DESIGN AND DEVELOPMENT OF THERMODYNAMICS APPARATUS
USING DESIGN FOR MANUFACTURE AND ASSEMBLY (DFMA)
METHODOLOGY
WAN ABD. RAHMAN ASSYAHID BIN WAN IBRAHIM
A project report submitted in partial fulfillment of the
requirements for the award of the degree of
Master of Mechanical Engineering
(Advance Manufacturing Technology)
Faculty of Mechanical Engineering
Universiti Teknologi Malaysia
MAY, 2006
v
ACKNOWLEDGEMENTS
I wish to express my sincere appreciation to my thesis supervisor, Tuan Haji
Dr. Ariffin Bin Abdul Razak, for encouragement, guidance, critics and friendship.
Without his continued support and interest, this thesis would not have been the same
as presented here.
Special thanks must go to Ahmad Humaizi Helmi and Ahmad Faizal Bin
Salleh for their truly support, co-operation and assistance. Thanks are also goes to
friends who had helped me directly or indirectly upon the project completion.
Finally, my very special, sincere and heartfelt gratitude goes to my beloved
wife and family for giving me tremendous courage while I was struggling with this
project. Their assistance and support was invaluable.
Wan Abd. Rahman Assyahid
May, 2006
vi
ABSTRACT
Thermodynamics is an essential subject in Mechanical Engineering
curriculum. The thermodynamics principles have been applied in many applications
to fulfill human needs. Mechanical engineers use thermodynamics principles in their
study to design a wide variety of energy system such as jet engines and rockets,
refrigeration system, air conditioning system, chemical process and power plant. This
would explain that thermodynamic was one of the critical areas which need to be
well understood. However, the majority of students perceive thermodynamics as a
difficult subject. By having the suitable experiment apparatus designed to
demonstrate thermodynamics process and system have been learned, such an
apparatus would enhance the teaching and learning of thermodynamics. Therefore,
an apparatus for this purpose is necessary to be developed. The apparatus should be
portable and mobilize which demonstration in both lecture and laboratory session is
possible. A Boothroyd-Dewhurst Design for Manufacturing and Assembly (DFMA)
Methodology had been applied to optimize the design apparatus. The application of
Boothroyd-Dewhurst (DFMA) Methodology will simplify the design through
minimizing the part component for ease of assembly and manufacture. In addition,
this methodology also provides analysis for selection of manufacturing process and
material for developed apparatus. Therefore, the overall development cost could be
minimized. The aim of this project is to successful develop an apparatus which could
demonstrate the 1st Law of Thermodynamics-closed system based on Boothroyd-
Dewhurst DFMA Methodology.
vii
ABSTRAK
Termodinamik merupakan salah satu mata pelajaran asas yang terpenting
dalam kurikulum kursus Kejuruteraan Mekanikal. Prinsip-prinsip termodinamik
diaplikasikan dalam penciptaan dalam pelbagai peralatan bagi kemudahan
kehidupan manusia. Jurutera mekanikal menggunakan prinsip termodinamik untuk
mereka bentuk pelbagai jenis peralatan seperti enjin jet dan roket, sistem
penyejukan/pendinginan, sistem loji pemprosesan kimia dan sistem loji penjanaan
tenaga. Hal ini menjelaskan bahawa bidang termodinamik merupakan satu bidang
yang amat kritikal dan amat perlu dikuasai dengan sebaik yang mungkin oleh para
pelajar. Akan tetapi sehingga kini, kebanyakan pelajar masih menganggap bidang
termodinamik adalah satu bidang yang amat sukar untuk dipelajari. Dengan adanya
alat ujikaji yang bersesuaian bagi menerangkan proses termodinamik yang dipelajari,
maka sessi pembelajaran akan menjadi lebih menarik dan berupaya memudahkan
pemahaman para pelajar. Justeru itu, satu alat ujikaji termodinamik wajar
dibangunkan. Alatan ujikaji yang dibangunkan ini adalah bersifat mudah alih yang
boleh digunakan untuk demontrasi dalam kuliah dan juga dalam makmal. Bagi
mengoptimum reka bentuk alat ujikaji ini, kaedah Reka bentuk untuk Pembuatan dan
Pemasangan (DFMA) yang dipelopori oleh Boothroyd-Dewhurst telah digunakan.
