Kuwait University College of Engineering and Petroleum Department of Industrial Engineering IE 496: Industrial Engineering Design Fall 2008
Leader: Hamid Al-Yousufi Vice Leader: Alaa’ Aboelfotoh
Abrar Hajiya Aisha Al-Roomi Amal Al-Fouzan Basel Nijem Elaf Ashkanani Farah Al-Doussery Maryam Al-Qatami Moneera Al-Fayyad Moudi Al-Abassi Nouf Al-Fraih Shaikha Al-Dabbous Shaima'a Dehrab Sherifa Al-Fulaij Zahra'a Amir
Supervised by: Prof. Mehmet Savsar . Eng. Bedour Al-Saleh Page | 1
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Acknowledgements
As I look at this book, finally printed and looking professional, I cannot help but remember all the pain and misery that went into putting it all together. I would like to thank and congratulate all my team members for their excellent contributions to this project and a special thank you to Basel Nijem, who put up with my obsession of having everything as perfect as possible. His tireless work in formatting this report made it a reality. However, before writing this book became a remote reality, we had to navigate the many presentations and deadlines set by our supervisor. None of this would have been possible without the amazing dedication of our priceless vice leader, Ala’a Aboelfotoh. For all your hard work, and having to put up with my insanity throughout the semester, thank you. Gratitude is also due to the IMSE faculty at KU, who guided us when we were lost, and kept making ever harder demands for the quality of our work. The staff at the National Canned Food Production and Trading Company deserves the utmost appreciation. They provided us with the data we needed whenever they could, and were friendly and courteous to us during our visits. To the families and friends of each and every member, a heartfelt thank you. Their love and support (and teasing) kept us going when we were down. Finally, I will not use the cliché that we hope you get as much pleasure from reading this book as we got from writing it, because it was a nightmare to write. Hamid Al-Yousufi On behalf of myself and my group, I would like to thank our dear staff for their assistance in making this design project a successful and pleasant one. We are particularly grateful to the great management and staff at the National Canned Food Production and Trading Company for all their assistance in providing us with the material required, and taking time off their work to help us. The coordination of all teams and the preparation of this report would not have been successful without the endless efforts of our leader Hamid Al Yousufi. A special thanks goes to Basel Nijem for his assistance in the editing and formatting of this report. Finally, I would like to thank all members for their hard work and congratulate them on their success. None of this would have been possible without the support of our families and friends to whom we owe much. Alaa Aboelfotoh
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Table of Contents Introduction 1.1 Company Background ..................................................................................... 12 Products ............................................................................................................................14
1.2 General Problem Description .......................................................................... 15 Quality Control 2.1 Introduction ...................................................................................................... 18 Problem Description............................................................................................................19 Objectives ..........................................................................................................................20 Solution Approach ..............................................................................................................20
2.2 Analysis of the As-Is System .......................................................................... 21 The Can Making Line ...........................................................................................................21 The Can Filling Line .............................................................................................................27 Local Lab ............................................................................................................................33 Central Lab .........................................................................................................................35 The As-Is Raw Material Sampling Plans ..............................................................................39 Quality Control Documentation ........................................................................................57
2.4 New Quality Control Documentation .............................................................. 73 2.5 New Sampling Plans ........................................................................................ 79 2.6 Proposed Double Sampling Plans For Beans................................................ 88 2.7 Proposed New Single Sampling Plan for Tin Sheets .................................. 116 2.8 Proposed Double Sampling Plans For Tin Sheets ...................................... 123 2. 9 Conclusion ..................................................................................................... 151 Cost Analysis 3.1 Introduction .................................................................................................... 154 3.1.1 Problem Description.................................................................................................. 155 3.1.2 Objectives ................................................................................................................ 156
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3.1.3 Solution Approach .................................................................................................... 156
3.2 Analysis of As-Is System: ............................................................................. 157 3.2.1 System .................................................................................................................... 157 1. Suppliers .................................................................................................................. 158 2. Customers ................................................................................................................ 161 3. Missions and Goals of The National Canned Food Company ............................................ 161 4. Resources ................................................................................................................. 161 5. Output ...................................................................................................................... 163 6. Outcome................................................................................................................... 163 7. Performance Measures .............................................................................................. 163 8. Decisions The National Canned Food Company Should Consider .................................... 163 3.2.2 Productivity Indices ................................................................................................... 164 1. Direct Cost ................................................................................................................... 164 Direct Labor Costs ......................................................................................................... 165 Direct Material Cost ....................................................................................................... 166 Equipment Direct Cost ................................................................................................... 177 2. Indirect Costs ................................................................................................................ 183 3. Overheads .................................................................................................................... 185 Technical Overheads ...................................................................................................... 185 Company Overheads...................................................................................................... 186 Marketing Overheads .................................................................................................... 186 5. Variable Cost................................................................................................................. 188 6. Fixed Costs ................................................................................................................... 190 7. Total Cost ..................................................................................................................... 190 8. Total Revenue: .............................................................................................................. 191 9. Total Profit ................................................................................................................... 192 10. Productivity Analysis Results ......................................................................................... 195 11. Break Even Point ......................................................................................................... 195
4. New System ...................................................................................................... 198 A. Overfilling: ................................................................................................................... 198 B. Transportation Costs ..................................................................................................... 200
5. Conclusion ........................................................................................................ 212
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Production Line Analysis and System Maintenance 4.1 Introduction .................................................................................................... 216 Problem Statement ........................................................................................................... 218 Objectives ........................................................................................................................ 218 Solution Approach ............................................................................................................ 218
4.2 Part List ........................................................................................................... 219 4.3 Bill of Materials (BOM) ................................................................................... 220 4.4 Component Part Drawing .............................................................................. 221 4.5 Process Description....................................................................................... 223 4.6 Process Flow on the Factory Layout ............................................................ 226 4.7 Operation Process Chart ............................................................................... 227 4.8 Route sheets ................................................................................................... 229 4.9 Data Collection and Fitting ............................................................................ 232 4.10 Maintenance Types ...................................................................................... 234 Corrective Maintenance (CM)............................................................................................. 234 Preventive Maintenance (PM) ............................................................................................ 235
4.11 Maintenance Plan ......................................................................................... 236 Current Maintenance Plan ................................................................................................. 237 Proposed Maintenance Plans ............................................................................................. 239 Alternative 1 ................................................................................................................. 239 Alternative 2 ................................................................................................................. 241 Alternative 3: ................................................................................................................ 244
4.12 The Reliability of the Lines .......................................................................... 247 4.13 Results .......................................................................................................... 251 Can Making Line ............................................................................................................... 251
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Can Filling Line.................................................................................................................. 252
4.14 Availability of the Machines ........................................................................ 254 Inherent Availability (Ai): ................................................................................................ 254 Achieved Availability (Aa) ................................................................................................ 255 Operational Availability (Ao) ............................................................................................ 255
4.15 Spare Parts ................................................................................................... 257 4.16 System Simulation ....................................................................................... 260 Problem Formulation ........................................................................................................ 262 System entities.............................................................................................................. 262 Material handling system ............................................................................................... 263 Current Problems in the Layout....................................................................................... 264 Work Schedule .............................................................................................................. 264 Scrap Estimate .............................................................................................................. 265 Policies ......................................................................................................................... 265 Simplification Assumptions ............................................................................................. 266 Coding the Arena Model of the As-Is System ........................................................................ 267 Explanation of the As-is Model of the Can Making Line ...................................................... 268 Can Filling line .................................................................................................................. 269 Explanation of the As-is Model of the Can Filling Line ........................................................ 271 Verification and Validation ................................................................................................. 273 Can Making Line ............................................................................................................ 273
4.17 Analysis of Daily Production Runs and Improvement .............................. 281 Can Making Line ............................................................................................................ 281 Can Filling Line .............................................................................................................. 287
4.18 Summary of the Proposed Alternatives ..................................................... 296 4.18 Conclusion .................................................................................................... 297 Inventory Management and Production Planning 5.1 Introduction .................................................................................................... 300 Problem description ......................................................................................................... 301 Solution approach ............................................................................................................. 302
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Methodology.................................................................................................................... 302
5.2 Analysis .......................................................................................................... 302 1- Demand forecasting ...................................................................................................... 303 2- Holt’s method ........................................................................................................... 304 Five Year Forecasts............................................................................................................ 385 Economic Order Quantity (EOQ) for Production Planning ...................................................... 399 Economic Production Quantity (EPQ) for Production Planning ............................................... 405 Service Level .................................................................................................................... 412
5.3 Conclusion ...................................................................................................... 418 Supply Chain Management 6.1 Introduction .................................................................................................... 420 Warehouses' Locations .................................................................................................. 424 Distribution Network ....................................................................................................... 425 Current Average Demand and Costs .................................................................................... 428 Problem Statement ........................................................................................................... 429 Solution Approach ............................................................................................................ 430
6.2 Analysis and Studies ..................................................................................... 430 Study 1: Establishing a New Factory .............................................................................. 432 Study 2: Using New Trucks ............................................................................................ 437 Justifications for Study 1 and Study 2 ............................................................................. 442 Study 3: Increasing Capacity of Existing Factory ............................................................ 445 Study 4: Demand Increase ............................................................................................. 450
6.3 Conclusion ...................................................................................................... 455 Safety and Human Factors 7.1 Introduction .................................................................................................... 458 Problem Description.......................................................................................................... 459 Objectives ........................................................................................................................ 460 Solution Approach ............................................................................................................ 460
7.2 Safety and Human Factors ............................................................................ 461
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7.3 Hazard Categories .......................................................................................... 463 7.4 Worker interaction with machine and material ............................................ 465 7.5 Data Collection and Findings ........................................................................ 466 7.6 Quick-win Improvements ............................................................................... 473 7.7 Long-term Improvement ................................................................................ 474 7.6 Management Control ...................................................................................... 487 7.7 Conclusion ...................................................................................................... 491 Facilities Planning 8.1 Introduction .................................................................................................... 494 Problem Statment ............................................................................................................. 495 Objectives ........................................................................................................................ 496 Solution Approach ............................................................................................................ 496
8.2 Current Layout................................................................................................ 497 Departments ................................................................................................................... 497 Blue Print of Factory ....................................................................................................... 505 As-Is Layout ................................................................................................................... 506
8.3 Material Handling ........................................................................................... 512 8.4 Method 1: Relationship Diagramming (RDM) Method ................................. 520 8.5 Method 2: CRAFT ........................................................................................... 535 8.6 Comparison of Method 1 and Method 2: Massaged Layouts ..................... 538 8.7 Proposed Layout ............................................................................................ 545 8.8 Savings in Cost .............................................................................................. 546 8.9 Conclusion ...................................................................................................... 548 General Conclusion ............................................................................................. 550
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1. Introduction
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1.1 Company Background
The National Canned Food Production and Trading Co. was founded in 1985 as Kuwait’s only producer of canned and processed food, under the DANIAH brand name and other local private labels, with a capital of 2,000,000 KD. Today it employs over 100 people. It is a subsidiary of Mezzan Holding Co.
