Design A Mini Depanelize Jig to Separate PCBA's From Panel Into Single Pieces.

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UNIVERSITI TEKNIKAL MALAYSIA MELAKA

Design a Mini Depanelize Jig to Separate

PCBA’s

From Panel into Single Pieces.

This report submitted in accordance with requirement of the Universiti Teknikal Malaysia Melaka (UTeM) for the Bachelor Degree of Manufacturing Engineering

(Manufacturing Design) with Honours.

Mohd Zaidi bin Jakaria B050710183

Faculty of Manufacturing Engineering May 2010

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UTeM Library (Pind.1/2007)

UNIVERSITI TEKNIKAL MALAYSIA MELAKA

BORANG PENGESAHAN STATUS LAPORAN PROJEK SARJANA MUDA

TAJUK: Design a Mini Depanelize Jig to Separate PCBA from Panel into Single Pieces SESI PENGAJIAN: 2009/2010 Semester 2

Saya: Mohd Zaidi b. Jakaria

mengaku membenarkan Laporan PSM ini disimpan di Perpustakaan Universiti Teknikal Malaysia Melaka (UTeM) dengan syarat-syarat kegunaan seperti berikut: 1. Laporan PSM adalah hak milik Universiti Teknikal Malaysia Melaka dan punulis . 2. Perpustakaan Universiti Teknikal Malaysia Melaka dibenarkan membuat salinan

untuk tujuan pengajian sahaja.

3. Perpustakaan dibenarkan membuat salinan laporan PSM ini sebagai bahan pertukaran antara institusi pengajian tinggi.

4. **Sila tandakan (√)

SULIT TERHAD

√ TIDAK TERHAD

(Mengandungi maklumat yang berdarjah keselamatan atau kepentingan Malaysia yang termaktub di dalam AKTA RAHSIA RASMI 1972)

(Mengandungi maklumat TERHAD yang telah ditentukan oleh organisasi/badan di mana penyelidikan dijalankan)

(TANDATANGAN PENULIS) Alamat Tetap:

40, Kg. Air Kerla, Gual Ipoh, 17500 Tanah Merah,

Kelantan Tarikh: _______________________ Disahkan oleh: (TANDATANGAN PENYELIA) Cop Rasmi: Tarikh: _______________________ ** Jika laporan PSM ini SULIT atau TERHAD, sila lampirkan surat daripada pihak berkuasa/organisasi berkenaan dengan menyatakan sekali sebab dan tempoh tesis ini perlu dikelaskan sebagai

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DECLARATION

I hereby, declare this thesis entitle “Design a Mini Depanelize Jig to Separate the PCBA from Panel into Single Pieces” is the result of my own research except as sites

in the reference.

Signature :………..

Authors Name : Mohd Zaidi b. Jakaria

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APPROVAL

This thesis submitted to the Senate of Universiti Teknikal Malaysia Melaka (UTeM) and has been accepted as partial fulfillment of the requirement for the degree of Bachelor of Manufacturing Engineering (Manufacturing Design). The members of supervisory committee are as follow:

……….

Hanizam b. Hashim (Official Stamp & Date)

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ABSTRACT

In order to optimize the productivity in PCBA manufacturing process, PCB’s are

design in panel form and have to be separated into single pieces before testing. This project is based on industrial problems at Cubic Electronics Sdn. Bhd. to cut the

printed circuit board panel. The PCB’s are separated by V-groove at top and bottom from one end to another and needs to be cuts in order to use them. The current technique is by using punch and pizza cutters/circular rotating blade and manually done by operators using jig or depanelize machine respectively. From the observations made at the company, the technique takes longer cycle time and difficult to handle for large panels. Although there is an automatic PCB cutter available in the market, the machine is far too expensive compared to the current machine. This project will be focusing on designing and improving the current Depanelize Jig in Cubic Electronic Sdn. Bhd.

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ABSTRAK

Dalam meningkatkan proses pengeluaran PCBA, PCB direkabentuk dalam bentuk panel dan perlu diasingkan/dipotong kepada satu satu bahagian litar. Projek ini berdasarkan masalah industri di Cubic Electronic Sdn. Bhd. untuk memotong litar daripada panel. Litar litar PCB ini di asing oleh lurah/alur V di atas dan bawah dan

perlu dipotong untuk digunakan. Teknik biasa yang digunakan adalah ‘punch’ dan

‘pizza cutters/circular rotating blade’ dan dilakukan secara manual oleh pekerja

dengan menggunakan mesin pemotong PCB. Daripada pemerhatian yang dibuat di syarikat tersebut, teknik yang digunakan memerlukan masa yang lebih dan sukar untuk menangani panel yang besar. Walaupun dipasaran terdapat pemotong PCB yang automatic, tetapi ia terlalu mahal jika dibandingkan mesin yang ada sekarang. Projek ini akan memfokuskan tentang merekabentuk dan menambahbaikan mesin yang terdapat di syarikat Cubic Electronic Sdn. Bhd.