Kaedah yang diguna pakai ini adalah bertujuan untuk memudah dan meringkaskan
reka bentuk alat ujikaji ini dengan meminimumkan jumlah komponen bagi
memudahkan kerja pemasangan dan pembuatan. Pemilihan bahan proses pembuatan
juga dapat ditentukan melalui kaedah ini. Kesan dari aplikasi kaedah ini adalah kos
keseluruhan produk dapat diminimakan. Matlamat akhir projek ini adalah untuk
membangunkan satu alat ujikaji makmal yang menggunakan prinsip Hukum Pertama
Termodinamik sistem tertutup dengan menggunakan kaedah Reka bentuk untuk
Pembuatan dan Pemasangan (DFMA) yang diperkenalkan oleh Boothroyd-
Dewhurst.
viii
TABLE OF CONTENTS
CHAPTER TITLE PAGE
ACKNOWLEDGEMENT v
ABSTRACT vi
ABSTRAK vii
TABLE OF CONTENTS viii
LIST OF TABLES xiv
LIST OF FIGURES xv
LIST OF SYMBOLS xviii
LIST OF APPENDICES xx
1 INTRODUCTION 1
1.1 Introduction to the Problem 1
1.2 Objective of Project 2
1.3 Scope of Project 2
1.4 Project Methodology 3
1.5 Significant of Findings 5
1.6 Report Structure 5
1.7 Summary 7
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2 LITERATURE REVIEW 8
2.1 Introduction 8
2.2 Thermodynamics Systems and Boundary 9
2.3 The 1st Law of Thermodynamics 11
2.4 Energy Balance 11
2.5 Energy Change in System 12
2.6 Mechanism of Energy Transfer, Ein and Eout 14
2.6.1 Heat Transfer 14
2.6.2 Work 14
2.6.3 Mass Flow 15
2.7 1st Law of Thermodynamics in 15
Piston Cylinder Analysis
2.8 Product Development Process 22
2.9 Identifying Customer Needs 24
2.10 Product Design Specifications (PDS) 25
2.11 Engineering Design Process 26
2.12 Concept Generation 27
2.13 Concept Selection 29
2.13.1 Concept Screening 30
2.13.2 Concept Scoring 32
2.14 Design for Manufacture and Assembly (DFMA) 35
2.15 Overview of Design For Manufacture (DFM) 36
2.16 DFM Methodology 37
2.17 Boothroyd-Dewhurst DFM Methodology 38
2.17.1 General Shape Attribute 40
2.17.2 Process Capabilities 41
2.18 DFM Guidelines 42
2.18.1 Design for Ease of Fabrication 42
2.18.2 Design within Process Capabilities 42
2.18.3 Simplify the Design and
Reduce Parts Number 43
2.18.4 Standardize and use common
parts and materials 43
2.19 Overview of Design For Assembly (DFA) 43
x
2.20 DFA Methodologies 44
2.20.1 The Boothroyd-Dewhurst DFA Method 44
2.20.1.1 Theory of Evaluation 45
2.20.1.2 Evaluation Procedure 45
2.20.2 The Hitachi Assemblablility
Evaluation Method 49
2.20.2.1 Theory of Evaluation 49
2.20.2.2 Evaluation Procedure 50
2.20.3 The Lucas DFA Method 51
2.20.3.1 Theory of Evaluation 51
2.20.3.2 Evaluation Procedure 51
2.21 DFA Guidelines 53
2.21.1 Reduce Part Count and Part Types 55
2.21.2 Eliminate Adjustments 56
2.21.3 Self Locating and Aligning 56
2.21.4 Consider Handling Part from Bulk 57
2.21.5 Consider Ease for Handling 58
2.21.6 Eliminate Threaded Fasteners 59
2.21.7 Minimize Variations, Use Standard Part 59
2.21.8 Easy Serviceability and Maintainability 59
2.21.9 Minimize Assembly Directions 60
2.21.10 Provide Easy Insertion and Alignment 60
2.22 Summary 61
3 CONCEPTUAL DESIGN DEVELOPMENT 62
3.1 Introduction 62
3.2 User Requirements 63
3.3 Prepare Product Design Specification 64
3.4 Concept Generation 65
3.4.1 Concept No. 1 65
3.4.1.1 Concept Description 66
3.4.1.2 The Advantage and Disadvantage 67
3.4.2 Concept No. 2 68
3.4.2.1 Concept Description 68
xi
3.4.2.2 The Advantage and Disadvantage 69
3.4.3 Concept No. 3 70
3.4.3.1 Concept Description 70
3.4.3.2 The Advantage and Disadvantage 71
3.4.4 Concept No. 4 72
3.4.4.1 Concept Description 72
3.4.4.2 The Advantage and Disadvantage 73
3.5 Selection Criteria 74
3.5.1 Ease of Handling 74
3.5.2 Low Cost 75
3.5.3 Safety 75
