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MINISTRY OF EDUCATION AND TRAINING

<b>HO CHI MINH CITY UNIVERSITY OF TECHNOLOGY AND EDUCATION FACULTY FOR HIGH QUALITY TRAINING </b>

<b> CAPSTONE PROJECT INDUSTRIAL MANAGEMENT</b>

<b>QUALITY CONTROL AT BOSCH VIETNAM BY APPLYING CONTAMINATION MANAGEMENT CYCLE </b>

<b>IN SYSTEM-CIP PROJECT</b>

<b>LECTURER: NGUYEN KHAC HIEU, PHD STUDENT: NGUYEN LE DUY KHANG </b>

<small>S K L 0 1 2 3 8 6</small>

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<b>HO CHI MINH CITY UNIVERSITY OF TECHNOLOGY ANDEDUCATION</b>

<b>FACULTY FOR ECONOMICS</b>

HO CHI MINH CITY, AUG 2023

<b>QUALITY CONTROL AT BOSCH VIETNAM BY APPLYINGCONTAMINATION MANAGEMENT CYCLE IN SYSTEM-CIP PROJECT</b>

<b>Student: NGUYEN LE DUY KHANGStudent ID: 20124368</b>

<b>Major: INDUSTRIAL MANAGEMENTAdvisor: NGUYEN KHAC HIEU, PHD</b>

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First and foremost, I would like to thank my supervisor, Mr. Nguyen Khac Hieu,for his guidance, feedback, and encouragement during my internship. He has been agreat mentor and a role model for me. He has helped me to improve my professionalskills and knowledge.

I am also grateful to the Faculty of Economics at HCMC University ofTechnology and Education for providing me with the opportunity and resources topursue my internship at BOSCH. I appreciate the knowledge and skills that I haveacquired from the faculty members during my studies. They have prepared me well forthe challenges and opportunities in the real world.

I would also like to acknowledge the contribution of BOSCH, my internshipcompany, for allowing me to learn from their expertise and experience. I am especiallythankful to MSE1 and my Buddy for involving me in various projects that enhancedmy practical knowledge and skills. I appreciate their kindness, generosity, andcooperation.

Last but not least, I would like to express my heartfelt gratitude to my parentsand friends for their unconditional love, care, and encouragement. They have alwaysbeen there for me in times of joy and hardship. They have motivated me to overcomethe challenges and difficulties that I faced along the way. I dedicate this report to them.

<i>HCMC, 26/Aug/2023</i>

<b>Student’s nameNguyen Le Duy Khang</b>

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<b>LIST OF ABBREVIATION</b>

HcP Ho Chi Minh City Plant

PC Commercial Plant ManagementPT Technical Plant ManagementCMC Contamination Management CycleCIP Continuous Improvement Process

KPI Key Performance IndicatorSPC Statistical Process ControlFMEA Failure Mode Effect Analysis

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<b>LIST OF TABLES</b>

Table 3.1: Contamination Management Cycle elements ...32

Table 3.2: Acceptance standard at Washing process...35

Table 3.3: RASIC chart...41

Table 3.4: Contamination count form...44

Table 3.5: “C” code for material in contamination code table...44

Table 3.6: Contamination code table... 47

Table 3.7: Contamination count raw data...48

Table 3.8: “Known source” Contamination in plastic...50

Table 3.9: “Known source” Contamination in metal... 51

Table 3.10: “Known source” Contamination in paper... 51

Table 3.11: “Known source” Contamination in cloth fiber...52

Table 3.12: “Known source” Contamination in tape...52

Table 3.13: “Known source” Contamination in paint... 53

Table 3.14: “Known source” Contamination in rubber ...54

Table 3.15: “Known source” Contamination by human ...54

Table 4.1: Expert’s information... 59

Table 4.2: Nomarlised Pair-wise comparison matrix... 60

Table 4.3: Pair-wise comparison matrix... 60

Table 4.4: Criteria weights table... 60

Table 4.5: Comparison matrices and local priorities...61

Table 4.6: Local and global priorities... 61

Table 4.7: Open Point List of Point-CIP project... 69

Table 4.8: Process Confirmation of Point-CIP project...70

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<b>LIST OF FIGURES</b>

Figure 1.1: Factual information and statistics about Bosch in Vietnam in 2021...5

Figure 1.2: Bosch Vietnam’s logo... 5

Figure 1.3: Organizational Chart at Hcp...7

Figure 1.4: Organizational Chart at MSE1 Department...9

Figure 1.5: Pushbelt...10

Figure 1.6: Pushbelt process ... 11

Figure 1.7: Element nomenclature...12

Figure 1.8: Flow and processes of element...13

Figure 1.9: Some of Bosch Vietnam’s customer...14

Figure 2.1: Warranty claims and repair cost of two companies...18

Figure 2.2: Distribution of quality characteristics of two companies... 18

Figure 2.3: Relationship of quality system, quality assurance and quality control... 20