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DEDICATION

For my mother, father and all my family and do not forget also to my friend and lecturer who helps me to complete this project.

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ACKNOWLEDGEMENT

First and foremost, I would like to thanks my supervisor of this project, En. Hanizam Hashim. His guidance and advice inspired me greatly to work in this project. His willingness to motivate me contributed tremendously to my project. I also would like to thank him for showing me some example that related to the topic of my project. Besides, I would like to thank the authority of Universiti Teknikal Malaysia Melaka (UTeM) for providing me with a good environment and facilities to complete this project. Also, I would like to take this opportunity to thank to the Cubic Electronic Sdn. Bhd. which provides me valuable information as the guidance of my project. Finally, an honourable mention goes to our families and friends for their understandings and supports on us in completing this project. Without helps of the particular that mentioned above, we would face many difficulties while doing this project.

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TABLE OF CONTENT

Abstract i

Abstrak ii

Dedication iii

Acknowledgement iv

Table of Content v

List of Tables viii

List of Figures ix

List of Abbreviations xi

1. INTRODUCTION

1.1 Problem Background 1

1.2 Problem Statement 2

1.3 Project Objectives 3

1.4 Scope of Project 3

2. LITERATURE RIVIEW

2.1 Printed Circuit Board (PCB) 4

2.1 Panelization 5

2.2 V-Groove 6

2.3 Surface Mount Technology (SMT) 7

2.3.1 SMT Tool/Material 8

2.3.2 Screen Printing 9

2.3.3 Part Placement/Chip mounting 10

2.3.4 Reflow Soldering 11

2.3.5 PCBA Depanelization 13

2.1.5.1 Current PCBA Depanelizer in Cubic Electronic Sdn. Bhd. 15

2.1.6 Wave Soldering 16

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2.4.1 Timing 18

2.4.2 Rating 18

2.4.3 Elements 18

2.4.4 Normal time 18

2.4.5 Allowances 19

2.4.6 Standard time 19

2.5 Break Even 19

2.5.1 The Break-Even Chart 20

2.5.2 Fixed Costs 20

2.5.3 Variable Costs 21

2.6 Jig Component 21

3. METHODOLOGY

3.0 Introduction 23

3.1 Gantt chart 24

3.1.1 Gantt Chart Clarification 25

3.2 Process Flow Chart 26

3.3 Process Flow 27

3.3.1 Data and Information Gathering 27

3.3.2 Identify Mechanism 28

3.3.3 Part Design 29

3.3.4 Material 32

3.3.5 Design Analysis 33

3.3.6 Design Simulation 35

4. RESULT AND ANALYSIS

4.0 Introduction 37

4.1 3D Modeling 37

4.2 Solidwork SimulationXpress 41

4.2.1 Existing Design 41

4.2.2 New Design 1 44

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vii

4.2.4 Stress on Chip Analysis 50

4.3 Time Study 52

4.4 Cost Analysis 56

4.4.2 Existing Jig 56

4.4.2 New Design 58

5. DISCUSSION

5.0 Introductions 60

5.1 Solidwork Simulationxpress Analysis 60

5.2 Time Study Analysis 62

5.3 Cost Analysis 63

6. CONCLUSION 65

7. RECOMMENDATION

7.0 Introductions 67

7.1 Suggestion and recommendation 67

REFERENCES 69

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viii

LIST OF TABLE

Table 2.3.5: Depaneling Method 13

Table 2.3.5.1: Example of Circular Rotating Blade

(Current Cubic Electronic Method) 16

Table 3.3.1: PCB Panel Size 28

Table 3.3.4: FR-4 Halogen Free 33

Table 4.1: New Depanelize Jig Process 38

Table 4.2: Result on PCB Board Analysis 49

Table 4.3.1: Time Study for existing jig 52

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LIST OF FIGURES

Figure 2.1: Printed Circuit Board 4

Figure 2.2: 18” x 24” (46mm x 61mm) panel example 5

Figure 2.3: V- Groove 6

Figure 2.4: SMT Flow Process 7

Figure 2.5: Solder Paste 8

Figure 2.6: solder paste screen or pattern 8

Figure 2.7: Printed Circuit Board (PCB) 8

Figure 2.8: Stencil Printing 9

Figure 2.9: Printing Process Illustration 9

Figure 2.10: Surface Mount Technology (SMT) 10

Figure 2.11: CUBIC Electronic Chip/IC Mounting Machine 11 Figure 2.12: Reflow Oven Showing zones Creates the Profile 12 Figure 2.13: Temperature Profile for SMT Reflow Soldering 12