3.5.4 Ease of Manufacture 75
3.5.5 Lightweight 76
3.5.6 Portability 76
3.5.7 Ease of Maintenance 76
3.6 Concept Screening 77
3.7 Concept Scoring 78
3.8 Final Concept Selection 80
3.9 Summary 81
4 DESIGN FOR MANUFACTURE AND
ASSEMBLY (DFMA) ANALYSIS 82
4.1 Introduction 82
4.2 Product Structure and Part Quantity 83
4.2.1 Assembly Drawing 84
4.2.2 Exploded Drawing 85
4.2.3 Bill Of Material (BOM) 86
4.2.4 Part Function and Critics 87
4.3 Boothroyd-Dewhurst DFM Analysis 90
4.4 Boothroyd-Dewhurst DFA Analysis 93
4.5 Apparatus Animation 96
4.6 Summary 97
xii
5 FABRICATION AND ASSEMBLY 98
5.1 Introduction 98
5.2 Development –Phase 1 99
5.2.1 Cylinder Liner 99
5.2.2 Piston 101
5.2.3 Cylinder Liner Cover 103
5.3 Development – Phase 2 103
5.3.1 Base Support 104
5.3.2 Cylinder Liner Support 105
5.4 Development – Phase 3 106
5.4.1 Cylinder Assembly 106
5.4.2 Thermometer Installation 108
5.4.3 Piston Indicator Assembly 109
5.4.4 Piston Installation 110
5.5 Complete Assembly 112
5.6 Summary 113
6 TESTING AND OPERATION WORK PROCEDURE 114
6.1 Introduction 114
6.2 Apparatus Preparation 115
6.3 Safety Instruction 117
6.4 Work Procedure 118
6.5 Data Collection 126
6.6 1st Law of Thermodynamics Analysis 128
6.6.1 Work Analysis, W 130
6.6.2 Total Internal Energy Analysis, �U 131
6.6.3 Net Heat Enter to System, Q 134
6.7 Summary 135
7 DISCUSSION 136
7.1 Introduction 136
7.2 Product Development Approach 137
7.3 Design For Manufacture and Assembly Methodology 137
7.4 Fabrication and Assembly 141
xiii
7.5 Apparatus Testing and Functionality 142
7.6 Summary 142
8 CONCLUSIONS 143
8.1 Conclusion 143
8.2 Recommendation And Future Work 144
REFERENCES 145
APPENDICES A1 - E 146 - 156
xiv
LIST OF TABLES
TABLE NO. TITLE PAGE
2.1 Example of customer needs for the suspension fork 24
2.2 Example of concept screening matrix 30
2.3 Example of concept scoring matrix table 32
2.4 Concept rating 33
2.5 Shape Generation Capabilities of Processes 41
2.6 Boothroyd-Dewhurst DFA Evaluation table 46
2.7 Evaluation table of old piston assembly 47
2.8 Evaluation table of new design piston assembly 48
3.1 Product Specification 64
3.2 Screening matrix 77
3.3 Relative performance rating 78
3.4 Concept scoring matrix 79
4.1 Bill of Material of developed apparatus 86
4.2 Part functions 87
4.3 Shape attributes and material requirement data for cylinder 91
4.4 Process elimination for cylinder 92
4.5 Alpha (�) and beta (�) angle for each part 94
4.6 Computation Design Efficiency of the apparatus 95
6.1 Work Procedure for operating the apparatus 119
6.2 Table for data record 127
6.3 Testing data 128
xv
LIST OF FIGURES
FIGURE NO. TITLE PAGE
1.1 Project flowchart 3
2.1 Close system 10
2.2 Open system 10
2.3 Piston cylinder apparatus 15
2.4 Lifting the piston by steam pressure 16
2.5 Concept development phase 22
2.6 Five steps of concept generation 28
2.7 Generation of new concepts of potato peeler 29
2.8 Design flow in DFM 37
2.9 Compatibility matrix between processes and materials 39
2.10 Old design of piston assembly 47
2.11 New design of piston assembly 48
2.12 Example of AEM symbols and penalty scores 50
2.13 Application of DFA guidelines 54
2.14 Part reduction using DFA guidelines 55
2.15 Self locating and aligning parts 56
3.1 Design Concept No. 1 65
3.2 Design concept No. 2 68
3.3 Design concept No. 3 70
3.4 Design concept No. 4 72
3.5 Final design concept 80
4.1 Product structure 83
4.2 Assembly drawing of final design concept 84
4.3 Exploded drawing of final design concept 85
xvi
LIST OF FIGURES – CONTINUED
4.4 Step 1, piston at rest position 96
4.5 Step 2, piston start lift-up 96