Figure 2.4: Example of a check sheet... 21

Figure 2.5: Pareto principle...23

Figure 2.6: Histogram of claims on wet cement bags... 25

Figure 2.7: Different components of a control charts...27

Figure 2.8: Score about production levels by employees...28

Figure 2.9: Examples of scatter diagram ... 28

Figure 2.10: Stratification... 29

Figure 3.1: Pictures of Acceptance Standard at Washing process ... 36

Figure 3.2: Contamination case on product timeline from 2022 to present...36

Figure 3.3: Project plan... 38

Figure 3.4: Workflow of the contamination management cycle...40

Figure 3.5: Label for data collection...43

Figure 3.6: Areas applied contamination management cycle...45

Figure 3.7: Contamination count e-form... 46

Figure 3.8: Dashboard of contamination in ppm unit ...48

Figure 3.9: Dashboard of contamination in ppm unit ...49

Figure 4.1: KPI tracking of Point-CIP project ...63

Figure 4.2: Reaction plan on workplace of Point-CIP project... 65

Figure 4.3: General meeting form of Point-CIP project ...66

Figure 4.4: Reaction plan on floor/ other places of Point-CIP project...68

Figure 4.5: Closing meeting of Point-CIP project...71

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TABLE OF CONTENTS... vii

INTRODUCTION TO THE REPORT... 1

1. Rationale... 1

2. Aim of the study...2

3. Scope and object:... 2

4. Research methodology...2

5. Structure of the report...3

CHAPTER 1: INTRODUCTION TO BOSCH VIETNAM., LTD...4

1.1. Bosch Group... 4

1.2 Bosch Vietnam...5

<i>1.2.1. The process of formation and development... 5</i>

<i>1.2.2. Organizational Chart at HcP...7</i>

<i>1.2.3. Organizational Chart of MSE1 department...9</i>

1.3. Product and consumer market at Bosch Vietnam... 10

<i>1.3.1. Product... 10</i>

<i>1.3.2. Product at MSE1 (Element)... 12</i>

<i>1.3.3. Consumer market...14</i>

CHAPTER 2: LITERATURE REVIEW ... 16

2.1. Quality and quality improvement...16

2.2. Seven Quality Control Tools... 21

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3.1. Contamination Management Cycle Definition and Concept...32

3.2. Contamination measurement at Mixing, Washing and Supermarket... 39

<i>3.2.1. Process of collecting and analyzing contamination...39</i>

4.1 Solutions for eliminating contamination source...55

<i>4.1.1. Define cleaning frequency for human contamination, dust and repeatedcontamination with “unknown” source ... 55</i>

<i>4.1.2. Upgrade supermarket and forklift...56</i>

<i>4.1.3. Revise all work instruction at production area and create work instructions</i>...56

<i>4.1.4. Contact supplier... 57</i>

<i>4.1.5. Design removable cover for metal bin...58</i>

4.2. Solutions prioritization using AHP method... 58

4.3. Implementation Plan for the “Upgrade supermarket at forklift” solution ...624.4. Evaluate the solution’s effectiveness and control method by Point-CIP project63

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<b>INTRODUCTION TO THE REPORT1. Rationale</b>

The management of contamination in the production process is crucial fororganizations striving to increase the quality of their products. By effectivelyaddressing and mitigating contamination risks, companies can uphold customer value,drive innovation, and enhance overall product quality. This rationale is supported bythe following factors:

Customer Value and Innovation: In today's competitive market, customersatisfaction and loyalty are paramount. Customers expect products that meet high-quality standards and are free from any contaminants that could compromise theirperformance expectations. By proactively managing contamination in the productionprocess, organizations can consistently deliver products that are free fromcontaminants, ensuring they meet customers' stringent quality requirements., therebyenhancing customer value. Additionally, effective contamination management fostersinnovation by encouraging the exploration of new technologies, best practices, andcontinuous improvement in production processes.

By focusing on minimizing the risk related to product quality, the projectcontributes to the organization's objectives of customer satisfaction and operationalexcellence. It aligns with the company's vision by emphasizing the importance ofdelivering high-quality products and fostering innovation. Additionally, the projectaddresses the incident-related claim, prompting proactive measures to prevent futureoccurrences and safeguard the company's reputation. Through effective contaminationmanagement, the project significantly reduces the risk associated with compromisedproduct quality, supporting the organization's commitment to excellence and customervalue.

In conclusion, the author has chosen to delve into "Executing S-CIP project byapplying contamination management cycle at BOSCH Vietnam" due to its crucial rolein maintaining product quality and customer satisfaction. This topic offers valuableinsights into effective project execution strategies specifically tailored tocontamination management. By focusing on this aspect, the author aims to contribute

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to organizational success in minimizing contamination risks, ensuring superior productquality, and reinforcing customer trusts of market share

<b>2. Aim of the study</b>

Applying contamination management cycle at MSEx in Bosch Vietnam Co., Ltd.and reduce to zero contamination defect case case related to source of AOIs, Facetroom, Mixing-Washing-Supermarket per month.

<b>Space scope: HcP, Mixing process & Washing process & Supermarket line 7.</b>

<b>Time scope: from 01/04/2023 to 30/06/2023- Object:</b>

Applying contamination cycle at Mixing process, Washing process andsupermarket

<b>4. Research methodology</b>

The study utilized both qualitative and quantitative research approaches:

Qualitative research methods were employed to collect information regarding thechallenges affecting contamination in the MSE1 department. The author used focusgroup interviews to gain insights into issues and potential solutions from operators,engineers, and production experts. The insights gathered from these interviews helpedthe author comprehend the existing contamination situation along the production lineand gather recommendations for implementing solutions to eradicate thecontamination source.

Quantitative research methods were used to acquire data samples outlining theprerequisites for implementing CMC in production. The author employed statistical

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contaminations based on their materials and locations before proposing potentialsolutions.