Figure 2.14: 3 Phase Diagram 13

Figure 2.15: Wave Soldering Process 17

Figure 2.11: Breakeven Chart 20

Figure 2.12: Jig and Fixture Standard Component 22

Figure 3.1: Gantt chart 24

Figure 3.2: Process Flow Chart 26

Figure 3.3: Surface Mount Technology (SMT) process 27

Figure 3.4: PCB Panel 28

Figure 3.5: Existing Jig 29

Figure 3.6: Solidwork toolbar 30

Figure 3.7: Some part design in 3D 30

Figure 3.8: Part Downloaded 31

Figure 3.9: Product after mating process 31

Figure 3.10: Material for Jig (solidwork library) 32

Figure 3.11: Material Selection 34

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Figure 3.13: Solidwork Meshing processs 35

Figure 4.1: Mini Depanelize Jig 38

Figure 4.1: Force and Restrain applied (existing jig) 41

Figure 4.2: Stress on PCB (existing jig) 42

Figure 4.3: Safety Factor on PCB (existing jig) 43

Figure 4.4: displacement on PCB (existing jig) 43

Figure 4.5: Force and Restrain applied (New design 1) 44

Figure 4.6: Stress on PCB (New design 1) 45

Figure 4.7: Safety Factor on PCB (New design 1) 45

Figure 4.8: Displacement on PCB (New design 1) 46

Figure 4.9: Force and Restrain applied (New design 2) 47

Figure 4.10: Stress on PCB (New design 2) 48

Figure 4.11: Safety factor on PCB (New design 2) 48

Figure 4.12: Displacement on PCB (New design 2) 49

Figure 4.13: Flex Crack 50

Figure 4.14: Stress on Chip (existing jig) 51

Figure 4.15: Stress on Chip (New Design 2) 51

Figure 4.16: PCB Panel Cutting Line 52

Figure 5.1: Comparison Maximum Stress 61

Figure 5.2: Safety Factor & Displacement for 3 Designs 62

Figure 5.3: Output 63

Figure 5.4: Cost per part ` 64

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LIST OF ABBREVIATIONS

PCB Printed Circuit Board SMT Surface Mount Technology ICT In Circuit Test

PCBA Printed Circuit Board Assembly CAD Computer Aided Design

SMD Surface Mount Device

IR Infrared

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CHAPTER 1 INTRODUCTION

1.1 Problem Background

Depanelization is one important process in high volume electronic assembly production i.e. PCBA printed circuit board assembly. In order to increase the output of printed circuit board (PCB) manufacturing and surface mount (SMT) lines,

(Surface-mount technology (SMT) is a method for constructing electronic circuits in

which the components, are mounted directly onto the surface of printed circuit

boards) PCB are often designed so that they consist of many smaller PCBs that will

be used in the final product. This PCB cluster is called panel or multi block. The

large panel is broken up or “depaneled” as a certain step in the process. The

depaneling process may happen right after SMT process, after in circuit test (ICT), after soldering of through hole element or even right before the final case-up of the assembly depending on the product or process.

There are few depaneling cutting techniques that have currently been used in industry nowadays. The techniques have been used are:

a) Hand break

b) V-cut / Pizza cutter (The use of a pizza cutter to avoid the dislodging of loose

toppings through the back-and-forth motion of the blade typical of a knife.)

c) Punch d) Router e) Saw

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1.2 Problem Statement

This project is based on industrial problems at Cubic Electronics Sdn. Bhd. to cut the printed circuit board. The PCB comes in a panel form contains from double up to 100 pieces of single PCB’s in one panel. The PCBs are separated by V-groove at top and bottom from one end to another and needs to be cuts in order to use them. The current technique is by using punch and pizza cutters and manually done by operators using jig or depanelize machine respectively. From the observations made at the company, the technique takes longer cycle time and difficult to handle for large panels. Although there is an automatic PCB cutter available in the market, the machine is far too expensive compared to the current machine. The current depaneling machines have their own advantages and disadvantages.

Advantages of current depaneling machine

1. Lower cost – low cost because lower money is invested to buy the machine Disadvantages of current depaneling machine

1. Low productivity – less of outputs with longer cycle time need to operate the machine manually.

2. Cause stress to the circuits within the PCB layers – the current machine is using 2 rotating blades. The blades are used to press the v-cut and force it to be separated. The other process is using punching jig to break the edge breakaway PCB. These stresses that been introduced have very high risk to the internal circuits and components joints and may lead to short and open conditions. In addition, the PCBA will fail functionally and worst have to be scrapped.