4.6 Step 3, piston still lifting 96
4.7 Step 4, piston reach to final position 96
5.1 Cylinder Liner 99
5.2 Flow Chart of Cylinder Liner Fabrication Process 100
5.3 The Piston 101
5.4 Piston after modification 102
5.5 Aluminum sheet 103
5.6 Base support 104
5.7 Two inches angle iron 104
5.8 Cylinder liner support 105
5.9 Cylinder liner before assembly 106
5.10 Cylinder liner after assembly 106
5.11 Cylinder liner after wrapping with woven 107
5.12 Cylinder liner after assembled with aluminum cover 108
5.13 Thermometer installation 108
5.14 The assembly of indicator on piston 109
5.15 Ring Expander 110
5.16 Piston and ring 110
5.17 Special tool to insert piston to cylinder liner 111
5.18 Method to insert piston into cylinder 111
5.19 Complete Assembly of Apparatus 112
6.1 Lubrication oil is applied on the cylinder liner inner wall. 115
6.2 Complete apparatus arrangement 116
6.3 Hot surface sign on cylinder liner 117
6.4 Hot surface sign on base support 118
6.5 Complete Apparatus 119
6.6 Checking all fittings 119
6.7 Applying lubrication oil 119
xvii
LIST OF FIGURES – CONTINUED
6.8 Close bottom valve 120
6.9 Water is filled to cylinder 120
6.10 Initial temperature 120
6.11 Initial pressure 121
6.12 Initial piston position 121
6.13 Butane gas weight measurement 121
6.14 Installation of Butane gas container to gas stove burner 122
6.15 Placing gas stove burner 122
6.16 Flame directed to bottom of cylinder liner 122
6.17 Observation of temperature increasing 123
6.18 Temperature at 90° C 123
6.19 Ready to shut down gas burner 123
6.20 Piston slowly lifts up 124
6.21 Shut down gas burner 124
6.22 Piston lift to new position 124
6.23 Final water temperature 125
6.24 Piston final position 125
6.25 Final Pressure 125
6.26 Measurement final butane gas weight 126
6.27 Illustration of experimental process 129
7.1 Percentage of theoretical minimum parts 138
7.2 Comparison between parts that need special tool to total part 139
7.3 Percentage of assembly time 139
xviii
LIST OF SYMBOLS
E1 = Initial energy
E2 = Final energy
Ein = Total energy entering the system
Eout = Total energy leaving from system
∆Esystem = Change in the total energy in the system
Efinal = Energy at final state
Einitial = Energy at initial state
∆U = Change in internal energy
∆PE = Change in potential energy
∆KE = Change in kinetic energy
m = Mass of system, kg
u2 = Specific internal energy at final state
u1 = Specific internal energy at initial state
V2 = Final velocity, m/s
V1 = Initial velocity, m/s
g = Gravity acceleration, m/s2
z2 = Final height, m
z1 = Initial height, m
Q = Heat supplied to system, Joule
W = Work done by system, Joule
X1 = Initial position, m
X2 = Final Position, m
P = Pressure, Pa
V = Volume, m3
A = Area, m2
F = Force, kg / ms-2 or Nm
xix
LIST OF SYMBOLS (CONTINUED)
vf = Specific volume: Saturated liquid, m3/kg
vg = Specific volume: Saturated vapour, m3/kg
vfg = Specific volume: Evaporation, m3/kg
uf = Internal energy : Saturated liquid, kJ/kg
ug = Internal energy : Saturated vapour, kJ/kg
ufg = Internal energy : Evaporation, kJ/kg)
v1 = Specific volume at initial state, m3/kg
v2 = Specific volume at final state, m3/kg
x = Quality
Cv = Specific heat of Ideal gas, kJ/kg
T1 = Temperature at initial state, ºC
T2 = Temperature at final state., ºC
xx
LIST OF APPENDICES
APPENDIX TITLE PAGE
A1 Gantt Chart for Semester 1 146
A2 Gantt Chart for semester 2 146
B1 Te Standard Thermodynamics Properties 147
Table for water
B2 Example of Product Design Specification 148
B3 General Capabilities of a range of commonly 150
used manufacturing processes.