<b>5. Structure of the report</b>

The structure of the thesis includes three main chapters and a conclusion section.Chapter 1: Introduction to Bosch Vietnam Co., Ltd

Chapter 2: Contamination Management Cycle definition and contaminationstatus at MSE1

Chapter 3: Solutions and control for contamination and evaluationConclusion

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<b>CHAPTER 1: INTRODUCTION TO BOSCH VIETNAM., LTD1.1. Bosch Group</b>

Bosch Group, a global powerhouse in engineering and technology, hasestablished itself as a prominent leader in various industries worldwide. With a historyspanning over a century, the company epitomizes innovation, precision, and reliability.Throughout its existence, Bosch has consistently pushed boundaries, reshapingindustries, and transforming lives through groundbreaking advancements.

Founded by Robert Bosch in Stuttgart, Germany in 1886, Bosch Groupcommenced its journey as a small workshop for precision mechanics and electricalengineering. Over time, the company gradually expanded its expertise and productrange, evolving into a diversified corporation with a strong presence in automotivetechnology, industrial technology, consumer goods, and energy and buildingtechnology.

Today, Bosch Group boasts a global footprint, operating in over 60 countriesand employing hundreds of thousands of dedicated professionals. Its commitment toexcellence is reflected in its diverse portfolio of products and services that cater to theneeds of individuals, businesses, and society as a whole. From automotive componentslike fuel injection systems and sensors to power tools, household appliances, andcutting-edge industrial solutions, Bosch's offerings span across diverse domains.

One of the key factors that sets Bosch Group apart is its unwavering focus onquality. The company's dedication to precision and craftsmanship has earned it anunparalleled reputation for reliability and durability. This commitment is deeplyingrained in Bosch's culture, influencing every aspect of their operations, fromresearch and development to manufacturing and customer service.

Furthermore, Bosch Group recognizes the importance of sustainability andcorporate social responsibility. Environmental protection, resource efficiency, andethical business practices are integral to its approach. The company actively pursuesinitiatives to reduce carbon emissions, optimize energy usage, and promote sustainablemanufacturing processes. Bosch's commitment to sustainability extends beyond itsown operations, as it collaborates with partners, customers, and stakeholders to drivepositive change in society and the environment.

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Bosch's success is underpinned by its relentless pursuit of innovation. Thecompany invests significantly in research and development, striving to anticipate andaddress evolving market needs. By embracing emerging technologies, such as artificialintelligence, Internet of Things (IoT), and connected solutions, Bosch remains at theforefront of digital transformation, driving advancements across industries.

<b>1.2 Bosch Vietnam</b>

<i><b>1.2.1. The process of formation and development</b></i>

<i>Figure 1.1: Factual information and statistics about Bosch in Vietnam in 2021Source: Company website</i>

Bosch Vietnam has embarked on a transformative journey of formation andgrowth, defining itself as a pioneering force in the Vietnamese market. Since itsestablishment in 1994, Bosch Vietnam has evolved from a humble representativeoffice into a flourishing full subsidiary, making substantial contributions to Vietnam'seconomic landscape.

<i>Source: Company websiteFigure 1.2: Bosch Vietnam’s logo</i>

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From the very beginning, Bosch Vietnam recognized the immense potential ofthe Vietnamese market and seized the opportunity to expand its operations. Throughstrategic investments and unwavering commitment, the company has diversified itsbusiness divisions, creating a diverse portfolio that spans automotive technology,consumer goods, industrial technology, energy and building technology, andhealthcare.

One of the key drivers behind Bosch Vietnam's success lies in its state-of-the-artmanufacturing facilities. Spread across different regions of Vietnam, these cutting-edge facilities not only cater to local demands but also serve as critical productionhubs for global distribution. By adhering to rigorous quality standards and leveragingadvanced technologies, Bosch Vietnam ensures the delivery of exceptional productsthat meet the ever-evolving needs of customers.

However, Bosch Vietnam's impact extends far beyond its manufacturing prowess.The company is deeply committed to fueling innovation through robust research anddevelopment initiatives. Collaborating closely with local partners, universities, andresearch institutions, Bosch Vietnam pioneers groundbreaking solutions tailoredspecifically to address the unique challenges faced by Vietnam. By harnessing thecollective expertise and knowledge of these collaborations, the company remains at theforefront of technological advancements, paving the way for a sustainable andprosperous future.

In addition to driving innovation, Bosch Vietnam is keenly aware of its corporatesocial responsibility. With a strong focus on education, skills training, environmentalstewardship, and community engagement, the company actively contributes to thebetterment of Vietnamese society. By empowering individuals and supporting localinitiatives, Bosch Vietnam strives to build a brighter future for generations to come.

As Bosch Vietnam continues to forge ahead, it stands tall as an emblem ofexcellence, ingenuity, and unwavering dedication. The company's formation anddevelopment underscore its commitment to Vietnam's progress, fostering economicgrowth, technological advancement, and social welfare. With a blend of globalexpertise and local insight, Bosch Vietnam remains poised to shape the nation's futureand leave an indelible mark on Vietnam's thriving industries.

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<i><b>1.2.2. Organizational Chart at HcP</b></i>

The Head of Commercial (HcP/PC) and Head of Technical (HcP/PT) at HcPhold the responsibility for making decisions, setting objectives, and providing theoverall direction for the company.

