION 57

REFERENCES 58

APPENDICES

A Gantt chart PSM 1

B Gantt char PSM 11

C Group FMEA

D Data from MDT


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LIST OF TABLES

2.1 Table of severity in FMEA 12

2.2 Table of Occurrence in FMEA 13

2.3 Table of Detection in FMEA 14

2.4 SPC definition 20

5.1 Table of Define a Car Jack problem 43

5.2 Table of 1st FMEA 45

5.3 Table of dimension 475.4 Table result of SPC software 48

5.5 Table of revised RPN number 49

5.6 Occurrences status 50

5.7 Rating of Occurrences 51

5.8 Correlation between Cpk and Occurrences 52

5.9 New ranking of Occurrences 53

5.10 Status of correlation between Cpk and Occurrences 54

5.11 FMEA result 55


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LIST OF FIGURES

2.1 Design development stages 9

2.2 Sources at CCBG from Roger Lee 27

3.1 Research methodology 32

3.2 Research methodology (Phase I) 33

3.3 Research methodology (Phase II) 34

3.4 DMAIC methodology 35

3.5 Research methodology (Phase III) 37

5.1 Framework CQI for relationship between DFMEA and Process Capability 56


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LIST OF ABBREVIATIONS

Cpk - Process Capability

DFMEA - Design Failure Mode Effects Analysis

DMAIC - Define, Measure, Analyze, Improve, and Control

FMEA - Failure Mode Effects Analysis

MP - Mass Production

PFMEA - Process Failure Mode Effects Analysis

PP - Pre Production

TP - Test ProductionMSD - Madetill (M) Sdn.Bhd

Dim - Dimension

SD - Standard Deviation

USL - Upper Specification Limit

LSL - Lower Specification Limit

Spec - Specification

RPN - Risk Priority Number

C&E - Cause and effect diagram

SPC - Statistical Process Control

CQI - Continuous Quality Improvement


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CHAPTER 1

INTRODUCTION

1.1 Background of study

FMEA is stands for Failure Mode Effects Analysis which the methodology of FMEA

was used to identify the potential failure of a system and its effects. And it also used to

assess the failures to determine actions that would eliminate the change of occurrences.

Normally in industries, FMEA is applied during the initial stage of designing process

development. In FMEA there are many types of FMEA.

Hence, this study will be focused on Design FMEA which analyse on failures in current

design (performance, functional, design) and detection of the failure which concentrate

on dimensional items of the products for automotive industries. Meanwhile, process

capability is an ideal process as well as target for production. In the quality system,

Process Capability (Cpk) is the important key performance indexes (KPI) to ensure

process producing a good product follow the customer specification. DMAIC define as

(Define, Measure, Analyse, Improve, Control) will be used to integrated Design FMEA

and Process Capability (Cpk) in this study as well as a system to enhance product

quality performance.


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1.2 Problem Statement

Nowadays, in design process, it is difficult to identify which part of dimension that is

important and not important. The important dimension normally knows as critical

dimension because it can give effect for function user and cause failure to the product

performance. Critical dimension decide by customer but there are no standard method to

determine the critical dimension. Besides that, there was no study initial stage on that. In

each product, there are many dimensions in one part. So each part must be checked

based on part drawing. This is wasting of time and high cost for labor because there are

a lot of dimensions and some of the dimensions are not important to check. In this case,

it is difficult to decide the important dimension because there was no standard flow to

determine the parameter. During industrial study in FMEA studies, there is no standard

approach to link between FMEA and process control.

1.3 Objectives

To describe more details about this study, the objective was stated here to give a more

comprehension to the problem statement. Basically, in this part, the objective will

clearly define that purpose to shown the framework and explains what to do next. An

objective of this study is:

i) To find correlation between DFMEA and Process Capability

ii) To develop a framework of continuous quality improvement (CQI) for

relationship between DFMEA and Process Capability


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1.4 Scope

This study will thoroughly focus on correlation between Design FMEA and Process

Capability analysis for dimensional only which selected during new model development.

The dimension of part is very crucial since it will affect assembly process and product

performance. In this research, a manufacturing company will be selected to implement

this project which this company will supply products or part to automotive assembly

industries. DMAIC methodologies will be use as a guideline in this research. DMAIC

define as (Define, Measure, Analyse, Improve, and Control).

1.5 Report Outline

Chapter 1: Introduction

• This chapter briefly explained the background of the project study, the objective

that want to achieved, the problem statement and finally whole project through

Gantt chart.

Chapter 2: Literature Review

• This chapter was collection of research information that relate to the study from

any trusted resources.