C Data for estimated times for manual handling 154
(Boothroyd-Dewhurst)
D Data for estimated times for manual insertion 155
(Boothroyd-Dewhurst)
E Lucas DFA method - Manual Handling and 156
Manual Fitting Analysis
CHAPTER 1
INTRODUCTION
1.1 Introduction to the Problem
Thermodynamic is an essential subject in Mechanical Engineering
curriculum. The thermodynamics principles have been applied in many applications
to fulfill human needs. Mechanical engineers use thermodynamics principles in their
study to design a wide variety of energy system such as jet engines and rockets,
refrigeration system, air conditioning system, chemical process and power plant.
These would explain that thermodynamic was one of the critical areas which need to
be well understood. However, the majority of students perceive thermodynamics as a
difficult subject. Failure to understand the fundamental of thermodynamics will
result negative thinking toward the subject. A proposal to integrate between
thermodynamics theories and applications during learning process is one of the
solutions to avoid negative paradigms among the students. Therefore, an
experimental apparatus that applied thermodynamics theory is needed to be
developed. This project is carried out to design and develop an experimental
apparatus that can demonstrate thermodynamics theory. The aim of developing this
experimental apparatus is to integrate between theories learned in lecture room to the
real applications. The experimental apparatus had been developed is mainly focused
to demonstrate the 1st Law of Thermodynamics-closed system. Design for
Manufacturing and Assembly (DFMA) Methodology has been used during design
and development stages. The application of DFMA methodology during design and
2
development is to ensure the developed experimental apparatus is ease to
manufacture as well as ease to assemble in cost-efficient and at same time to achieve
higher product performance characteristics. As the end result, an experimental
apparatus is successful fabricated and ready to use in Thermodynamics laboratory.
1.2 Objective of Project
The objective of the project is to design and develop a portable experimental
apparatus based on the 1st Law Thermodynamics using Boothroyd-Dewhurst DFMA
Methodology.
1.3 Scope of Project
The scopes of the project are
1. Understanding the DFMA Methodologies for manual assembly.
2. Application of Boothroyd-Dewhurst DFMA during product assembly
analysis and manufacturing process selection.
3. The use of 1st Law Thermodynamics close system in the experimental
apparatus.
4. The use of water or gas as working fluid in experimental apparatus.
5. The animation of the proposed design using animation software.
3
1.4 Project Methodology
The project is conducted in two consecutive semesters which are summarized
in figure 1.1.
Figure 1.1: Project Flow Chart
Start
END
1st Semester
2nd Semester
Testing and evaluation/ improvement
Summary/Conclusion/Recommendation
Concept Selection
DFM Analysis of Final Design
DFA Analysis of Final Design
Problem Definition
Literature Review on Product Development / DFMA Methodologies and Thermodynamics
Prepare Product Design Specification
Concept Generation
Discussion
Part Preparation and Fabrication
Animation Preparation
4
The project is accomplished in two semesters. The milestones of project
activities are shown in Gantt chart in Appendix A1 for semester 1 and Appendix A2
for semester 2.