<i>Source: Company System Website</i>

<small></small>HcP/HSE (Health, Safety and Environment Department): oversees industrialsafety and provides safety instructions to workers prior to their entry into themanufacturing lines.

<small></small>HcP/MSE1: (Production Department): responsible for producing element.

<small></small>HcP/MSE2: (Production Department): responsible for producing loopset.

<small></small>HcP/MSE3: (Production Department): responsible for assembling to makepushbelt.

<small></small>HcP/TEF: (Technical Department): maintains machinery, performs repairswhen issues arise, manages documentation systems, oversees factory digitalization,and conducts research and development for product enhancement.

<small></small>C/AUP: accountable for planning production volume and turnover.

<i>Figure 1.3: Organizational Chart at Hcp</i>

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<small></small>PS/QMM (Quality Management and Methodology Department): sustainscustomer satisfaction through internal evaluations and IATF certification, whileensuring product quality through training in techniques such as SPC and FMEA.

<small></small>HcP/FCM (Facilities Management Department) supervises the upkeep offacilities and equipment to fulfill the requirements of the workforce.

<small></small>PS CT/ETC (Engineering Technology Center): provides assistance for existingproducts within Bosch Vietnam and Bosch's global transmission technology division,responsible for formulating testing strategies, executing them, and assessing the results.

<small></small>HcP/ICO (Information Coordination and Organization Department): handlesinformation security-related issues and facilitates the installation of software on thecompany's system.

<small></small>HcP/TGA (The Technical Training Center); provides technical training coursesto cultivate young, dynamic, and innovative internal talents.

<small></small>HcP/COM: responsible for commercial activities.

<small></small>HcP/LOG (Logistics Management Department): manages inventory levels,monitors the quantity of raw materials utilized for input and output, and tracks thequantity of items shipped to customers per order.

<small></small>HcP/CTG (Control Room): supervises the financial aspects and budget of theorganization.

<small></small>HcP/HRL (Human Resources Department): responsible for recruitment,training, compensation, and benefits.

<small></small>HcP/CMR (Security Department): supervises overall security within the factory,provides protocols and registration documentation for external partners visiting thefacility for filming or photography purposes, and assists with relevant documentation.

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<i><b>1.2.3. Organizational Chart of MSE1 department</b></i>

<i>Source: Company System Website</i>

The element production department includes:

MFO1(Operations): Supervisors and shift leader takes charge of the dailyproduction of components, meeting component demand, upholding productionstandards, managing workforce allocation, and executing production enhancements.

MSE1.2 (Line Engineering): Assumes the role of optimizing line performance,devising production plans, leading quality issue resolution efforts, overseeing line andproduct releases, and driving improvement initiatives (such as BPS and addressingbottleneck processes) in manufacturing.

MSE1.1 (Process Engineering): Is responsible for process improvement, qualityimprovement, troubleshooting, documentation, performing inspections and productreleases, and BPS activities in manufacturing. Including:

o MFE1.11: Fine blanking

o MFE1.12: Hardening, deburring, mixing & end of line washing.

<i>Figure 1.4: Organizational Chart at MSE1 Department</i>

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<b>1.3. Product and consumer market at Bosch Vietnam</b>

<i><b>1.3.1. Product</b></i>

<i>Figure 1.5: Pushbelt</i>

<i>Source: Company Website</i>

Pushbelt is a critical component of continuously variable transmissions (CVTs)that enables smooth and efficient power delivery. As an integral part of the CVTsystem, the pushbelt acts as a vital link between the driving pulleys responsible fortransmitting torque. By utilizing advanced materials and engineering expertise, Boschhas created pushbelts that can effectively handle high torque loads while maintainingoptimal performance.

One of the key advantages offered by Bosch's pushbelt technology is its ability toprovide stepless gear ratio changes. Unlike traditional automatic transmissions withfixed gear ratios, CVTs equipped with pushbelts allow for infinite variability withintheir operating range. This results in improved fuel efficiency, smoother acceleration,and enhanced driving comfort.

Bosch's pushbelts are engineered with precision and durability in mind. The beltsare designed to withstand high temperatures, friction, and wear, ensuring long-lastingperformance under challenging conditions. Advanced manufacturing techniques andquality control measures ensure consistent and reliable operation, reducingmaintenance requirements and enhancing overall vehicle reliability.

Furthermore, Bosch continuously invests in research and development to

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explores new materials, designs, and manufacturing methods to further optimizeperformance and efficiency. The pursuit of continuous improvement enables Bosch tostay at the forefront of pushbelt technology advancements, meeting the evolvingdemands of modern automotive applications.

The benefits of Bosch's pushbelt technology extend beyond passenger vehicles.This innovative solution finds application in a wide range of vehicles, includingcommercial vehicles, industrial machinery, and more. The versatility and adaptabilityof Bosch's pushbelts make them suitable for various power transmission requirementsacross different industries.

Moreover, Bosch's commitment to sustainability is evident in its pushbelttechnology. By optimizing power transfer efficiency and reducing energy losses,CVTs with pushbelts contribute to lower fuel consumption and reduced emissions.This aligns with the company's vision of sustainable mobility and its dedication tocreating environmentally friendly solutions.

In conclusion, Bosch's pushbelt technology has made significant strides inrevolutionizing transmission systems, enabling smooth and efficient power transfer inmodern vehicles. With a focus on performance, durability, and sustainability, Bosch'spushbelts have become integral components in continuously variable transmissions.Through ongoing research and development efforts, Bosch continues to improve thistechnology, setting new benchmarks for efficiency, reliability, and driving comfort inthe automotive industry.