Chapter 3: Research Methodology

• This chapter explains the structure on how project was done.

Chapter 4: Background Company

• This chapter introduces and explains about company profile that we choose to

complete this research.


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CHAPTER 2

LITERATURE REVIEW

2.1 Introduction

This chapter part was specifying the review of source and history related information

about FMEA. Generally, literature review is a critical analysis segment which sources

from books, journal, article, reports and major on the knowledge related with summary,

and comparison of research studies, reviews of literature and theoretical articles. It also

will explain about methods and tools of DFMEA which generally used in various fields

and the related theory in this research.

2.2 FMEA

2.2.1 Purpose of FMEA

The acronym FMEA, for readers who are less familiar, stands for Failure Modes,

Causes, and Effects. FMEA is a systematic analysis of potential failure modes aimed at preventing failures. FMEA can be described as a tool for evaluating potential failures

and the related causes and resultant effects in a six sigma process. This is intended to be

a preventative action process carried out before implementing new or changes in

products or processes from reaching the customer and to assure the highest possible


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yield, quality and reliability. FMEA is used to prioritize potential failures, in order of

their severity, and attempts to minimize, if not totally eliminate, the probability of such

failures happening.

In industry, have a lot of reasons why the organization wish to use FMEA. There are

companies that use FMEA selectively to sort out a specific problem. Then there are

companies with vision who wish to use FMEA more as a preventive measure to forestall

likely failures. Some manufacturing companies opt for FMEA more as a company

policy to constantly monitor and ward off or lessen failure potential.

Tay and Lim (2006) explained that according to Chrysler Corporation et al. (1995),

FMEA can be described as a systemized group of activities intended to recognize and to

evaluate the potential failures of a product/process and its effects. Besides, FMEA

identifies actions which can eliminate or reduce the chances of potential failures from

recurring. It also helps users to identify the key design or process characteristics that

require special controls for manufacturing, and to highlight areas for improvement in

characteristic control or performance (Ireson et al., 1995).

2.2.2 History of FMEA

FMEA was developed in the United States Military. Military Procedure MIL-P-1629,

titled Procedures for Performing a Failure Mode, Effects and Criticality Analysis, in

November 9, 1949. At that time it was used as a reliability evaluation technique to

determine the effect of system and equipment failures. The failures were classified

according to their impact on mission success and personnel or equipment safety. Yang,

Lin, Lin and Huang (2006) explained that in 1977, Ford Motor Company announced the

operation standards of FMEA for promotion and application in the education manual

(Ford, 1988), which was adopted by other motor companies one after another and

further divided into Design FMEA and Process FMEA.


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In addition to FMEA implemented inside a company, suppliers were asked to conduct

design and process FMEA for the parts they supplied. In 1985, International Electronic

Commission (IEC) published FMEA standards for system reliability. IEC812 is the

modified FMEA operational procedures based on MIL-STD-1629A expounding FMEA

for electronic, mechanical and hydraulic equipment or parts. Besides, it also mentioned

the applicability of FMEA to software and personnel reliability analyses. The failure risk

evaluation method in the education manual of Ford Motor Company is the most

traditional and has been generally adopted by all walks of life currently. The data of risk

priority number (RPN) are based on risk assessment. The multiplied risk factor indices

refer to Severity (S), the outcome of a failure, Occurrence (O), the chance of a failure

and Detection (D), the chance of a failure is not detected by customers or the difficulty

level of detection (Tables I-III). A scale of ten-points is served to be a comparison table

for the level and grade of these three factors. RPN is the outcome of multiplying

occurrence, detection and severity and can be represented as Formula 1. For the decision

factor number of RPN, different decision factors and grades judgment principles can be

formulated in accordance with FMEA applications.

2.2.3 Types of FMEA

There are several types of FMEA; some are used much more often than others. The

types of FMEA are design, process, service, system and software. Process and design

are the most common use in industry.


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2.2.3.1 Design or FMEA

Design FMEA is used to analyze products before they are released to production. It is

focuses on potential failure modes of products caused by design deficiencies. It is also

helping to identify potential safety concerns so products design can be identified to

eliminate the concerns.

2.2.3.2 Process of FMEA

Which is used for manufacturing and assembly processes. Process FMEA is focused on

problems from how the equipment is manufactured, maintained or operated. Process

Failure Mode and Effects Analysis (PFMEA) is a method to assess production processes

weaknesses and potential effects of process failure on the product being produced.