Figure 1.1: Mother company and subsidaries.
The company’s objectives are to produce high quality canned food with a minimum number of defects on time to achieve customer and employee satisfaction.
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Products The company produces three main products: 1. Aqua Gulf water. 2. Vinegar. 3. Canned Food (220g, 400g, 450g)
The Foul Medammes: Foul Medammes American Variety, Foul Medammes with chili, Broad Beans, and Peeled Foul with chili.
Chickpeas: Chickpeas, Giant Garbanzo, with and without chili sauce.
Hommus Tahineh: Hommus Tahineh and Hommus Tahineh with garlic.
Peas: Green Peas, Mixed Vegetables, and Peas & Carrots.
Mushroom: Whole Mushrooms, Mushroom Pieces and Stems.
Olives: Black and Green Olives.
Corn: Whole Kernel Sweet Corn as well as new products such as Baby Corn, and Corn Cream.
Sausages: Frankfurter Sausages, Cocktail Sausages and Beef Sausages.
Beans: Baked Beans in tomato sauce, Black Eye Beans, White Beans, Red Kidney Bean, Red Kidney Beans with chili sauce, Butter Beans.
Figure 1.2: Products offered.
In this study, the production of the 400g cans was focused on since it comprises the bulk of production. In addition, the company produces its own cans. The factory has a separate line for Vinegar with which it produces White, Brown and Apple Vinegar. The factory also trades in Premium Sauces, including Tomato Ketchup, Chili Sauce, Hot Sauce, Extra Hot sauce, and Tomato Paste. Page | 14
1.2 General Problem Description
After thoroughly examining the factory and its operations, numerous, diverse problems were identified. Table 1.1 provides a summary of the problems found. The problems were categorized into an area of study within the Industrial Engineering discipline and teams were formed to study and eradicate each of these problems. Table1 .1: Summary of the problems identified.
General Problem Description
•
Inadequate raw material sampling plans. • Poor quality documentation. • Overfilling of cans during production. •
Unsafe working conditions.
Area of Study
Names Hamid Al-Yousufi
Quality Control
Human Factors and Safety
Shaima’a Dehrab Abrar Hajiya Nouf AL Fraih
•
High overfilling and transportation costs.
Cost Analysis
Amal AL Fouzan Shaikha Al Dabbous Aisha Al-Roumi
• •
Elaf Ashkanani Frequent machine failure. Poor maintenance plans.
Simulation and Maintenance Moudi Al-Abassi Zahra’a Amir Farah Al-Douseri
•
Company cannot meet the demand on time. • No specialized inventory plans in place. • Lead time is relatively long for final product.
Production Planning and Inventory Control
Maryam Al-Qatami Moneera Al-Fayyad Sherifa Al-Fulaij
•
Company at risk of being unable to satisfy demand even with overtime production hours.
Alaa Aboelfotoh Supply Chain Basel Nijem Alaa Aboelfotoh
•
Machines are too crammed, pathways are obstructed, inventory spread throughout the factory and a lot of wasted space.
Facilities Planning
Basel Nijem Nouf Al Fraih
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2. Quality Control
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2.1 Introduction When dealing with the food industry, there are many quality targets that need to be met. These include such things as bacteria count, weight accuracy, etc. The adequacy of the quality control system in place to achieve these targets was considered, by studying each test separately and determining whether action is needed to ensure the targets are being met. If a test returned a lot of negative values, attention was focused on it, to try and eliminate its cause by conducting a root cause analysis. The products being produced were also assessed to determine whether they meet all these targets. Furthermore, the raw material sampling plans in place were evaluated by using such measures as the probability of acceptance, the average outgoing quality, and the average total inspection. If any of the plans were found to be inadequate, new, superior plans were developed.
Problem Description After studying the current system in depth, three distinct problems were identified. First of all, the cans are being consistently over filled. This is a source of waste that will cause the company to lose money unnecessarily. Secondly, the quality management system in place is inadequate as the documentation is very poor and thus requires an immediate overhaul. In addition, there seems to be lack of vigilance in applying quality control, and a disregard for its importance. This could be due to the fact that the company is not aware of the costs involved in poor quality. Last but not least, some of the raw materials sampling plans in place require some modifications in order for them to adequately discriminate between lots of suitable and those of unsuitable quality.
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Objectives
The quality control documentation system shall be studied and optimized.
It shall be ensured that all the products adhere to all the specifications required. If not, the problems causing a failure to meet these specifications shall be identified and corrected.
New Sampling plans shall be developed that strike a balance between their different properties, such as the probability of acceptance and the costs involved.
Solution Approach In order to rectify the problems discussed previously, and to achieve the objectives set out, a root cause analysis was carried out to eliminate the over filling problem, as well as to bring the cost of overfilling to the attention of the company to educate the company as to the importance of proper quality control,. Furthermore, new quality documentation was developed to maintain a high level of quality control in the future. Finally, statistically reliable raw material sampling plans were proposed.
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2.2 Analysis of the As-Is System The Can Making Line The company produces its own cans. In this section, the can making line processes, as well as the quality control procedures implemented for each, is discussed. 1. Move a sheet metal box from storage to working area. Note: Sheet metal boxes are stored nearby. 2. Open box manually. 3. Transport sheets to cutting machine manually. 4. Sheet is cut according to required size. 5. Ready sheets are transported to electrical welding machine manually. Note: Feed rate: 160 sheets per minute. 6. Can is electrically welded. Note: Copper used to strengthen current. 7. Welded can is transported to lacquering machine by conveyor belt. 8. Varnish is applied to welded section of the can. 9. Can is transported to the oven by belt. 10. Oven heats up glue to allow it to set properly. 11. Random inspection carried out on cans exiting the oven. 12. Can is transported to flanging machine. 13. Can is flanged at both ends. 14. Can is transported towards separator. 15. Distance between consecutive cans is set to a specific amount to complement the speed of the seaming machine. Page | 21
16. Can is transported to seaming machine. 17. Lids fed into seaming machine to coincide with the arrival of the can. Note: Lids are stored and fed manually into the seaming machine. Note: 123,760 lids per box. 18. Lid is attached to the can using double seaming process. Note: Cans arrive upside down to get sealed from below. 19. Can is transported to storage area. Note: Due to the design of the conveyor belt, cans are turned upright during the transportation to the storage area. Note: Since the speed throughout the line is constant, the throughput is 160 cans per minute
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Detailed description of the Can Making Line Cutting Process: Tin sheets are taken from a box similar to the one shown in figure 2.1 which contains 1200-1500 sheets, depending on the supplier, and manually moved to the cutting machine shown in figure 2.2. Each sheet is cut into 32 blanks as seen in figure 2.3, before they are manually arranged into piles on a table next to the welding machine shown in figure 2.4.
Quality: At the start of the production run, the cutting machine blades are checked by producing thirty two blanks (that are used to manufacture the 400g cans) and examining the edges to determine if they are smooth enough. If not, the blades are sharpened. This is a qualitative test.
Figure 2.3: Sheets cut into 32 blanks.
Figure 2.1: A box of tin sheets.
Figure 2.2: The cutting machine.
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Welding Process: As depicted in figure 2.4, the tin blanks are fed manually into the welding machine, where they are bent into a cylindrical shape. Electric currents are induced, and are then strengthened by the presence of thin wires of copper, to weld the two edges of the metal blank. The copper wires only help generate electricity and are not part of the can itself.
Quality: At the start of production, the first four cans are inspected by applying the Pull Test, in which tension is applied to both sides before the can is checked for any tearing. During full production, two cans are taken every two hours and are subjected to the same test.
Figure 2.4: Blanks being fed into welding machine.
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Lacquering Process: The welded cans are moved using a conveyor belt from the welding machine to the lacquering area shown in figure 2.5, where a varnish is applied to both the outside and inside of the can’s welded area.
Quality: The varnish is checked by applying sixty strokes of MEK (a solution similar to paint thinner) to it. No rusting should occur.
Figure 2.5: The Lacquering area.
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Seaming Process: After cans are flanged on both sides, the cans are separated an even distance and enter the seaming machine, where the bottom of the can is sealed using double seaming. As can be seen in figures 2.6 and 2.7, the lids are stored adjacent to the line. Double seaming is used to ensure that no microscopic bacteria can invade its contents.
Quality: After the seaming process, 8 cans are taken every hour, and the following tests are carried out:
4 cans are manually inspected. If more than 35% of the cover hook consists of wrinkles, the can is scrapped.
4 cans undergo the leak test, which is shown in figure 2.8, where the cans are submerged in water and pressurized at 1.5-2 bar. The tank is then inspected for the presence of bubbles, which would suggest that leakages are occurring.
Figure 2.6: Lids stored next to the seaming machine.
Figure 2.7: Lids coincide with the
Figure 2.8: The leak test.
arrival of the cans.
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The Can Filling Line During the can filling process, the following variables/attributes are checked:
Dry weight
Net weight
Brine temperature
Application of labels
Soaking Process: The first step in the can filling line is soaking the beans in water in one to five of the three ton tanks, depending on the demand, shown in figure 2.9. The beans are usually left to soak for eight to fourteen hours, depending on the variety. This is usually done during the night.
Quality: A 100g sample is taken to check that soaking is correctly carried out. The weight should double after soaking.
Figure 2.9: Soaking tank.
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Filling Process: Solid food goes through the reel washer, a hollow cylindrical pipe with showers to wash the food. Next, the food is dropped into a bucket elevator which takes it to the blancher. In the blancher, the food is boiled for about ten minutes to remove any gases or enzymes, and then goes through a de-stoning process in which foreign objects are removed. After de-stoning, the food is carried to a hopper, a funnel-like tank, through bucket elevators. This helps regulate the flow of the food to the next step. To guarantee good quality, a final manual inspection is done after the de-stoning process. One layer of the food passes through workers on a conveyor. The workers check for any defects, such as darkly colored or mashed pieces, or tiny pieces of wood. After this, the food is again taken to another hopper using bucket elevators. At this point, the can making line and the can filling lines meet. The empty cans are washed, filled with food in the solid filling machine shown in figure 2.12, and then filled with brine (salted water solution) by the liquid filling machine.
Quality: As shown in figures 2.10 and 2.12, cans are checked at the start of production and the filling machine is calibrated accordingly until the nominal value is met. Once the line is operating properly, 10 cans are checked every 30 minutes. If any errors occur, the machine is calibrated again.
Figure 2.10: Dry weight being checked.
Figure 2.12: The solid filling Figure 2.11: The dry weight meets the nominal value.
machine.
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Seaming Process: Figure 2.13 shows cans going through the seaming machine where the top is seamed using double seaming.