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MSE3 department performs error checking for elements and loopsets andassembles to create a complete pushbelt product.

<i><b>1.3.2. Product at MSE1 (Element)</b></i>

<i>Source: MSE1 department of Bosch Vietnam Co., Ltd</i>

The Bosch Long Thanh factory in Dong Nai is the company's first beltmanufacturing facility in Vietnam and specializes in manufacturing continuouslyvariable transmission (CVT) belts. The plant in Vietnam has been manufacturing CVTbelts since 2008. In its initial production cycle, the factory produced 1.6 million goods.The manufacturer had distributed more than 25 million CVT belts as of March 2018.Three Bosch factories-one each in the Netherlands, Vietnam, and Mexico-produceCVT belts at the moment, with the Vietnam facility being the biggest and bringing inthe most money.

There are several types of elements. These elements vary in size andconfiguration, with a unique identification system denoting their specifications. Forinstance, an element labeled as "24-9" signifies that it possesses a horizontal length of24 millimeters and is equipped with nine loopsets that come together during assemblyto make a good pushbelt.

<i>Figure 1.7: Element nomenclature</i>

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With each element type, there are two kinds of element: normal element andfilter element. Filter element is like normal element but smaller and thinner, so it isused to be assembled into loopset to make a good pushbelt if the space is not enoughfor normal element.

These are element types: 24-9; 24-9AVO; 28-10; 30-10 and 30-12.

The full procedure of element includes: Fine-blanking  Hardening Deburring Body-grindingMixing Washing.

<i>Source: MSE1 department of Bosch Vietnam Co., Ltd</i>

Toolshop: This is a cabin used for storing and maintaining molds for the blanking process. It's where molds are maintained after use, reshaped, and othercomponents are worked on.

fine-Decoiling: Raw materials arrive in the form of a coil. Operators in charge ofthis step unwind the coil and feed it into the fine-blanking machine to create theproduct.

Fine-blanking: This process involves punching and cutting the coil to create theproduct using molds. Depending on the product type, a suitable mold is used. Theprocess follows the sequence of clamping, forming, cutting, and unloading.

Hardening: This is a heat treatment process aimed at increasing the hardness ofthe element.

<i>Figure 1.8: Flow and processes of element</i>

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Deburring: A grinding process that removes burrs, polishes the element, andcleans any dirt left from the fine-blanking process. Edges of the element are alsoground using stones, water, and chemicals.

Body grinding (only for specific products as required by Honda): This stepinvolves grinding to remove burrs from the flank part of the element.

Storage and Mixing: After grinding, elements are stored and later used in themixing process. Mixing aims to achieve a perfect blend of elements since, after fine-blanking, no two elements are exactly alike.

Washing: All elements are washed and then moved to a supermarket area toawait pickup requests from the assembly department.

<i><b>1.3.3. Consumer market</b></i>

<i>Source: Company website</i>

Bosch Vietnam excels in a pull system, offering make-to-order products to Asianmarkets. They serve notable industrial automobile customers like Hyundai, Honda,and Jatco. The factory focuses on producing the exclusive CVT (ContinuouslyVariable Transmission) Pushbelt, fulfilling orders from major clients such as Jatco,Honda, and Hyundai. With over 5000 employees, they achieve an impressive dailyproduction average of 1,700-2,000 belts per line, valued between $100 and $140 in the

<i>Figure 1.9: Some of Bosch Vietnam’s customer</i>

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market. Bosch Vietnam is a leading player in the thriving Asian industrial automobilesector.

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<b>CHAPTER 2: LITERATURE REVIEW2.1. Quality and quality improvement</b>

Quality has emerged as a pivotal factor influencing consumer choices when itcomes to selecting from a range of competing products and services. This trend isubiquitous and applies whether the consumer is an individual, a corporate entity, aretail outlet, a banking or financial institution, or even a military defense program. Assuch, comprehension and enhancement of quality are crucial elements that contributeto business prosperity, expansion, and heightened competitiveness. There is asignificant return on investment that can be derived from enhanced quality and thesuccessful integration of quality as a fundamental component of the overall businessstrategy. In this section, the author will provide practical definitions of quality andquality improvement. The author will initiate the discussion with a brief overview ofthe various dimensions of quality and some fundamental terminology.

According to Garvin (1987), quality is defined in eight dimension or components:<b>Performance: Customers typically evaluate a product based on its ability to</b>

perform specific functions and the efficiency with which it does so. For instance, onemight assess PC spreadsheet software packages based on the data manipulationoperations they can perform and their execution speed.

<b>Reliability: This pertains to the frequency of product failure. Complex</b>

products like appliances, automobiles, or airplanes are likely to require some repairover their lifespan. If a product requires frequent repairs, it is deemed unreliable. Thereliability dimension significantly impacts customer perception of quality in manyindustries.

<b>Durability: This refers to the effective service life of the product. Customers</b>

naturally prefer products that function satisfactorily over an extended period. Thisdimension is particularly important in industries like automobile and major appliances.

<b>Serviceability: This dimension considers how easily a product can be repaired.</b>

In many industries, customer perception of quality is directly influenced by the speedand cost-effectiveness of repairs or routine maintenance.

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<b>Aesthetics: This relates to the visual appeal of the product, often considering</b>

factors like style, color, shape, packaging options, tactile characteristics, and othersensory features.

