CASE STUDY AT PT XYZ By Nicky - SGU Repository

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By

Nicky Widjaja 11407002

BACHELOR’S DEGREE in

INDUSTRIAL ENGINEERING

FACULTY OF ENGINEERING AND INFORMATON TECHNOLOGY

SWISS GERMAN UNIVERSITY The Prominence Tower

Jalan Jalur Sutera Barat No. 15, Alam Sutera Tangerang, Banten 15143 - Indonesia

August 2018

Revision after Thesis Defense on July 20^th, 2018

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Nicky Widjaja STATEMENT BY THE AUTHOR

I hereby declare that this submission is my own work and to the best of my knowledge, it contains no material previously published or written by another person, nor material which to a substantial extent has been accepted for the award of any other degree or diploma at any educational institution, except where due acknowledgement is made in the thesis.

Nicky Widjaja

_____________________________________________

Student Date

Approved by:

Dr. Tanika Dewi Sofianti, S.T., M.T.

_____________________________________________

Thesis Advisor Date

Anton Royanto Ahmad, S.T., M.Sc.

_____________________________________________

Thesis Co-Advisor Date

Dr. Irvan S. Kartawiria, S.T., M.Sc.

_____________________________________________

Dean Date

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Nicky Widjaja ABSTRACT

QUALITY ASSURANCE ANALYSIS OF BREAD PRODUCTION BY USING STATISTICAL QUALITY CONTROL (SQC) METHOD: CASE STUDY AT PT

XYZ

By

Nicky Widjaja

Dr. Tanika Dewi Sofianti, S.T., M.T., Advisor Anton Royanto Ahmad, S.T., M.Sc., Co-Advisor

SWISS GERMAN UNIVERSITY

This case based on the case study in PT XYZ, which is addressed to analysis of bread production by using Statistical Quality Control (SQC) method. The SQC method means collecting statistical data and analyzing by using seven basic tools of quality, such as cause-and-effect diagram, scatter diagram, pareto chart, and histogram. After that, it will be seen that cause of the problems. Then, the improvement is by revising Standard Operating Procedures (SOPs) on several division and area, and to adding check sheets method to record the data, which check sheets never been used by PT XYZ.

Keywords: Statistical Quality Control, SQC, seven basic tools of quality, Standard Operating Procedure, SOP, check sheet

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Nicky Widjaja

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Nicky Widjaja DEDICATION

I dedicate this thesis to me, myself, and I.

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Nicky Widjaja ACKNOWLEDGEMENTS

First of all, the author would like to express my biggest gratitude to my advisor, Dr.

Tanika Dewi Sofianti, S.T., M.T. and my co-advisor, Anton Royanto Ahmad, S.T., M.Sc. The author owes the deepest gratitude to my advisor and co-advisor that is always be there for the author and relentlessly keeps helping, guiding, motivating, and mentoring from the start until the completion of this thesis project.

The author also would like to thank PT XYZ for having me during this thesis work.

To all the head division, supervisors, and staffs within the company that providing every data and information needed for the completion of this project.

Special thanks to my dad, Santo Mulyadi Widjaja and Nany Moiras for praying for me, as always. And also, to Glenda Fransisca, the best support system ever.

Thanks to my friends: Iwan Tjoa, Gilbert Hermanto, Nikolas Rahardian, Daniel Surya, Adiva Nindito, Calvin Latu, Bob Edbert, and so on (The author can’t write it one-by-one, sorry).

Thanks to my gaming friends: Rihan Musthafa, Leonardo Aaron, and Andre Darmawan.

Last but not least, the same gratitude is given to fellow batch 2014 Swiss German University colleagues, all the Industrial Engineering batch 2014. Thank you for everything, see you on the top guys!