Quality: Before the seaming process, a built-in thermostat checks the temperature of the brine. The temperature should not fall below 75 ˚C. After the seaming process, 8 cans are taken every hour, and the following tests are carried out:
4 cans are manually inspected. If more than 35% of the cover hook consists of wrinkles, the can is scrapped.
4 cans undergo the leak test, where the cans are submerged in water and pressurized at 1.5-2 bar. The tank is then inspected for the presence of bubbles, which would suggest that leakages are occurring.
Figure 2.13: Cans going through the seaming machine.
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Coding Process: The production date and time are stamped onto the cans. Figure 2.5 shows some cans that have been stamped. The ink used cannot be erased.
Quality: Since faulty coding would be extremely expensive; before production, one can of each product to be produced during the day is coded to make sure that the codes are correctly applied.
Figure 2.14: Coded cans.
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Cooking Process: The cans are cooked for between 10 and 70 minutes depending on the type of product.
Quality: Following the cooking in the retort area shown in figures 2.15 and 2.16, 2 cans from each cycle are taken and are qualitatively checked for the following attributes:
Color
Taste
Texture
Appearance
Figure 2.15: The ovens in the retort area.
Figure 2.16: Monitors to control the cooking process.
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Labeling Process: Labels are applied to the cans depending on the product and the brand as shown in figures 2.17 and 2.18
Quality: All cans going through the labeling machine are inspected to ensure that the labels are correctly applied. If labels are incorrectly applied, they are cut off and the can is re-labeled.
Figure 2.17: Labels being inspected.
Figure 2.18: A stack of labels.
Finally, after labeling, eight cans are sent to the municipality for health related checks. A further four cans are retained as a sample to check against future complaints.
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Local Lab All the tests carried out in the local lab shall now be discussed. They are split into chemical and physical tests. Chemical Tests Acidity Test 10 ml of brine is measured using a measuring cylinder and is diluted by using 100 ml of distilled water. Then the mixture is deposited in a conical flask before three drops of Phenolphthalein is added. Finally, NOH soda drops are added until the mixture changes color to purple as shown in figure 3.0, indicating that it has become neutral.
Figure 2.19: The mixture turns purple when neutral.
PH Test The PH meter shown in figure 2.20 is inserted into a bottle containing the brine and its PH is indicated on the display. A PH of 7 indicates its neutral, below 7 is acidic and above 7 is basic.
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Brix Test A few drops of brine are deposited on the brix meter shown in figure 2.21, and is then examined visually as in figure 2.21 and 2.22, to determine how much solid precipitation of minerals is present.
Figure 2.21: The brix meter.
Figure 2.22: Using the brix
Figure 2.23: The display of the brix.
meeting to test the brix content.
Physical Tests Weight Checks The net and drained weights are measured as can be seen in figures 2.24, 2.25 and 2.26. The net weight should not be below 400g but should not exceed 430g.
Figure 2.25: Measuring the drained weight. Figure 2.24: Equipment for measuring the net and drained weights.
Figure 2.26: Measuring the net weight.
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Central Lab Receiving the Samples Samples are received in the central lab and stored in the area shown in figure 2.27. They are transported in the coolers shown in figure 2.28 to avoid defrosting during the tri. When the sample is to be tested, it is divided into parts and some of it is stored in a refrigerator for retesting in case there is a problem with the findings of the initial test. The refrigerator shown in figure 2.29 is used to store media to be used in the microbiology tests.
Figure 2.28: The coolers
Figure 2.27: The entrance
carrying the samples.
to the sample sotrage area.
Figure 2.29: Refrigerator storing the test media.
0
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Media Preparation As can be seen in figure 2.30, the media are bought in powder form and are stored until needed. Figure 2.31 shows the instructions on the container to help prepare the medium using some certain solutions, some of which are shown in figure 2.32. The medium is then heated before it is inserted in the machine in figure 3.33, called the autoclave. Finally, the medium is placed in a Petri-dish and stored until it is needed as shown in figure 2.34.
Figure 2.30: The powder
Figure 2.31: Instructions for
media stored.
preparing the media.
Figure 2.32: Liquid solutions used in
Figure 2.34: The petri dishes Figure 2.33: The autoclave
preparing the media.
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Microbiology Tests A 10g sample is diluted using 100ml of the buffer solution shown in figure 4.35, and it is then placed in the incubator shown in figure 4.36 for 2 hours at 37°C, after which it is poured in a sterilizing cup and placed in a sterilizer for between 15 and 20 minutes at 80°C, as shown in figure 2.37.
The tests in figure 2.38 count for:
Total Bacteria
Anaerobic
Salmonella
Yeast and Mold
All of them should be nil.
Figure 2.35: The buffer solution.
Figure 2.36: The incubator.
Figure 2.38: Tests counting for Figure 2.37: The sterilizer.
bacteria presence.
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Canned Food Once the sample is received (note: the number of cans in the sample varies according to the production scheduled for that day), one of the cans is taken as a fresh sample and immediately undergoes weight, PH, and brix tests. The rest of the sample is split into 2 groups of equal size. One is stored at 55°C, whilst the other is stored at 37°C as shown in figure 2.39, and kept for 5 days before they undergo the same tests as the fresh sample.
Figure 2.39: Samples kept at 55°C for 5 days.
Note: The central lab carries out all the tests in the local lab, in addition to the microbiology tests discussed.
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The As-Is Raw Material Sampling Plans The current sampling plans used to test the quality of the incoming raw materials are evaluated in this section. The probability of acceptance, the average outgoing quality and the average total inspection were calculated for each plan. Note that most raw materials do not undergo acceptance sampling since the municipality already checks all food materials coming into Kuwait and in the case of such materials as glue, the company has an excellent relationship with its suppliers and is therefore confident enough to accept lots without subjecting them to sampling. The raw materials that do undergo sampling are the beans, the standard lids, the easy open lids, and the tin sheets. For all raw materials, one sample is taken before the lot is sentenced. Therefore, they were modeled as single sampling plans using the following equations:
The terminology is as follows:
n: The sample size.
N: Lot size.
C: Number of defective units accepted in a sample.
Pa: The probability of acceptance. d: The number of defective units in the p: Lot percentage defective.
sample.
Lots consisting of 1% defective items are deemed acceptable. Therefore, the sampling plans must have a high Pa value at p = 0.01.
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Beans Sampling Plan N = 400 n = 20 c=0
Table 2.1: Summary of the beans sampling plan.
Beans p
Pa
AOQ
ATI
0.01
0.8179
0.78%
89
0.02
0.6676
1.27%
146
0.03
0.5438
1.55%
193
0.04
0.4420
1.68%
232
0.05
0.3585
1.70%
264
0.06
0.2901
1.65%
290
0.07
0.2342
1.56%
311
0.08
0.1887
1.43%
328
0.09
0.1516
1.30%
342
0.10
0.1216
1.15%
354
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Probablity of Acceptance for the As-Is Beans Sampling Plan 1.00 0.80
Pa
0.60 0.40 0.20 0.00 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.40: Probability of acceptance for the beans sampling plan.
Table 2.2: Probability of acceptance for different values of p for beans sampling plan.
p
Pa
0.01
0.8179
0.02
0.6676
0.03
0.5438
0.04
0.4420
0.05
0.3585
0.06
0.2901
0.07
0.2342
0.08
0.1887
0.09
0.1516
0.10
0.1216
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AOQ
AOQ for the As-Is Beans Sampling Plan 1.80% 1.60% 1.40% 1.20% 1.00% 0.80% 0.60% 0.40% 0.20% 0.00% 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.41: AOQ for the beans sampling plan.
Table 2.3: AOQ for different values of p for beans sampling plan.
p
AOQ
0.01
0.78%
0.02
1.27%
0.03
1.55%
0.04
1.68%
0.05
1.70%
0.06
1.65%
0.07
1.56%
0.08
1.43%
0.09
1.30%
0.10
1.15%
Page | 42
ATI for the As-Is Beans Sampling Plan 400 350 300
ATI
250 200 150 100 50 0 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.42: ATI for the beans sampling plan.
Table 2.4: ATI for different values of p for beans sampling plan.
p
ATI
0.01
89
0.02
146
0.03
193
0.04
232
0.05
264
0.06
290
0.07
311
0.08
328
0.09
342
0.10
354
Page | 43
As can be seen in figure 2.42 the probability of acceptance is low even at low values of p. At a p = 0.01, Pa is only 81.79%. A new sampling plan for this raw material is needed. Standard Lids Sampling Plan N = 4,000,000 n = 50 c=2 Table 2.5: Summary of the standard lids sampling plan.
Standard Lids p
Pa
AOQ
ATI
0.01
0.9862
0.99%
55,318
0.02
0.9216
1.84%
313,757
0.03
0.8108
2.43%
756,848
0.04
0.6767
2.71%
1,293,178
0.05
0.5405
2.70%
1,837,895
0.06
0.4162
2.50%
2,335,035
0.07
0.3108
2.18%
2,756,861
0.08
0.2260
1.81%
3,096,114
0.09
0.1605
1.44%
3,357,846
0.10
0.1117
1.12%
3,553,091
Page | 44
Probablity of Acceptance for the As-Is Standard Lids Sampling Plan 1.00 0.80
Pa
0.60 0.40 0.20 0.00 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.43: Probability of acceptance for the standard lids sampling plan.
Table 2.6: Probability of acceptance for different values of p for standard lids sampling plan.
p
Pa
0.01
0.9862
0.02
0.9216
0.03
0.8108
0.04
0.6767
0.05
0.5405
0.06
0.4162
0.07
0.3108
0.08
0.2260
0.09
0.1605
0.10
0.1117
Page | 45
AOQ for the As-Is Standard Lids Sampling Plan 3.00% 2.50%
AOQ
2.00% 1.50% 1.00% 0.50% 0.00% 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p
Figure 2.44 AOQ for the standard lids sampling plan. Table 2.7: AOQ for different values of p for standard lids sampling plan.
p
AOQ
0.01
0.99%
0.02
1.84%
0.03
2.43%
0.04
2.71%
0.05
2.70%
0.06
2.50%
0.07
2.18%
0.08
1.81%
0.09
1.44%
0.10
1.12%
Page | 46
ATI for the Standard Lids Sampling Plan 4,000,000 3,500,000 3,000,000
ATI
2,500,000 2,000,000 1,500,000 1,000,000 500,000 0 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p
Figure 2.45: ATI for the standard lids sampling plan.
Table 2.8: ATI for different values of p for standard lids sampling plan
p
ATI
0.01
55,318
0.02
313,757
0.03
756,848
0.04
1,293,178
0.05
1,837,895
0.06
2,335,035
0.07
2,756,861
0.08
3,096,114
0.09
3,357,846
0.10
3,553,091
Page | 47
Figure 2.45 shows that the probability of acceptance is as high as 98.6% at p = 0.01 and falls quickly as p increases. This is a very effective sampling plan.