<b>Features: Customers often associate high-quality products with added features</b>

- those that go beyond the basic performance offered by competitors.

<b>Perceived Quality: In many cases, customers rely on a company’s past</b>

reputation regarding the quality of its products. This reputation is influenced by highlyvisible product failures or recalls and by how customers are treated when they report aquality-related issue.

<b>Conformance to Standards: A high-quality product is often seen as one that</b>

precisely meets the requirements placed on it. For example, how well does a car hoodfit? Is it perfectly flush with the fender height, and is the gap exactly the same on allsides? Parts that do not precisely meet the designer’s requirements can causesignificant quality issues when used as components of a more complex assembly.

“Quality mean fitness for use”, this definition was defined by Dr. Juran is atraditional one in quality fields. Quality can be viewed from two perspectives: qualitydesign and quality conformance. Quality design refers to the intentional variations inproduct features that cater to different customer needs. For instance, consider a servicelike law enforcement by government agencies. The quality design is reflected in therelevant acts and rules, whereas the quality conformance depends upon how well theseacts and rules are complied with by the enforcement agencies.

On the other hand, quality conformance is concerned with how well a productaligns with the design specifications. Factors influencing quality conformance includethe selection of manufacturing processes, workforce training and supervision, processcontrols, tests and inspection activities employed, adherence to these procedures, andworkforce motivation to achieve quality.

However, there has been a tendency to associate quality more with conformancethan with design. This could be attributed to the limited formal education mostdesigners and engineers receive in quality engineering methodology. Consequently,there is often an overemphasis on a "conformance-to-specifications" approach toquality, regardless of whether the product meets the customer's needs when produced

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to standards. This mindset also perpetuates the misconception that quality issues canbe addressed solely in manufacturing or that improving quality necessitates "gold-plating" the product.

Moreover, there is a modern definition of quality. “Quality is inverselyproportional to variability”, and this definition only suggests that as the variability inthe significant attributes of a product diminishes, the product’s quality improves.

<i>Source: Douglas C. Montgomery (2008)Figure 2.1: Warranty claims and repair cost of two companies</i>

<i>Figure 2.2: Distribution of quality characteristics of two companies</i>

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<i>Source: Douglas C. Montgomery (2008)</i>

For example, in the past an American automobile company conducted acomparative study between a transmission manufactured domestically and oneproduced by a Japanese supplier. The study was prompted by a significant differencein warranty claims and repair costs, with the Japanese-made transmission proving tobe much more cost-effective (as shown in Figure 2.1).

The company randomly selected transmissions from each plant, disassembledthem, and measured several key quality characteristics. The results, generallyrepresented in Figure 2.2, showed that while both distributions of critical dimensionswere centered at the target value, the distribution for the US-manufacturedtransmissions occupied about 75% of the specification width. This suggested that veryfew nonconforming units would be produced and that the plant was producing at aquality level deemed quite good within the company.

In contrast, the same critical characteristics for the Japanese-manufacturedtransmissions only occupied about 25% of the specification band. This resulted insignificantly less variability in the critical quality characteristics of the Japanese-builttransmissions compared to those built in the US.

This finding is crucial. As Jack Welch, former CEO of General Electric, noted,customers don't see the process's mean (the target in Figure 2.2), they only see thevariability around that target that have not been removed. This variability often has asignificant impact on customers.

The reasons behind this difference are clear: reduced variability leads to lowercosts and superior product quality (as Welch pointed out). The Japanese-builttransmissions shifted gears more smoothly, ran more quietly, and were generallyperceived by customers as superior to those built domestically. Fewer repairs andwarranty claims result in less rework and waste of time, effort, and money. Thus,quality is indeed inversely proportional to variability and can be preciselycommunicated in a language everyone understands—money.

How did the Japanese achieve this? The answer lies in their systematic andeffective use of the methods described in this book, leading us to define qualityimprovement.

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“Quality improvement is the reduction of variability in processes and products”.High variability in process performance often leads to waste, as illustrated by the costsassociated with the repairs shown in Figure 2.1. Consequently, quality improvementcan be effectively defined as the reduction of waste. This definition is particularlyapplicable in-service industries where measurable elements may be less abundantcompared to manufacturing contexts, such as the transmission critical dimensionsdepicted in Figure 2.2. In these service industries, a quality issue might manifest as anerror or mistake, the rectification of which incurs additional effort and expense. Byenhancing the service process, this unnecessary expenditure of resources can becircumvented.

<i>Source: American Society for Quality</i>

According to the American Society for Quality, quality assurance and qualitycontrol are two aspect of quality management. Quality Assurance (QA) activities andresponsibilities typically encompass nearly all aspects of the quality system in somemanner, while Quality Control (QC) is considered a subset of these QA activities. It'salso worth noting that certain elements within the quality system may not be explicitlyaddressed by QA/QC activities and responsibilities, but may still involve aspects ofQA and QC. The definitions provided by ISO 9000:2015, titled "Quality management

<i>Figure 2.3: Relationship of quality system, quality assurance and qualitycontrol</i>

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systems - Fundamentals and Vocabulary," further elucidate this, as depicted in Figure2.3.