Process FMEA emphasizes the importance of actions that can be taken to eliminate or

reduce the potential causes leading to the process failures. However, it has been

observed that manufacturing engineers are too occupied with how to make things work

and thus fail to consider the potential pitfalls. Thus, it is imperative that Process FMEA

is conducted throughout the process and should be revised whenever a change has been

made to it. Process FMEA ensures that the manufactured products are met with the

engineered product specifications and that the process defects do not result in product

safety problems in the field.

2.2.3.3 System of FMEA

Which is used for global systems, System FMEA looks for potential problems and

bottlenecks in larger processes, such as entire production lines. A system FMEA usually

is accomplished through a series of steps to include conceptual design, detail design,

development, test and evaluation. The design in this phase is an evolutionary process

involving the application of various technologies and methods to produce an effective

system output. The results will be used as an input for the design FMEA. The focus in


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this stage is to transform an operational need into a description of system performance

parameters and as perfect as possible system configuration through the use of an

interactive process of functional analysis, synthesis, optimization, design, test, and

evaluation

2.2.3.4 Service FMEA

This is used for services industry. The importance of actions that can be taken to

eliminate reduce the potential causes leading to the service failures or. The field of

service includes bank, hospital, and supermarket and so on.

2.2.3.5 Software FMEA

Failure mode and effects analysis (FMEA) software is used to track trends, generate

statistics such as mean time between failures (MTBF), and determine the root causes of

field failures (usually for products covered by a manufacturer’s warranty).

2.2.4 Timing

Initially, the FMEA should be performed while in the design stage, but it also may be

used throughout the life cycle of a product to identify possible failures as the system

ages. Failure mode and effect analyses may vary in the level of detail reported,

depending upon the detail needed and the availability of information. Normally In

industry, FMEA applies as below;


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Attend concept meeting for new

model and discuss about new

parts

Check the proto drawings and

discuss with designer based on

proto drawings. Hold the tooling

discussion meeting

Monitor tooling progress and

approval schedule, approve the

new parts for TP using.

Monitor tooling modification and

design change progress and

approval schedule and using

Design FMEA.

Approve the parts and apply

Process FMEA

Figure 2.1: Design development stages (Sources from TDK_Lambda Sdn.Bhd)


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2.2.5 Benefits of FMEA

The FMEA programmer offers a wide range of benefit for the organization which

implemented it. The several benefits that can be described are:

i. Minimizes late changes and associated cost since FMEA is been carried out

during design stage.

ii. Identifies failure modes which will have significant impact

iii. Identifies the causes of failures and minimizes them

iv. Helps in redesigning to reduce the effect of failures

v. Improve product reliability, maintainability and availability of the system

vi. Increases customer satisfaction

vii. Prioritize product / process deficiencies for improvement

viii. Emphasizes problem prevention

ix. Providing information of:

• Maintainability analysis

• Safety analysis

• Survivability

•

Vulnerability• Logistic support analysis

• Maintenance plan analysis

• Risk analysis

• Failure detection


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2.2.6 FMEA RPN

Risk Priority Number (RPN) is a measure used when assessing risk to help identify

critical failure modes associated with your design or process. The RPN values range

from 1 (absolute best) to 1000 (absolute worst). The FMEA RPN is commonly used in

the automotive industry and it is somewhat similar to the criticality numbers used in

Mil-Std-1629A. Risk priority numbers (RPN) for the parameters are calculated by

multiplying severity (S) by occurrence (O) and detection (D) (S x O x D).


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2.2.6.1 Severity

Severity is the factor that represents the seriousness or impact of the failure to the

customer or to a subsequent process. Severity of failure relates to process failure effects

and is independent of occurrence and detection. Severity of a failure effect is therefore

the same for all failure causes. Severity should be considered as though no controls are

in place.

Table 2.1: Table of severity in FMEA

Effect Severity of Effect Ranking

Hazardous-

without warning

May result in safety issue or regulatory violation with

warning10

Hazardous-with

warningPrimary function is lost or seriously degraded 9

Very High Primary function is reduced and customer is impacted 8

High Secondary function is lost or seriously degraded 7

Moderate Secondary function is reduced and customer is impacted 6

LowLoss of function or appearance such that most customers

would return product or stop using service5

Very LowLoss of function or appearance that is noticed by customers

but would not result in a return or loss of service4

MinorLoss of function or appearance that is noticed by customers

but would not result in a return or loss of service3

Very Minor

Loss of function or appearance that is unlikely to be noticed

by customers and would not result in a return or loss of

service

2

None Little to no impact 1

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Correlation Between DFMEA and Process Capability at Automotive Part Supplier - 24 Pages