In the first semester, the project starts by carrying out a literature review on
product development process, continued with Design for Manufacture and Assembly
(DFMA) and end up with 1st Law of Thermodynamics theory. The DFMA
Methodologies that being discussed are the Boothroyd-Dewhurst DFMA, the Lucas-
Hall Evaluation Method, and the Hitachi Assemblability evaluation Method (AEM).
The development process continues by preparing Product Design Specification
(PDS). The PDS was a product specification that being generated based on user
requirements. The next task is to generate several design concepts, then to select the
final design concept using concept screening and concept scoring method.
Preparation assembly and exploded drawing is also done for DFA analysis. The
Boothroyd-Dewhurst DFMA analysis is used to obtain design efficiency also to
determine the product material and manufacturing process.
In second semester, the project continues with material preparation and
fabrication. The experimental apparatus then will be tested. The evaluation and
improvement is carried-out during product testing. Finally, the product performance
is discussed and recommendations for future improvement are proposed.
5
1.5 Significant of Findings
The aim of DFMA methodology is to simplify the design. In other word,
DFMA target is to minimize components in experimental apparatus. Minimizing the
components means fewer components per unit product. Fewer components will lead
to reduce the overall production cost. Therefore, the experimental apparatus is
expected to be ease of fabrication and assembly. In other perspective, the
experimental apparatus will help students to understand the thermodynamics theory.
As the final result, student’s performance will increase and students may not more
perceive thermodynamics as a difficult subject but they will find that thermodynamics
is one of the interesting subjects.
1.6 Report Structure
The report consists of eight chapters. Chapter 1 is about introduction to the
project. An overall picture of the project can understand within this chapter. The
objectives and scopes are explained, while the significant of the project is described
at the end of chapter.
Chapter 2, deals with a literature review on 1st Law of Thermodynamics,
Product Development Process and DFMA Methodology. In 1st Law of
Thermodynamics review, the analysis of piston cylinder within close system is
clearly overview. Related equations and data are also been provide. Then, a Product
Development Process is explain touching steps for systematic of product
development is process such as identifying user needs, then generating the concept
design is clearly overviewed. The review ends with the concept selection procedure.
In DFMA review, three methodologies is described such as Boothroyd-Dewhurst
DFMA, Lucas DFA and Hitachi AEM. However, the Boothroyd-Dewhurst DFMA
Methodology is explained in details. The chapter concludes with a DFA guidelines
during product development process.
6
Chapter 3 focuses on the development process of the experimental apparatus.
This chapter starts with the user requirements, followed by preparation of Product
Design Specifications. Concept generation, selection and evaluation are done in this
chapter. At the end of the chapter a final design concept is proposed for further
development.
Chapter 4 focuses on DFMA analysis of proposed design concept. Starting
with preparing the assembly drawing and explode drawing, the DFMA analysis is
done using Boothroyd-Dewhurst Methodology. This chapter ends with DFM analysis
of main part of the experimental apparatus.
Material preparation and fabrication process of the experiment apparatus is
included in Chapter 5. The fabrication processes are showed in sequence using series
of photograph. This chapter ends with complete apparatus that ready to the tested.
Chapter 6 deals with development of operating procedure of the apparatus
and apparatus testing. The procedure is prepared step-by-step and there are
photographs included at every steps performed. To avoid any accident, a safety
instruction is given and potential hazards are identified with safety countermeasure.
The chapter ends with an analysis of 1st Laws of Thermodynamics using data during
testing.
A discussion of overall project is done in Chapter 7. Included in the
discussion are product development processes, DFMA application as well as the 1st
Laws of Thermodynamics applied in this project. Overall results from the project are
also been discussed to evaluate the performance of developed apparatus.
7
The final chapter gives an overall conclusion about undertaken project. The
project achievement is summarized and concluded by referring to the end results
gained during completing the project. This chapter ends with recommendation for
future work that could be done for further improvement of the apparatus.
1.7 Summary
The project to design and development a portable experimental apparatus that
demonstrate the First law of Thermodynamics is carried out in two consecutive
semesters. The aim of the apparatus is to integrate between thermodynamics theory
and application. Boothroyd-Dewhurst DFMA Methodology had been applied in
design stage in order to minimize product components as well as to simplify the
design for ease of assembly and manufacture. To systematic organize design and
development tasks; a project objective, scopes and methodology are prepared to
ensure the project started in the right direction until the end.