Easy Open Lids Sampling Plan N = 1,400,000 n = 50 c=2 Table 2.9: Summary of the easy open lids sampling plan.
Easy Open Lids p
Pa
AOQ
ATI
0.01
0.9862
0.99%
19,946
0.02
0.9216
1.84%
112,982
0.03
0.8108
2.43%
272,491
0.04
0.6767
2.71%
465,566
0.05
0.5405
2.70%
661,659
0.06
0.4162
2.50%
840,626
0.07
0.3108
2.18%
992,480
0.08
0.2260
1.81%
1,114,608
0.09
0.1605
1.44%
1,208,830
0.10
0.1117
1.12%
1,279,116
Page | 48
Probablity of Acceptance for the As-Is Easy Open Lids Sampling Plan 1.00 0.80
Pa
0.60 0.40 0.20 0.00 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p
Figure 2.46: Probability of acceptance for the easy open lids sampling plan.
Table 2.10: Probability of acceptance for different values of p for easy open lids sampling plan.
p
Pa
0.01
0.9862
0.02
0.9216
0.03
0.8108
0.04
0.6767
0.05
0.5405
0.06
0.4162
0.07
0.3108
0.08
0.2260
0.09
0.1605
0.10
0.1117
Page | 49
AOQ for the As-Is Easy Open Lids Sampling Plan 3.00% 2.50%
AOQ
2.00% 1.50% 1.00% 0.50% 0.00% 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p
Figure 2.47: AOQ for the easy open lids sampling plan.
Table 2.11: AOQ for different values of p for easy open lids sampling plan.
p
AOQ
0.01
0.99%
0.02
1.84%
0.03
2.43%
0.04
2.71%
0.05
2.70%
0.06
2.50%
0.07
2.18%
0.08
1.81%
0.09
1.44%
0.10
1.12%
Page | 50
ATI for the Easy Open Lids Sampling Plan 1,400,000 1,200,000
ATI
1,000,000 800,000 600,000 400,000 200,000 0 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.48: ATI for the easy open lids sampling plan.
Table 2.12: ATI for different values of p for easy open lids sampling plan.
p
ATI
0.01
19,946
0.02
112,982
0.03
272,491
0.04
465,566
0.05
661,659
0.06
840,626
0.07
992,480
0.08
1,114,608
0.09
1,208,830
0.10
1,279,116
Page | 51
Figure 2.48 shows that the probability of acceptance is as high as 98.6% at p = 0.01 and falls quickly as p increases. This is a very effective sampling plan. Tins Sheets Sampling Plan N = 420,000 n = 10 c=0 Tin sheets p
Pa
AOQ
ATI
0.01
0.9044
0.90%
40,169
0.02
0.8171
1.63%
76,838
0.03
0.7374
2.21%
110,289
0.04
0.6648
2.95%
140,777
0.05
0.5987
2.99%
168,536
0.06
0.5386
2.69%
193,787
0.07
0.4850
2.42%
216,732
0.08
0.4344
2.17%
237,561
0.09
0.3894
1.95%
256,449
0.10
0.3487
1.74%
273,559
Table 2.13: Summary of the tin sheets sampling plan.
Page | 52
Probablity of Acceptance for the As-Is Tin Sheets Sampling Plan 1.0000 0.8000
Pa
0.6000 0.4000 0.2000 0.0000 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p
Figure 2.49: Probability of acceptance for the tin sheets sampling plan. Table 2.14: Probability of acceptance for different values of p for tin sheets sampling plan.
p
Pa
0.01
0.9044
0.02
0.8171
0.03
0.7374
0.04
0.6648
0.05
0.5987
0.06
0.5386
0.07
0.4850
0.08
0.4344
0.09
0.3894
0.10
0.3487
Page | 53
AOQ for the As-Is Tin Sheets Sampling Plan 3.50% 3.00%
AOQ
2.50% 2.00% 1.50% 1.00% 0.50% 0.00% 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.50: AOQ for the tin sheets sampling plan.
Table 2.15: AOQ for different values of p for tin sheets sampling plan.
p
AOQ
0.01
0.90%
0.02
1.63%
0.03
2.21%
0.04
2.95%
0.05
2.99%
0.06
2.69%
0.07
2.42%
0.08
2.17%
0.09
1.95%
0.10
1.74%
Page | 54
ATI for the As-Is Tin Sheets Sampling Plan 300,000 250,000
ATI
200,000 150,000 100,000 50,000 0 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.51: ATI for the tin sheets sampling plan.
Table 2.16: ATI for different values of p for tin sheets sampling plan.
p
ATI
0.01
40,169
0.02
76,838
0.03
110,289
0.04
140,777
0.05
168,536
0.06
193,787
0.07
216,732
0.08
237,561
0.09
256,449
0.10
273,559
Page | 55
As can be seen in figure 2.51, the probability of acceptance is low even at low values of p. At a p = 0.01, Pa is only around 90%. A new sampling plan for this raw material is needed. From studying the three different properties for each sampling plan, it was conclude that the plans for the beans and tin sheets need to be redesigned because the Pa curves are inadequate. The procedure followed in the design of the new plans is shown in sections 9 and 10 of the report.
Page | 56
Quality Control Documentation Having studied the quality control documentation in place, the finished product quality sheet shown in figure 2.52 was found to be particularly inadequate as it does not record individual data and wastes a lot of space on tests that always return a positive result. Thus, it was decided to come up with new designs based on statistical and economical considerations. The new quality sheets as well as the properties taken into consideration while designing them are discussed in detail in section 8. Figure 2.53 shows the brine quality sheet which does not show the standards that need to be met for each product. It was therefore recommended that a sheet with all the standards written be posted in a clearly visible location in the lab. Finally, after discussions about the central lab results with the quality personnel, it was noticed that the specifications are not realistic and need to be changed since many results for the brix and PH fall outside the limits even though they were of acceptable quality. It is therefore imperative that the specifications are reset in conjunction with the input of the quality engineers.
Page | 57
Figure 2.52: The as-is finished product quality sheet.
Page | 58
Figure 2,53: The As-Is brine quality sheet.
Page | 59
2.3 Pareto Analysis of Can Defects After studying quality control data for a whole month’s worth of production, there was a need to pinpoint the most common types of defects that occurred. A Pareto chart was used. The Pareto chart is one of the seven basic tools of quality control, which include the histogram, Pareto chart, check sheet, control chart, cause-and-effect diagram, flowchart, and scatter diagram. The Pareto chart is a special type of bar chart where the values being plotted are arranged in descending order. A Pareto chart was constructed for the different types of defects in the can filling process and determined which defects were to be studied in depth. As shown in figure 7.0, the main problems were the brine temperature and net weight.
Types of Defects 35 30 25 20 15 10 5 0 Brine Net Weight Temprature
Filling weight
Vegetable Oil
Seaming
Lacquering
Coding
Figure 2.54: Pareto chart for types defects.
Page | 60
Brine Temperature Problem Upon further inspection, it was found that there was only one incident where the temperature was below 70°C. After discussing this with the quality engineer, it was discovered that products with 70°C brine are acceptable. The target of a minimum temperature of 75°C is set to keep a safety buffer. Therefore, there was no need to waste resources studying a problem that did not exist.
Net Weight Problem A root cause analysis was conducted to pinpoint the source of the problem. Various quality tools, including the why-why diagram, fishbone diagram, and control charts were used in the analysis. Since production is sporadic, meaning a single product will not be produced continually but will be produced based on demand and thus can sometimes be produced on a monthly basis, for example, there were not enough data points to construct a control chart with a proper sub group size. Therefore, individual and moving range charts were constructed instead, to study the performance of the filling system. The products used for this analysis were the chick peas and green peas since they account for the bulk of production (almost 40%). Note that the nominal value for the 400g cans is set at 415g with a tolerance of ±15g.
Page | 61
Why-Why Diagram
Figure 2.55: Why-why diagram for the cause of overfilling.
Page | 62
Fish Bone Diagram
Figure 2.56: Fish bone diagram for the cause of overfilling.
Page | 63
Control Charts Individual and Moving Range Charts for the Net Weight of Chick Peas
Figure 2.57: Control chart for the net weight of chick peas.
Comments:
Points are randomly scattered.
The process average is too close to upper specification limit.
Points 12-17 indicate lack of vigilance in meeting the target as the weight keeps increasing.
70% of points within ± 1σ.
96.67% of points within ± 2σ.
The Process is under control.
Overfilling could be due to a problem in the dry filling. Therefore, we decided to study the filling weight as well.
Page | 64
Table 2.17: Net Weight data of Chick Peas for the month of October.
Net Weight of Chick Peas 430
430
424
426
426
430
430
428
432
430
434
428
430
430
432
430
430
430
425
426
430
428
426
424
430
428
432
430
430
Page | 65
Individual and Moving Range Charts for the Filling Weight of Chick Peas
Figure 2.58: Control chart for the filling weight of chick peas.
Comments:
The nominal value for the chick peas filling weight is 205 with a tolerance of ±5g.
The points are randomly scattered.
The process average is close to the upper specification limit.
The only out of control point corresponds to the nominal target!
Runs of points of equal value indicate ability to consistently produce cans at the same weight.
86.67% within ± 1σ.
Too many points lie outside the 2σ boundaries. The process variation must be lowered by being more proactive in changing the process average when deviations from the nominal target occur.
Page | 66
Table 2.18: Net Weight data of Chick Peas for the month of October.
Filling Weight of Chick Peas 205
210
208
210
208
209
209
209
208
209
209
209
209
207
208
209
209
208
208
209
208
209
208
208
210
208
210
209
210
209
209
209
208
Page | 67
Individual and Moving Range Charts for the Net Weight of Green Peas
Figure 2.58: Control chart for the net weight of green peas.
Comments:
Points are randomly scattered.
Process average is lower than for the chick peas.
92.3% of points within ± 1σ.
96.2% of points within ± 2σ.
Process is under control.
Page | 68
Table 2.19: Net Weight data for Green Peas for the month of October.
Net Weight of Green Peas 420
424
422
420
420
426
426
418
424
420
421
420
426
422
420
420
424
430
421
426
420
420
422
424
420
424
421
Page | 69
Individual and Moving Range Charts for the Filling Weight of Green Peas
Figure 2.59: Control chart for the filling weight of green peas.
Comments:
The nominal value for the green peas filling weight is 187.5 with a tolerance of ±2,5g.
Points are randomly scattered.
The process average is almost exactly equal to the nominal target. This is consistent with lower net weight than the chick peas where the filling weight average was close to the upper specification limit.
92.3% of points within ± 1σ.
92.3% of points within ± 2σ.
There is a reasonable amount of variation, with only one out of control point.