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Nicky Widjaja TABLE OF CONTENTS

Page

STATEMENT BY THE AUTHOR ... 2

ABSTRACT ... 3

DEDICATION ... 5

ACKNOWLEDGEMENTS ... 6

TABLE OF CONTENTS ... 7

LIST OF FIGURES ... 10

LIST OF TABLES ... 12

CHAPTER 1 - INTRODUCTION ... 14

1.1. Background ... 14

1.2. Research Problems ... 18

1.3. Research Objectives ... 18

1.4. Significance of Study ... 19

1.5. Thesis Structure ... 19

CHAPTER 2 - LITERATURE REVIEW ... 21

2.1. Quality ... 21

2.2. Quality Management ... 22

2.2.1. Quality Management Principles ... 23

2.2.2. Quality Planning ... 25

2.2.3. Quality Assurance ... 25

2.2.4. Quality Control ... 26

2.2.5. Quality Improvement ... 27

2.3. Total Quality Management (TQM) ... 28

2.4. Statistical Quality Control (SQC) ... 29

2.5. Seven Basic Tools of Quality ... 30

2.5.1. Cause-and-effect Diagram ... 31

2.5.3. Pareto Chart ... 32

2.6. Standard Operating Procedures (SOP) ... 33

CHAPTER 3 - RESEARCH METHODS ... 34

3.1. Research Methodology ... 34

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Nicky Widjaja

3.1.3. Analyzing and Defining the Causes of the Problems ... 36

3.1.4. Improvement Processes ... 36

3.1.5. Controlling the Improved Processes ... 36

CHAPTER 4 - RESULTS AND DISCUSSIONS ... 37

4.1. Company Profile ... 37

4.1.1. Operational Hours ... 37

4.1.2. Categories of Varieties of Products ... 38

4.2. Defining the Problems ... 41

4.3. Measuring Initial Condition Problems ... 41

4.3.1. Production Data ... 41

4.3.2. Defect Products Data ... 42

4.3.3. Existing SOP ... 47

4.3.3.1. SOP of Production ... 47

4.3.3.1.1. Bread Production SOP ... 48

4.3.3.1.2. Layered Cake Production SOP... 54

4.3.3.1.3. Cookies and Nastar Production SOP... 59

4.3.3.1.4. Mantou and Pao Production SOP ... 64

4.3.3.1.5. Pastry and Cake Production SOP ... 68

4.3.3.2. SOP of Purchasing ... 72

4.3.3.3. SOP of Recruitment ... 72

4.3.3.4. SOP of CCTV System Control ... 72

4.3.3.5. SOP of Visitors ... 73

4.3.3.6. SOP of Sales and Orders ... 73

4.4. Analyzing and Defining the Causes of the Problems ... 73

4.4.2. Types and Causes of Defect Products ... 76

4.4.3. Scatter Diagram ... 78

4.4.3.1. Scatter Diagram with Type of Defects: Moldy ... 78

4.4.3.2. Scatter Diagram with Type of Defects: Crack ... 81

4.4.3.3. Scatter Diagram with Type of Defects: Burnt... 83

4.4.3.4. Scatter Diagram with Type of Defects: Sour Taste ... 86

4.4.3.5. Scatter Diagram with Type of Defects: Black Spots ... 88

4.4.4. Pareto Chart ... 91

4.4.5. Histogram ... 93

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4.4.6.2. SOP of Raw Material Storage ... 95

4.4.6.3. SOP of Raw Material Preparation ... 96

4.4.6.4. SOP of Personal Hygiene ... 96

4.4.6.5. SOP of Hand-washing ... 97

4.4.6.6. SOP of Maintenance of Tools and Equipment Cleanliness ... 97

4.4.7. Controlling the Improved Processes ... 98

4.4.7.1. Added Check Sheets ... 98

4.4.7.2. Check Sheet of Raw Material Receival ... 99

4.4.7.3. Check Sheet of Raw Material Storage ... 99

4.4.7.4. Check Sheet of Raw Material Preparation ... 99

4.4.7.5. Check Sheet of Maintenance of Tools and Equipment Cleanliness ... 99

4.4.7.6. Check Sheet of Cleanliness of Tools and Equipment ... 100

CHAPTER 5 - TESTING PHASE ... 101

5.1 Test Description ... 101

5.2 Test Execution ... 105

5.3 Test Results ... 105

5.4 Test Analysis ... 114

CHAPTER 6 - CONCLUSIONS AND RECCOMENDATIONS ... 115

6.1 Conclusions ... 115

6.2 Recommendations ... 115

GLOSSARY ... 117

REFERENCES ... 118

APPENDIX A – Existing SOP in PT XYZ (Initial Condition) ... 120

APPENDIX B – Improvement Processes by Improving SOP ... 130

APPENDIX C – Controlling the Improved Processes by Check Sheets ... 138

APPENDIX D – Test Results ... 145

CURRICULUM VITAE ... 152