Quality Assurance (QA) can be defined as a component of quality managementthat is focused on instilling confidence that quality requirements will be met. Thisassurance serves a dual purpose - it provides internal assurance to management andexternal assurance to customers, government agencies, regulators, certifiers, and thirdparties. Another way to define QA is as the planned and systematic activitiesimplemented within the quality system that can be demonstrated to provide confidencethat a product or service will fulfill requirements for quality.

Quality Control (QC) can be defined as a component of quality management thatis focused on fulfilling quality requirements. While Quality Assurance (QA) pertainsto the manner in which a process is executed or a product is manufactured, QualityControl pertains more to the inspection aspect of quality management. An alternativedefinition of QC is the operational techniques and activities that are employed to fulfillrequirements for quality.

<b>2.2. Seven Quality Control Tools</b>

<i><b>2.2.1. Check sheet</b></i>

<i>Source: Pavletić, D., Soković, M., & Paliska, G. (2008).</i>

A Check Sheet is a crucial instrument for efficient data gathering andexamination. It's a structured form designed to systematically accumulate necessarydata.

<i>Figure 2.4: Example of a check sheet</i>

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This tool is typically used to pinpoint the frequency and location of issues in aproduct or service. Essentially, it's an empty form that methodically collects andorganizes factual data right at the source.

The Check Sheet is tailored to the process under scrutiny. It can record bothvariable and attribute data. The data gathered can be either qualitative or quantitative.When the data is quantitative, it's often referred to as a tally sheet. This collected datacan then serve as input for other quality tools like histograms, bar graphs, and Paretocharts.

Research on check sheets has demonstrated their significant utility in datacollection and analysis, particularly in areas such as quality management andproduction management. Montgomery and Woodall’s study in 2008 highlighted thepopularity of check sheets as a data collection method in quality control. The studyfurther revealed that check sheets simplify and enhance the efficiency of datacollection and analysis compared to other techniques.

In another study conducted by Pham et al. in 2019, check sheets were employedto gather data for assessing the appropriateness of production processes and suggestingenhancements. This study underscored that check sheets are a straightforward anduser-friendly tool for data collection and analysis in production processes.

In summary, a Check Sheet is a fundamental tool in data collection and analysis,particularly in the realms of quality and production management. Its design allows forsystematic and organized data collection directly from the source. It accommodatesboth variable and attribute data, which can be either qualitative or quantitative. Thelatter is often referred to as a tally sheet. The data collected can subsequently beutilized in various quality tools such as histograms, bar graphs, and Pareto charts.Studies have underscored the efficiency, simplicity, and user-friendliness of checksheets in data collection and analysis, making them a popular choice in quality controland production processes.

<i><b>2.2.2. Pareto Principle</b></i>

The Pareto Principle, often referred to as the 80-20 rule, suggests that 80% ofoutcomes result from 20% of all causes. This principle is a valuable tool in problem-

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solving as it helps prioritize the most significant contributors to a problem. Byfocusing on these key areas, one can achieve substantial results with minimal effort.

According to Prabir Jana & Manoj Tiwari (2021), The Pareto Principle, alsoknown as the 80:20 rule, is attributed to its founder, Vilfredo Pareto. This principleposits that 80% of outcomes are influenced or determined by 20% of activities orfactors. For instance, 20% of product categories generate 80% of the total profit, or20% of machines incur 80% of maintenance expenses. Given its widespreadapplicability in various situations and conditions, this principle is extensively utilizedin numerous fields, including inventory management, finance, and project planningamong others.

<i>Source: D. R. Kiran (2017)Figure 2.5: Pareto principle</i>

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Similarly, D. R. Kiran in 2017 indicated that in the context of Total QualityManagement (TQM), the Pareto Principle suggests that 20% of the causes result in80% of the total machine downtime. Thus, directing efforts towards this critical 20%can resolve 80% of the issues.

<i><b>2.2.3. Cause and Effect Diagram (Fishbone Diagram)</b></i>

The Ishikawa Diagram, also known as the Cause and Effect or Fishbone Diagramdue to its resemblance to a fish skeleton, is a visual tool developed by Kaoru Ishikawafor quality control in product design and defect prevention. It graphically representsthe complex interplay of causes for a specific problem or event, making it applicableto any type of problem and adaptable to various circumstances. The diagramencourages system thinking through visual linkages, keeps discussions focused oncurrent issues, and involves the workforce in problem resolution. It's straightforward,easy to learn, and helps prioritize further analysis and corrective actions. Each causeon the diagram is a source of variation for the phenomenon under study, making it aneffective tool for identifying potential factors causing an overall effect.

The Ishikawa Diagram is beneficial for problem-solving across various industries.Specifically, in the manufacturing industry, the categories of the Fishbone Diagram,according to the Toyota Production System, are known as the 6Ms. However,Management (money power) and Maintenance have been added later, expanding it tothe 8Ms. It's important to note that this expansion is not globally recognized.

Machine: the equipment, tools and technology used in manufacturing processes.Method: Process or procedure followed to manufacture the product.

Material: Raw materials, consumables and information

Manpower: human resources (including their skills, training and experience)Measurement: metrics and standards used to evaluate the manufacturingprocesses

Milieu/mother nature (Environment): external factors that can impact themanufacturing process.