Page | 70
Table 2.20: Filling Weight data of Green Peas for the month of October.
Filling Weight of Green Peas 187
187
188
187
188
188
187
188
188
187
188
188
188
188
187
187
187
187
188
185
189
188
187
187
188
187
Page | 71
Conclusion
The runs of equal points dispersed in the control charts, and the center line of the filling weight chart for green peas, which corresponds to its nominal target, suggested that the process is indeed capable of producing cans with little variability in the filling weight. However, there seemed to be a lack of interest in correcting process shifts when they did occur. It was concluded that this was due to ignorance of the cost of consistently overfilling the cans. By studying the filling data for the month of October, the Cost Analysis group estimated that the company wastes around 68,000 KD annually by overfilling their cans.
Page | 72
2.4 New Quality Control Documentation
Considerations for designing the new sheets The sporadic nature of production means that some products are only produced for two hours a month, therefore recording only the averages will not suffice for the construction of proper control charts. It was decided that tests shall be carried out every 15 minutes as the rate of production (140 cans/min) is high, and to collect sufficient data to construct reliable control charts to monitor system performance. This resulted in eight subgroups per production run. The subgroup size had to be set so that a single production run would produce enough data points to construct individual control charts. However this couldn’t be done arbitrarily and therefore, statistical analysis was used in to determine the optimum subgroup size. There are two tolerance widths for the dry weights of the different products, 5 and 10 grams. The tighter width of 5 grams was used to base the subgroup size on, so that the quality sheets can be applied for all products. It was qualitatively determined that a change of one gram can be tolerated before a process mean shift needs to be recognized quickly as it would be close to the specification limit at that point. It was also decided that the product PH should be studied immediately after the cooking operation rather than wait until the production run is finished and the samples are sent to the labs. In this way, defects can be detected earlier and thus cumulative costs of poor quality reduced. With these considerations in mind, two quality control sheets, one for the filling weight and one for the finished products, measuring both the net weight and the PH, were created.
Page | 73
Statistical Analysis The number of standard deviations, k, was taken to be 1.5 because for the filling weight, σ = 0.7 i.e. the shift (kσ) is almost equal to 1g. Using this k value, β was found from the following graph:
Figure 2.60
Different parameters were calculated for subgroup sizes of 5 and 10 suing the following equations:
Average run length, the average number of subgroups before a shift of kσ is detected:
Page | 74
Average time to signal, the average time before the shift is detected:
The number of individual cans inspected before the process shift is detected:
Cost Considerations The combined salary of all quality personnel is 1170 KD per month, which works out to be 45KD per day. It takes 15 seconds to check each can’s weight, 30 seconds to check the temperature, and 30 seconds for transportation. There are 10 hours of production per day, and a sample is taken every fifteen minutes, therefore 40 checks per day. For a subgroup of 10 cans, it takes 6 minutes to carry out the tests. Therefore, the total time the personnel are engaged in quality tests is 240 minutes per day. This will cost: 240/600 * 45 = 18 KD/day. For a subgroup of 5 cans it takes 3.5 minutes to carry out the tests. Therefore, the total time the personnel are engaged in quality test is 140 minutes per day. This will cost: 140/600 * 45 = 10.5 KD/day.
Page | 75
Decision Table 2.21
n = 10
n=5
β
0.1
0.3
ARL
1.11
1.43
I
11.1
7.15
ATS
16.65
21.45
Cost (KD/day)
18
10.5
The Average Run Length for both subgroup sizes of 5 and 10 is smaller than 2.
I is smaller for n = 5.
Cost is almost half for n = 5.
Therefore the trade off of a slightly higher average run length is worth it and we shall consider n = 5 as our sample size.
Page | 76
Date:__ /__ /__ Production Run 1 Time #1
Time #2
Variant: Time #3
Time #4
Can Size(g): Time #5
Time #6
Time #7
Time #8
Can # 1 2 3 4 5 Avg
Production Run 2 Time #1
Time #2
Variant: Time #3
Time #4
Can Size(g): Time #5
Time #6
Time #7
Time #8
Can # 1 2 3 4 5 Avg
Production Run 3 Time #1
Time #2
Variant: Time #3
Time #4
Can Size(g): Time #5
Time #6
Time #7
Time #8
Can # 1 2 3 4 5 Avg
Figure 2.62: The new finished product quality sheet.
Page | 77
National Canned Food Company - Daniah
Q.C Department
Quality Sheet of (
)gm can
Date:
Can Production Date:
Variant:
Can Type:
Can #
Time #1: ……………….
Time #2: ……………….
Time #3: ……………….
Brine Temp:
Brine Temp:
Brine Temp:
Net Wt
PH
Net Wt
PH
Net Wt
Time #4: ………………. Brine Temp:
PH
Net Wt
PH
1 2 3 4 5 Average
Can #
Time #5: ……………….
Time #6: ……………….
Time #7: ……………….
Brine Temp:
Brine Temp:
Brine Temp:
Net Wt
PH
Net Wt
PH
Net Wt
Time #8: ………………. Brine Temp:
PH
Net Wt
1 2 3 4 5 Average
Other Defects Time #
Can #
Type:
Time #
Can #
Type:
Time #
Can #
Type:
Time #
Can #
Type:
Time #
Can #
Type:
Time #
Can #
Type:
Time #
Can #
Type:
Time #
Can #
Type:
Key:
SS: Seaming Steam
CW: Can Wash
C: Code
Page | 78
PH
2.5 New Sampling Plans
Proposed New Single Sampling Plan for Beans A new single sampling plan for beans was constructed using α and β values. The probability of acceptance had to be at least 95% for a lot with percent defective of 1 or less (i.e p is no larger 0.01). An attempt was made to achieved a Pa of 98% at p = 0.01, whilst making the Pa curve is sensitive enough to get a Pa no more than 5% at p = 0.10. α was set at 5%, whilst β was kept at 10%, in the following equations:
Using the relevant nomograph, the plan that came closest to meeting these constraints was the one with n = 70, and c = 2. Probablity of Acceptance for the New Beans Single Sampling Plan 1.00
Pa
0.80 0.60 0.40 0.20 0.00 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.63: Probability of acceptance for the new beans single sampling plan.
Page | 79
Table 2.22: Probability of acceptance for the new beans single sampling plan at different values of p.
p
Pa
0.01
0.9667
0.02
0.8350
0.03
0.6492
0.04
0.4656
0.05
0.3137
0.06
0.2013
0.07
0.1241
0.08
0.0740
0.09
0.0428
0.10
0.0242
Page | 80
AOQ
AOQ for the New Beans Single Sampling Plan 1.80% 1.60% 1.40% 1.20% 1.00% 0.80% 0.60% 0.40% 0.20% 0.00% 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p
Figure 2.64: AOQ for the new beans single sampling plan.
Table 2.23: AOQ for the new beans single sampling plan at different values of p.
p
AOQ
0.01
0.80%
0.02
1.38%
0.03
1.61%
0.04
1.54%
0.05
1.29%
0.06
1.00%
0.07
0.72%
0.08
0.49%
0.09
0.32%
0.10
0.20%
Page | 81
ATI
ATI for the New Beans Single Sampling Plan 450 400 350 300 250 200 150 100 50 0 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.65: ATI for the new beans single sampling plan.
Table 2.24: ATI for the new beans single sampling plan at different values of p.
p
ATI
0.01
81
0.02
124
0.03
186
0.04
246
0.05
296
0.06
334
0.07
359
0.08
376
0.09
386
0.10
392
Figure 2.65 shows that the Probability of acceptance became much more acceptable with a value of 96.67% at p =0.01 and decreasing very quickly, thereafter.
Page | 82
Comparison between the New Single Sampling and As-Is Plans For Beans To judge whether the new sampling plan is superior to the exising one, the P a curve did not siffice to make our decision. It also had to be verified that the cost of the new plan was lower at most values of p, by using the following equations:
Cost of poor quality = AOQ * cost of producing one unit * total annual production
Cost of inspection = ATI * hourly wage of quality personnel * average time to inspect one unit of raw material (in hours)
As mentioned in section 8, the hourly wages of the quality personnel is 4.5 KD.
The average time to inspect one bag of beans is 30 minutes.
The average time to inspect one tin sheet is 2 minutes.
Page | 83
Comparison between the Probability of Acceptance for the Beans As-Is and New Single Sampling Plans 1.00 0.80
Pa
0.60 0.40
New Single Sampling Plan
0.20
As is Plan
0.00 0
0.02
0.04
0.06
0.08
0.1
Lot fraction defective, p Figure 2.66: Comparison between the probability of acceptance for the beans as-is and the new single sampling plan. Table 2.25: Comparison between the probability of acceptance for the beans as-is and new single sampling plans at different values of p.
New Single p
As-Is
Sampling
0.01
0.8179
0.9667
0.02
0.6676
0.8350
0.03
0.5438
0.6492
0.04
0.4420
0.4656
0.05
0.3585
0.3137
0.06
0.2901
0.2013
0.07
0.2342
0.1241
0.08
0.1887
0.0740
0.09
0.1516
0.0428
0.10
0.1216
0.0242
Page | 84
AOQ
Comparison between the AOQ for the Beans As-Is and New Single Sampling Plans 1.80% 1.60% 1.40% 1.20% 1.00% 0.80% 0.60% 0.40% 0.20% 0.00%
New Single Sampling Plan As is Plan
0
0.02
0.04
0.06
0.08
0.1
Lot fraction defective, p Figure 2.67: Comparison between the AOQ for the beans as-is and the new single sampling plan.
Table 2.26: Comparison between the AOQ for the beans as-is and new single sampling plans at different values of p.
p
As-Is
New Single Sampling
0.01
0.78%
0.80%
0.02
1.27%
1.38%
0.03
1.55%
1.61%
0.04
1.68%
1.54%
0.05
1.70%
1.29%
0.06
1.65%
1.00%
0.07
1.56%
0.72%
0.08
1.43%
0.49%
0.09
1.30%
0.32%
0.10
1.15%
0.20%
Page | 85
Comparison between the ATI for the Beans As-Is and New Single Sampling Plans 500
ATI
400 300 200
New Single Sampling Plan
100
As is Plan
0 0
0.02
0.04
0.06
0.08
0.1
Lot fraction defective, p Figure 2.88: Comparison between the ATI for the beans as-is and the new single sampling plan.
Table 2.27: Comparison between the ATI for the beans as-is and new single sampling plan at different values of p.
p
As-Is
New Single Sampling
0.01
89
81
0.02
146
124
0.03
193
186
0.04
232
246
0.05
264
296
0.06
290
334
0.07
311
359
0.08
328
376
0.09
342
386
0.10
354
392
Page | 86
Cost
Comparison between Costs of the Beans As-Is and New Single Sampling Plans 60000 50000 40000 30000 20000 10000 0
New Single sampling Plan As-is plan 0
0.02 0.04 0.06 0.08 0.1
Lot fraction defective, p Figure 2.89: Comparison between the costs of the beans as-is and the new single sampling plan.