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1.3 Objectives

The objectives of this study are to design a new PCB cutter machine which: 1. Design a PCB Depanelizing Jig

2. To reduce stress to PCB and chip during cutting process to reduce the reject part.

3. Cost effective – in term of overall performance of the machine and process for examples, reduce reject and cycle time.

4. Easy to handle – The operator easily can handle the machine without specific skills.

5. Improve the Productivity – use method and part that can improve the productivity of the output.

1.4 Scope of Project

In this project, several tools and equipment will be used in order to fulfil the objectives that have been stated. The scopes of this project are as follows:

1. PCB panel used is standard panel 18”x 24” (457mm x 610mm).

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CHAPTER 2 LITERATURE RIVIEW

2.0 Printed Circuit Board (PCB)

In 1950’s electronic companies started using Printed Circuit Board (PCB) to reduce

cost and errors. A simple PCB contains an insulating substrate (the board) which made of phenolic (a material made from paper and resin), fibreglass or ceramic. Then a thin layer of copper printed/placed on the board in a particular pattern to connect all the components mounted to the board. (Al Williams, 2004)

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2.1 Panelization

Panelization is required for all SMT boards and smaller boards (whether through-hole or SMT) to increase processing efficiencies. There are some considerations

when deciding to panelize or not. From an assembler’s perspective, panels are

desirable and sometimes necessary to provide the tooling holes and PCB edge

clearance requirements. The PCB manufacturer’s material utilization and cost of an

electrical test fixture should also be considered, which the main priority is often. (Tommy Ewing, 2007. Sibex Electronic)

The following are some considerations for circuits intended for panelization.

1. If components overhang the edge of the PCB, adequate space between circuits to allow all components to be installed on the panelized PCBs is necessary. The layout may allow for component clearance on the adjacent PCB so that material usage is not sacrificed.

2. Panels can be either scored or routed or a combination of each depending on the

application. For routed PCB’s the breakaway tabs should be drilled for inside breakaway. Copper Trace or plane clearance at the location of the breakaway tabs

should be at least 0.10” from the PCB edge. For V-Score, see below guideline. 3. Component weight and panel size should be considered to reduce the possibility

of warpage and/or breakage. Panels that are wave soldered (i.e. Through Hole Components) will tend to sag in the center when subjected to preheat and reflow temperatures.

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2.2 V-Groove

Figure 2.3: V- Groove

Sanmina-SCI Corporation)

 Minimum / maximum panel thickness (T1): 0.020” / 0.080” (0.5mm/2mm).

 Maximum score distance: 25”.

 Standard web thickness tolerance: +/- 0.005” (0.1mm).  Preferred score angle: 30 +/- 2 degrees.

 The standard/maximum web thickness (T2 in “Scoring diagram” figure): 0.012”/0.020” (0.3mm/0.5mm).

 Traces should be ≥ 0.040” away from the score line center on all outer and inner layers.

 Score line width should be 1.15 times the depth.

 One score test coupon per score line should be included in the net list; these score coupons will be designed as opens No board-to-board spacing is required.

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2.3 Surface Mount Technology (SMT)

Surface mounts technology (SMT) which component leads are attached directly on the surface of the board. The component that suitable with this technology called surface mount device (SMD). (Clive Maxfield, 2002).

In surface mount technology, the traditional component lead through is replaced with solder paste to hold the component on the surface of the PCB. A solder paste

template is made that’s allowing the placement of the components at required area. Then all the required components is placed manually or usually automatically placed onto the solder paste. A baking process allows the solder paste liquefies and the components remain soldered to the PCB. (David A. Madsen 2001 Ed. 3)

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2.3.1 SMT Tool/Material

The main raw material for screen printing is solder paste and the tool used are solder paste screen or pattern, solder paste and PCB.

Figure 2.5: Solder Paste

Figure 2.6: solder paste screen or pattern

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2.3.2 Screen Printing

The most commonly used solder paste disposition is stencil printing although the other technology also is being use like dispensing, pin-transferring and roller coating. A stencil usually made from metal foil with a pattern similar to footprint of PCB where deposition of solder paste desired. The solder paste will be deposited onto the stencil and will be wiped with squeegee across the stencil. The stencil then will be detached from the surface of the PCB with solder paste on top of the corresponding pads. The printing process normally being used because of the higher speed, higher through-put, better patterns registration and better solder paste volume control. (Ning-Cheng Lee, 2002)

Figure 2.8: Stencil Printing

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CHAPTER 2

LITERATURE RIVIEW

2.0 Printed Circuit Board (PCB)

In 1950’s electronic companies started using Printed Circuit Board (PCB) to reduce

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5 2.1 Panelization