<i><b>2.2.4 Histogram</b></i>

According to David W. Scott (2010), he provides a historical perspective on the

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of a random sample and an estimate of the underlying probability density function(pdf). The data points are tabulated into a list of disjoint bins. He emphasizes thesignificance of the histogram's invention in the seventeenth century, marking thetransition to modern statistics. Before this, statistical data was presented in lists orsummaries by category, providing more of an inventory than any deep understanding.Scott uses the example of an analysis of causes of death in seventeenth-centuryEngland to illustrate this point. He also highlights the work of Graunt in 1662, whoanalyzed the age of death from the bills of mortality and made a table, marking thebeginning of survival analysis by mortality tables.

On the other hand, Behnam Neyestani focuses on the practical application ofhistograms in modern contexts. He describes histograms as a useful tool forvisualizing both attribute and variable data of a product or process. Neyestaniemphasizes that histograms assist users in showing the distribution of data and theamount of variation within a process. He also points out that histograms displaydifferent measures of central tendency such as mean, mode, and average.

<i>Source: G, Paliska & Pavletic, Dusko & Sokovic, Mirko. (2007)</i>

In conclusion, both authors agree on the fundamental purpose and function ofhistograms but approach their explanations from different perspectives - Scott from ahistorical viewpoint and Neyestani from a practical application standpoint.

<i>Figure 2.6: Histogram of claims on wet cement bags</i>

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<i><b>2.2.5. Control Chart</b></i>

The Control Chart, also known as the Shewhart Chart, plays a pivotal role instatistical quality control. The concept of statistical control and the control chart werefirst introduced by Shewhart to achieve a state of statistical stability. The primary useof Shewhart Control Charts is twofold and serves two distinct purposes:

Achieving Statistical Control: This involves collecting appropriate data andtesting them against trial control limits to determine if a process has reached a state ofstatistical control.

Maintaining Current Control: This involves testing data against control limitsthat are computed from a given standard to maintain the current control of a process.

These charts are instrumental in monitoring process quality and introducingnecessary adjustments, thereby ensuring efficient operation and high-quality output.

A Control Chart is typically composed of a center line, an upper control limit,and a lower control limit, as depicted in Figure 2.7. Occasionally, for the user'scomprehension, the chart may also display the upper and lower specification limits.

When it comes to defining control charts for variables, there are severalcommonly used types:

X-R Charts: These charts are used to monitor the mean and range of a processbased on samples taken from the process at given times (hourly, daily, etc.). The Xpart represents the average for each subgroup, while the R represents the range.

X-S Charts: Similar to X-R charts, but instead of the range, the standarddeviation is used for variability. It's more accurate than the X-R chart when dealingwith larger sample sizes.

Individual Moving Range (IMR) Charts: These charts are used when it'simpractical or impossible to collect rational subgroups of data from a process. They'reuseful for tracking single output measures where you can't form subgroups.

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Each type of chart is designed to monitor variation within different types of datapatterns. The choice of chart depends largely on the specific parameters of the processbeing monitored.

<i>Source: Udayshankar (2015)</i>

<i><b>2.2.6. Scatter Diagram</b></i>

A scatter diagram, also known as a scatter plot or scatter graph, is a graphicaltool used to analyze the relationship between two variables. It helps determine howclosely the two variables are related. In a scatter diagram, one variable is plotted on thehorizontal axis (often the independent variable), and the other is plotted on the verticalaxis (usually the dependent variable). The data points are plotted as dots on these axes.The pattern of these dots can reveal the nature of the relationship between the twovariables. For instance, if the dots follow a linear pattern, it indicates a strongcorrelation between the variables. If the dots are scattered all over with no discerniblepattern, it suggests there’s no correlation.

According to Lyonnet, P. (1991), he elucidates that a scatter diagram, whichplots one variable against another, provides a visual representation of their relationshipand can suggest the extent of their correlation. For instance, consider a table thatpresents the aptitude test scores of several employees alongside their respectiveproduction levels over a specific period. A scatter diagram can effectively illustrate therelationship between these two sets of data.

<i>Figure 2.7: Different components of a control charts</i>

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<i>Source: Lyonnet, P. (1991)</i>

<i>Source: M. U. Afzal & A. M. Shahzad (2018)</i>

In a 2018 research study by M. U. Afzal and A. M. Shahzad, the authorsemployed a scatter diagram to examine the correlation between employee motivationand job performance. The findings of the study revealed a positive correlation betweenthese two variables, indicating that an enhancement in motivation corresponded to animprovement in job performance.

<i>Figure 2.8: Score about production levels by employees</i>

<i>Figure 2.9: Examples of scatter diagram</i>

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<i><b>2.2.7. Stratification</b></i>

<i>Source: Vienphanmem.com</i>

Stratification, in the context of quality control, is a tool used for sorting data,objects, and people into separate and distinct categories or classifications. This processworks by breaking down a large population into smaller groups of similar nature,allowing patterns in the data to become more apparent.

According to Metzger et al. (2005), stratification is employed to produce astatistical stratification of the European environment. This is particularly useful forstratified random sampling of ecological resources, selecting sites for representativestudies across the continent, and providing strata for modelling exercises and reporting.

<b>2.3 PDCA</b>

The Plan-Do-Check-Act (PDCA) cycle, alternatively known as the Deming orShewhart cycle, is a methodology rooted in lean manufacturing. It was conceived inthe 1930s, a time when exclusive products were becoming less prevalent and a newfocus on quality management and competitiveness was emerging in the global market.

The original PDCA cycle was the brainchild of American statistician Walter A.Shewhart. However, it was William Edward Deming who developed this method inthe 1950s into what is now one of the most globally recognized and applied

<i>Figure 2.10: Stratification</i>

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