Table 9.28: Comparison between the costs of the beans as-is and new single sampling plan at different values of p.
p
As-Is
New Single Sampling
0.01
23595
24194
0.02
38521
41761
0.03
47098
48798
0.04
51093
46811
0.05
51863
39632
0.06
50440
30752
0.07
47600
22386
0.08
43916
15545
0.09
39808
10445
0.1
35571
6889
As is clear from figure 2.89, the cost of the new single sampling plan is lower for most values of p. Page | 87
2.6 Proposed Double Sampling Plans For Beans After construtcing the new sampling plan, the possibility of constructing a superior double sampling plan that will reduce the cost of sampling but still meet the target of having a Pa no less than 95% when p = 0.01, was also considered. Six different double sampling plans were tested and the best was chosen based on the total cost of the plan. Calculations of the paramters for the double sampling plans were made usin the following equations:
The parameters for the six plans are summarized as follows:. Table 9.29: Summary of the parameters of the six proposed beans double sampling plans
Plan 1
Plan 2
Plan 3
Plan 4
Plan 5
Plan 6
n1
10
15
20
25
30
35
n2
30
45
60
75
90
60
c1
0
0
0
0
0
0
c2
2
2
2
2
2
2
Where: n1: Size of the first sample. n2: Size of the second sample. c1: The number of defects tolerated in the first sample without a need for the second sample. c2: The number of defects tolerated in both samples, combined, before the lot is rejected. Page | 88
Probablity of Acceptance for the First Proposed Beans Sampling Plan 1.00 0.80
Pa
0.60 0.40 0.20 0.00 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.90: Probability of acceptance for the first proposed beans sampling plan.
Table 2.30: Probability of acceptance for the first proposed beans sampling plan at different values of.
p
Pa
0.01
0.9955
0.02
0.9721
0.03
0.9265
0.04
0.8633
0.05
0.7892
0.06
0.7106
0.07
0.6325
0.08
0.5582
0.09
0.4898
0.10
0.4281
Page | 89
AOQ
AOQ for the First Proposed Beans Sampling Plan 4.50% 4.00% 3.50% 3.00% 2.50% 2.00% 1.50% 1.00% 0.50% 0.00% 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.91: AOQ for the first proposed beans sampling plan.
Table 2.31: AOQ for the first proposed beans sampling plan at different values of p.
p
AOQ
0.01
0.96%
0.02
1.87%
0.03
2.67%
0.04
3.31%
0.05
3.78%
0.06
4.08%
0.07
4.24%
0.08
4.28%
0.09
4.23%
0.10
4.11%
Page | 90
ATI for the First Proposed Beans Sampling Plan 250 200
ATI
150 100 50 0 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.92: ATI for the first proposed beans sampling plan. Table 2.32: ATI for the first proposed beans sampling plan at different values of p.
p
ATI
0.01
14
0.02
26
0.03
44
0.04
69
0.05
98
0.06
128
0.07
158
0.08
186
0.09
212
0.10
235
Page | 91
Probability of Acceptance for the Second Proposed Beans Sampling Plan 1.00
Pa
0.80 0.60 0.40 0.20 0.00 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p
Figure 2.93: Probability of acceptance for the second proposed beans sampling plan.
Table 2.33: Probability of acceptance for the 2nd proposed beans sampling plan at different values of p.
p
Pa
0.01
0.9865
0.02
0.9263
0.03
0.8278
0.04
0.7130
0.05
0.5992
0.06
0.4963
0.07
0.4080
0.08
0.3347
0.09
0.2748
0.10
0.2262
Page | 92
AOQ for the Second Proposed Beans Sampling Plan 3.00% 2.50%
AOQ
2.00% 1.50% 1.00% 0.50% 0.00% 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p
Figure 2.94: AOQ for the second proposed beans sampling plan.
Table 2.34: AOQ for the second proposed beans sampling plan at different values of p
p
AOQ
0.01
0.94%
0.02
1.74%
0.03
2.32%
0.04
2.67%
0.05
2.81%
0.06
2.80%
0.07
2.69%
0.08
2.53%
0.09
2.35%
0.10
2.15%
.
Page | 93
ATI for the Second Proposed Beans Sampling Plan 350 300
ATI
250 200 150 100 50 0 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.95: ATI for the second proposed beans sampling plan.
Table 2.35: ATI for the second proposed beans sampling plan at different values of p.
p
ATI
0.01
26
0.02
52
0.03
90
0.04
133
0.05
175
0.06
213
0.07
246
0.08
273
0.09
296
0.10
314
Page | 94
Probability of Acceptance for the Third Proposed Beans Sampling Plan 1.00 0.80
Pa
0.60 0.40 0.20 0.00 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p
Figure 2.96: Probability of acceptance for the third proposed beans sampling plan.
Table 2.36: Probability of acceptance for the third proposed beans sampling plan at different values of p.
p
Pa
0.01
0.9718
0.02
0.8637
0.03
0.7142
0.04
0.5659
0.05
0.4395
0.06
0.3393
0.07
0.2625
0.08
0.2042
0.09
0.1599
0.10
0.1258
Page | 95
AOQ for the Third Proposed Beans Sampling Plan 2.50%
AOQ
2.00% 1.50% 1.00% 0.50% 0.00% 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p
Figure 2.97: AOQ for the third proposed beans sampling plan.
Table 2.37: AOQ for different values of p for the third proposed beans sampling plan.
p
AOQ
0.01
0.90%
0.02
1.58%
0.03
1.96%
0.04
2.08%
0.05
2.03%
0.06
1.89%
0.07
1.72%
0.08
1.53%
0.09
1.36%
0.10
1.19%
Page | 96
ATI for the Third Proposed Beans Sampling Plan 400 350 300
ATI
250 200 150 100 50 0 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.98: ATI for the third proposed beans sampling plan.
Table 2.38: ATI for different values of p for the third proposed beans sampling plan.
p
ATI
0.01
40
0.02
84
0.03
139
0.04
192
0.05
238
0.06
274
0.07
302
0.08
323
0.09
340
0.10
352
Page | 97
Probablity of Acceptance for the Fourth Proposed Beans Sampling Plan 1.00 0.80
Pa
0.60 0.40 0.20 0.00 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.99: Probability of acceptance for the fourth proposed beans sampling plan
Table 2.39: Probability of acceptance for the fourth proposed beans sampling plan at different values of p.
p
Pa
0.01
0.9515
0.02
0.7913
0.03
0.6027
0.04
0.4417
0.05
0.3209
0.06
0.2344
0.07
0.1730
0.08
0.1288
0.09
0.0965
0.10
0.0726
Page | 98
AOQ
AOQ for the Fourth Proposed Beans Sampling Plan 1.80% 1.60% 1.40% 1.20% 1.00% 0.80% 0.60% 0.40% 0.20% 0.00% 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p
Figure 2.100: AOQ for the fourth proposed beans sampling plan.
Table 2.40: AOQ for the fourth proposed beans sampling plan at different values of p.
p
AOQ
0.01
0.86%
0.02
1.41%
0.03
1.62%
0.04
1.60%
0.05
1.46%
0.06
1.29%
0.07
1.12%
0.08
0.96%
0.09
0.81%
0.10
0.68%
Page | 99
ATI for the Fourth Proposed Beans Sampling Plan 400 350 300
ATI
250 200 150 100 50 0 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.101: ATI for the fourth proposed beans sampling plan.
Table 2.41: ATI for the fourth proposed beans sampling plan at different values of p.
p
ATI
0.01
56
0.02
117
0.03
184
0.04
240
0.05
283
0.06
314
0.07
336
0.08
352
0.09
364
0.10
373
Page | 100
Probablity of Acceptance for the Fifth Proposed Beans Sampling Plan 1.00 0.80
Pa
0.60 0.40 0.20 0.00 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.102: Probability of acceptance for the fifth proposed beans sampling plan.
Table 2.42: Probability of acceptance for the fifth proposed beans sampling plan at different values of p.
p
Pa
0.01
0.9262
0.02
0.7153
0.03
0.5025
0.04
0.3438
0.05
0.2364
0.06
0.1650
0.07
0.1167
0.08
0.0832
0.09
0.0595
0.10
0.0425
Page | 101
AOQ for the Fifth Proposed Beans Sampling Plan 1.40% 1.20%
AOQ
1.00% 0.80% 0.60% 0.40% 0.20% 0.00% 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.103: AOQ for the fifth proposed beans sampling plan.
Table 2.42: AOQ for the fifth proposed beans sampling plan at different values of p.
p
AOQ
0.01
0.81%
0.02
1.25%
0.03
1.33%
0.04
1.23%
0.05
1.07%
0.06
0.90%
0.07
0.75%
0.08
0.61%
0.09
0.49%
0.10
0.39%
Page | 102
ATI
ATI for the Fifth Proposed Beans Sampling Plan 450 400 350 300 250 200 150 100 50 0 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p
Figure 2.104: ATI for the fifth proposed beans sampling plan.
Table 2.43: ATI for the fifth proposed beans sampling plan at different values of p.
p
ATI
0.01
74
0.02
151
0.03
223
0.04
277
0.05
314
0.06
340
0.07
357
0.08
369
0.09
378
0.10
384
Page | 103
Probablity of Acceptance for the Sixth Proposed Beans Sampling Plan 1.00
Pa
0.80 0.60 0.40 0.20 0.00 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.105: Probability of acceptance for the sixth proposed beans sampling plan. Table 2.44: Probability of acceptance for the sixth proposed beans sampling plan at different values of p.
p
Pa
0.01
0.9506
0.02
0.7794
0.03
0.5696
0.04
0.3876
0.05
0.2533
0.06
0.1624
0.07
0.1035
0.08
0.0662
0.09
0.0426
0.10
0.0277
Page | 104
AOQ for the Sixth Proposed Beans Sampling Plan 1.40% 1.20%
AOQ
1.00% 0.80% 0.60% 0.40% 0.20% 0.00% 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.106: AOQ for the sixth proposed beans sampling plan.
Table 2.44: AOQ for the sixth proposed beans sampling plan at different values of p.
p
AOQ
0.01
0.83%
0.02
1.34%
0.03
1.47%
0.04
1.33%
0.05
1.10%
0.06
0.85%
0.07
0.64%
0.08
0.47%
0.09
0.34%
0.10
0.25%
Page | 105
ATI
ATI for the Sixth Proposed Beans Sampling Plan 450 400 350 300 250 200 150 100 50 0 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.107: ATI for the sixth proposed beans sampling plan.
Table 2.45: ATI f for the sixth proposed beans sampling plan at different values of p.
p
ATI
0.01
67
0.02
131
0.03
204
0.04
267
0.05
312
0.06
343
0.07
364
0.08
377
0.09
385
0.10
390
Page | 106
Comparison between the Proposed Double Sampling Plans for Beans
Pa
Comparison between the Probablity of Acceptance for the Proposed Beans Double Sampling Plans 1.00 0.80 0.60 0.40 0.20 0.00
Plan 1 Plan 2 Plan 3 Plan 4 0.00
0.02
0.04
0.06
0.08
Plan 5
0.10
Plan 6
Lot fraction defective, p
Figure 2.108: Comparison between the probability of acceptance for the proposed beans double sampling plans. Table 2.46: Comparison between the probability of acceptance for the proposed beans double sampling plans at different values of p.
p
Plan 1
Plan 2
Plan 3
Plan 4
Plan 5
Plan 6
0.01
0.9955
0.9865
0.9718
0.9515
0.9262
0.9506
0.02
0.9721
0.9263
0.8637
0.7913
0.7153
0.7794
0.03
0.9265
0.8278
0.7142
0.6027
0.5025
0.5696
0.04
0.8633
0.7130
0.5659
0.4417
0.3438
0.3876
0.05
0.7892
0.5992
0.4395
0.3209
0.2364
0.2533
0.06
0.7106
0.4963
0.3393
0.2344
0.1650
0.1624
0.07
0.6325
0.4080
0.2625
0.1730
0.1167
0.1035
0.08
0.5582
0.3347
0.2042
0.1288
0.0832
0.0662
0.09
0.4898
0.2748
0.1599
0.0965
0.0595
0.0426
0.10
0.4281
0.2262
0.1258
0.0726
0.0425
0.0277
Page | 107
AOQ
Comparison between the AOQ for the Proposed Beans Double Sampling Plans 4.50% 4.00% 3.50% 3.00% 2.50% 2.00% 1.50% 1.00% 0.50% 0.00%
Plan 1 Plan 2 Plan 3 Plan 4 Plan 5 0.00
0.02
0.04
0.06
0.08
0.10
Plan 6
Lot fraction defective, p Figure 2.109: Comparison between the AOQ for the proposed beans double sampling plans.
Table 2.47 : Comparison between the AOQ for the proposed beans double sampling plans at different values of p.
p
Plan 1
Plan 2
Plan 3
Plan 4
Plan 5
Plan 6
0.01
0.96%
0.94%
0.90%
0.86%
0.81%
0.83%
0.02
1.87%
1.74%
1.58%
1.41%
1.25%
1.34%
0.03
2.67%
2.32%
1.96%
1.62%
1.33%
1.47%
0.04
3.31%
2.67%
2.08%
1.60%
1.23%
1.33%
0.05
3.78%
2.81%
2.03%
1.46%
1.07%
1.10%
0.06
4.08%
2.80%
1.89%
1.29%
0.90%
0.85%
0.07
4.24%
2.69%
1.72%
1.12%
0.75%
0.64%
0.08
4.28%
2.53%
1.53%
0.96%
0.61%
0.47%
0.09
4.23%
2.35%
1.36%
0.81%
0.49%
0.34%
0.10
4.11%
2.15%
1.19%
0.68%
0.39%
0.25%
Page | 108
ATI
Comparison between the ATI for the Proposed Beans Double Sampling Plans 400 350 300 250 200 150 100 50 0
Plan 1 Plan 2 Plan 3 Plan 4 Plan 5 0.00
0.02
0.04
0.06
0.08
0.10
Plan 6
Lot fraction defective, p Figure 2.110: Comparison between the ATI for the proposed beans double sampling plans.
Table 2.48: Comparison between the ATI for the proposed beans double sampling plans at different values of p.
p
Plan 1
Plan 2
Plan 3
Plan 4
Plan 5
Plan 6
0.01
14
26
40
56
74
67
0.02
26
52
84
117
151
131
0.03
44
90
139
184
223
204
0.04
69
133
192
240
277
267
0.05
98
175
238
283
314
312
0.06
128
213
274
314
340
343
0.07
158
246
302
336
357
364
0.08
186
273
323
352
369
377
0.09
212
296
340
364
378
385
0.10
235
314
352
373
384
390
Page | 109
Comparison between the Costs of the Proposed Beans Double Sampling Plans 140000 120000 Plan 1
80000
Plan 2
60000
Plan 3
Cost
100000
40000
Plan 4
20000
Plan 5
0 0.00
0.02
0.04
0.06
0.08
0.10
Plan 6
Lot fraction defective, p Figure 2.111: Comparison between the costs of the proposed beans double sampling plans. Table 2.49: Comparison between costs for the proposed beans double sampling plans at different values of p.
p
Plan 1
Plan 2
Plan 3
Plan 4
Plan 5
Plan 6
0.01
29,051
28,218
27,191
26,003
24,698
25,244
0.02
56,430
52,533
47,826
42,813
37,881
40,750
0.03
80,411
70,196
59,285
49,151
40,427
44,610
0.04
99,730
80,633
62,942
48,574
37,567
40,747
0.05
113,907
84,916
61,557
44,693
32,892
33,696
0.06
123,125
84,717
57,508
39,676
27,982
26,354
0.07
127,985
81,630
52,341
34,537
23,393
20,011
0.08
129,281
76,896
46,898
29,680
19,294
14,993
0.09
127,834
71,365
41,588
25,246
15,730
11,193
0.1
124,397
65,568
36,588
21,281
12,699
8,377
Page | 110
As can be seen from figure 2.111, plans 5 and 6 have the lowest total costs. Plan 6 was deemed to the best because it also satisfied the constraint of Pa being at least 95% at p = 0.01.
Comparison between the As-is and Double Sampling Plans For Beans
Pa
Comparison between the Probability of Acceptance for the Beans As-Is and Double Sampling Plans 1.00 0.80 0.60 0.40 0.20 0.00
Double sampling plan 0 0.02 0.04 0.06 0.08 0.1
As is Plan
Lot fraction defective, p Figure 2.112: Comparison between the probability of acceptance for beans as-is and double sampling plans.
Table 2.50: Comparison between the probability of acceptance for the beans as- is and double sampling plans at different values of p.
p
As-Is
Double Sampling
0.01
0.8179
0.9506
0.02
0.6676
0.7794
0.03
0.5438
0.5696
0.04
0.4420
0.3876
0.05
0.3585
0.2533
0.06
0.2901
0.1624
0.07
0.2342
0.1035
0.08
0.1887
0.0662
0.09
0.1516
0.0426
0.10
0.1216
0.0277
Page | 111
AOQ
Comparison between the AOQ for the Beans As-Is and Double Sampling Plans 1.80% 1.60% 1.40% 1.20% 1.00% 0.80% 0.60% 0.40% 0.20% 0.00%
Double sampling plan As is Plan
0
0.02
0.04
0.06
0.08
0.1
Lot fraction defective, p
Figure 2.113: Comparison between the AOQ for the beans as-is and double sampling plans.
Table 2.52: Comparison between the ATI for the beans as- is and double sampling plans at different Double p
As-Is
Sampling
0.01
0.78%
0.83%
0.02
1.27%
1.34%
0.03
1.55%
1.47%
0.04
1.68%
1.33%
0.05
1.70%
1.10%
0.06
1.65%
0.85%
0.07
1.56%
0.64%
0.08
1.43%
0.47%
0.09
1.30%
0.34%
0.10
1.15%
0.25%
Page | 112
ATI
Comparison between the ATI for the Beans As-Is and Double Sampling Plans 450 400 350 300 250 200 150 100 50 0
Double sampling plan As is Plan
0
0.02
0.04
0.06
0.08
0.1
Lot fraction defective, p Figure 2.114: Comparison between the ATI for the beans as-is and double sampling plans.
Table 2.51: Comparison between the AOQ for the beans as- is and double sampling plan at different values of p.
p
As-Is
Double Sampling
0.01
89
67
0.02
146
131
0.03
193
204
0.04
232
267
0.05
264
312
0.06
290
343
0.07
311
364
0.08
328
377
0.09
342
385
0.10
354
390
values of p.
Page | 113
Comparison between Costs of the Beans As-Is and Double Sampling Plans Cost
60000 40000
Double sampling plan
20000 0
As-is plan 0 0.02 0.04 0.06 0.08 0.1 Lot fraction defective, p
Figure 2.115: Comparison between costs of the beans as-is and double sampling plans.
Table 2.53: Comparison between the costs of the beans as- is and double sampling plans at different values of p
p
As-Is
Double Sampling
0.01
23,595
25,244
0.02
38,521
40,750
0.03
47,098
44,610
0.04
51,093
40,747
0.05
51,863
33,696
0.06
50,440
26,354
0.07
47,600
20,011
0.08
43,916
14,993
0.09
39,808
11,193
0.1
35,571
8,377 .
Figure 2.115 shows that the cost of the double sampling plan is less than that of the as-is plan. Therefore, the cost of the double sampling was compared with that of the new single sampling plan the one with minimum cost was chosen. Page | 114
Comparison between Costs of the Beans New Single Sampling and Double Sampling Plans
Cost
60000 40000 Double sampling plan
20000
New Single sampling plan
0 0 0.02 0.04 0.06 0.08 0.1
Lot fraction defective, p Figure 2.116: Comparison between costs of the beans as-is and double sampling plans.
p
Double Sampling
New Single Sampling
0.01
25,244
24,194
0.02
40,750
41,761
0.03
44,610
48,798
0.04
40,747
46,811
0,05
33,696
39,632
0.06
26,354
30,752
0.07
20,011
22,386
0.08
14,993
15,545
0.09
11,193
10,445
0.1
8,377
6,889
Table 2.54: Comparison between the costs of the beans new single sampling and double sampling plans at different values of p.
As figure 2.116 shows, the double sampling plan gives a lower cost for most values of p. Therefore, the double sampling plan should be implemented.
Page | 115
2.7 Proposed New Single Sampling Plan for Tin Sheets As with the case of the beans, a new single sampling plan was developed using the nomograph and setting α to 5% and β to 10%: Therefore, the same plan of n = 70 and c = 2 was used. Probablity of Acceptance for the New Tin Sheets Single Sampling Plan 1.00
Pa
0.80 0.60 0.40 0.20 0.00 0
0.02
0.04
0.06
0.08
0.1
Lot fraction defective, p Figure 2.117: Probability of acceptance for the new tin sheets single sampling plan. Table 2.55: Probability of acceptance for the new tin sheets single sampling plan at different values of p.
p
Pa
0.01
0.9667
0.02
0.8350
0.03
0.6492
0.04
0.4656
0.05
0.3137
0.06
0.2013
0.07
0.1241
0.08
0.0740
0.09
0.0428
0.1
0.0242
Page | 116
AOQ for the New Tin Sheets Single Sampling Plan 2.50%
AOQ
2.00% 1.50% 1.00% 0.50% 0.00% 0
0.02
0.04
0.06
0.08
0.1
Lot fraction defective, p Figure 2.118: AOQ for the new tin sheets single sampling plan.
Table 2.56: AOQ for the new tin sheets single sampling plan at different values of p.
p
AOQ
0.01
0.97%
0.02
1.67%
0.03
1.95%
0.04
1.86%
0.05
1.57%
0.06
1.21%
0.07
0.87%
0.08
0.59%
0.09
0.39%
0.1
0.24%
Page | 117
ATI
ATI for the New Tin Sheets Single Sampling Plan 450,000 400,000 350,000 300,000 250,000 200,000 150,000 100,000 50,000 0 0
0.02
0.04
0.06
0.08
0.1
Lot fraction defective, p
Figure 2.119: ATI for the new tin sheets single sampling plan.
Table 2.57: ATI for the new tin sheets single sampling plan at different values of p.
p
ATI
0.01
14,073
0.02
69,367
0.03
147,366
0.04
224,498
0.05
288,253
0.06
335,467
0.07
367,887
0.08
388,935
0.09
402,011
0.1
409,846
Page | 118
Comparison between the New Single Sampling and As-Is Plans For Tin Sheets Comparison between the Probability of Acceptance for the Tin Sheets As-Is and New Single Sampling Plans 1.00
Pa
0.80 0.60
New Single Sampling Plan
0.40 0.20
As is Plan
0.00 0
0.02
0.04
0.06
0.08
0.1
Lot fraction defective, p Figure 2.120: Comparison between the probability of acceptance for the tin sheets as-is and new single sampling plans.
Table 2.58: Comparison between the probability of acceptance for the tin sheets as-is and new single sampling plans at different values of p.
New Single p
As-Is
Sampling
0.01
0.9044
0.9667
0.02
0.8171
0.8350
0.03
0.7374
0.6492
0.04
0.6648
0.4656
0.05
0.5987
0.3137
0.06
0.5386
0.2013
0.07
0.4840
0.1241
0.08
0.4344
0.0740
0.09
0.3894
0.0428
0.10
0.3487
0.0242 Page | 119
Comparison between the AOQ for the Tin Sheets As-Is and New Single Sampling Plans 3.50% 3.00%
AOQ
2.50% 2.00%
New Single Sampling Plan
1.50% 1.00%
As is Plan
0.50% 0.00% 0
0.02
0.04
0.06
0.08
0.1
Lot fraction defective, p
Figure 2.121: Comparison between the AOQ for the tin sheets as-is and new single sampling plans.
Table 2.59: Comparison between the AOQ for the tin sheets as-is and new single sampling plans at different values of p.
New Single p
As-Is
Sampling
0.01
0.90%
0.97%
0.02
1.63%
1.67%
0.03
2.21%
1.95%
0.04
2.95%
1.86%
0.05
2.99%
1.57%
0.06
2.69%
1.21%
0.07
2.42%
0.87%
0.08
2.17%
0.59%
0.09
1.95%
0.39%
0.10
1.74%
0.24%
Page | 120
ATI
Comparison between the ATI for the Tin Sheets AsIs and New Single Sampling Plans 450000 400000 350000 300000 250000 200000 150000 100000 50000 0
New Single Sampling Plan As is Plan
0
0.02
0.04
0.06
0.08
0.1
Lot fraction defective, p
Figure 2.122: Comparison between the ATI for the tin sheets as-is and new single sampling plans.
Table 2.60: Comparison between the ATI for the tin sheets as-is and new single sampling plans at different values of p.
p
As-Is
New Single Sampling
0.01
40,169
14,073
0.02
76,838
69,367
0.03
110,289
147,366
0.04
140,777
224,498
0.05
168,536
288,253
0.06
193,787
335,467
0.07
216,732
367,887
0.08
237,561
388,935
0.09
256,449
402,011
0.1
273,559
409,846
Page | 121
Total cost
Comparison between Costs of the Tin Sheets As-Is and New Single Sampling Plan 100000 50000 0
New Single sampling Plan 00.02 0.04 0.06 0.080.1
As-is plan
Lot fraction defetive, p
Figure 2.123: Comparison between the costs of the tin sheets as-is and new single sampling plan.
Table 2.61: Comparison between the costs of the tin sheets as-is and new single sampling plans at different values of p.
p
As-Is
New Single Sampling
0.01
22,063
21,414
0.02
40,184
40,373
0.03
54,871
52,073
0.04
72,691
56,058
0.05
75,699
54,657
0.06
71,261
50,598
0.07
67,228
45,887
0.08
63,567
41,634
0.09
60,247
38,271
0.1
57,240
35,831
As figure 2.123 shows, the new single sampling plan has a much better Pa curve, with a value of 96.67% at p=.01 and much higher sensitivity to an increase in p. The total cost of the new plan is also smaller.
Page | 122
2.8 Proposed Double Sampling Plans For Tin Sheets Once again, six different double sampling plans were tested with the best plan chosen based on its total cost. The following table summarizes the paramters of the six proposed plans: Table 2.62: Summary of the parameters of the six proposed tin sheets double sampling plans
Plan 1
Plan 2
Plan 3
Plan 4
Plan 5
Plan 6
n1
5
10
10
15
20
35
n2
50
100
150
150
150
55
c1
0
0
0
0
0
0
c2
2
2
2
2
2
2
.
Page | 123
Probablity of Acceptance for the First Proposed Tin Sheets Sampling Plan 1.00 0.80
Pa
0.60 0.40 0.20 0.00 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p
Figure 2.124: Probability of acceptance for the first proposed tin sheets sampling plan.
Table 2.63: Probability of acceptance for the first proposed tin sheets sampling plan at different values of p.
p
Pa
0.01
0.9953
0.02
0.9732
0.03
0.9343
0.04
0.8852
0.05
0.8323
0.06
0.7798
0.07
0.7299
0.08
0.6836
0.09
0.6410
0.10
0.6019
Page | 124
AOQ
AOQ for the First Proposed Tin Sheets Sampling Plan 4.00% 3.50% 3.00% 2.50% 2.00% 1.50% 1.00% 0.50% 0.00% 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.125: AOQ for the first proposed tin sheets sampling plan.
Table 2.64: AOQ for the first proposed tin sheets sampling plan at different values of p.
p
AOQ
0.01
1.00%
0.02
1.95%
0.03
2.80%
0.04
3.54%
0.05
4.16%
0.06
4.68%
0.07
5.11%
0.08
5.47%
0.09
5.77%
0.10
6.02%
Page | 125
ATI for the First Proposed Tin Sheets Sampling Plan 300,000 250,000
ATI
200,000 150,000 100,000 50,000 0 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.126: ATI for the first proposed tin sheets sampling plan.
Table 2.65: Probability of acceptance for the first proposed tin sheets sampling plan at different values of p.
p
ATI
0.01
1,976
0.02
11,282
0.03
27,618
0.04
48,207
0.05
70,429
0.06
92,506
0.07
113,467
0.08
132,912
0.09
150,781
0.10
167,185
Page | 126
Probablity of Acceptance for the Second Proposed Tin Sheets Sampling Plan 1.00 0.80
Pa
0.60 0.40 0.20 0.00 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.127: Probability of acceptance for the second proposed tin sheets sampling plan.
Table 2.66: Probability of acceptance for the second proposed tin sheets sampling plan at different values of p.
p
Pa
0.01
0.9731
0.02
0.8863
0.03
0.7833
0.04
0.6899
0.05
0.6109
0.06
0.5440
0.07
0.4863
0.08
0.4353
0.09
0.3898
0.10
0.3488
Page | 127
AOQ
AOQ for the Second Proposed Tin Sheets Sampling Plan 4.00% 3.50% 3.00% 2.50% 2.00% 1.50% 1.00% 0.50% 0.00% 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.128: AOQ for the second proposed tin sheets sampling plan.
Table 2.67: AOQ for the second proposed tin sheets sampling plan at different values of p.
p
AOQ
0.01
0.97%
0.02
1.77%
0.03
2.35%
0.04
2.76%
0.05
3.05%
0.06
3.26%
0.07
3.40%
0.08
3.48%
0.09
3.51%
0.10
3.49%
Page | 128
ATI for the Second Proposed Tin Sheets Sampling Plan 300,000 250,000
ATI
200,000 150,000 100,000 50,000 0 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.129: ATI for the second proposed tin sheets sampling plan.
Table 2.66: ATI of acceptance for the third proposed tin sheets sampling plan at different values
p
ATI
0.01
11,308
0.02
47,749
0.03
91,018
0.04
130,271
0.05
163,444
0.06
191,512
0.07
215,776
0.08
237,178
0.09
256,302
0.10
273,504
Page | 129
Probablity of Acceptance for the Third Proposed Tin Sheets Sampling Plan 1.00
Pa
0.80 0.60 0.40 0.20 0.00 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.130: Probability of acceptance for the third proposed tin sheets sampling plan.
Table 2.67: Probability of acceptance for the third proposed tin sheets sampling plan at different values of p.
p
Pa
0.01
0.9562
0.02
0.8505
0.03
0.7511
0.04
0.6693
0.05
0.6000
0.06
0.5390
0.07
0.4841
0.08
0.4344
0.09
0.3894
0.10
0.3487
Page | 130
AOQ
AOQ for the Third Proposed Tin Sheets Sampling Plan 4.00% 3.50% 3.00% 2.50% 2.00% 1.50% 1.00% 0.50% 0.00% 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.131 : AOQ for the third proposed tin sheets sampling plan.
Table 2.68: AOQ for the third proposed tin sheets sampling plan at different values of p.
P
AOQ
0.01
0.96%
0.02
1.70%
0.03
2.25%
0.04
2.68%
0.05
3.00%
0.06
3.23%
0.07
3.39%
0.08
3.48%
0.09
3.50%
0.10
3.49%
Page | 131
ATI for the Third Proposed Tin Sheets Sampling Plan 300,000 250,000
ATI
200,000 150,000 100,000 50,000 0 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.132: ATI for the third proposed tin sheets sampling plan.
Table 2.69: ATI of acceptance for the third proposed tin sheets sampling plan at different values
p
ATI
0.01
18,420
0.02
62,796
0.03
104,552
0.04
138,882
0.05
167,986
0.06
193,641
0.07
216,696
0.08
237,553
0.09
256,447
0.10
273,558
Page | 132
Probablity of Acceptance for the Fourth Proposed Tin Sheets Sampling Plan 1.00 0.80
Pa
0.60 0.40 0.20 0.00 0.0000
0.0200
0.0400
0.0600
0.0800
0.1000
Lot fraction defective, p
Figure 2.133: Probability of acceptance for the fourth proposed tin sheets sampling plan.
Table 2.70: Probability of acceptance for the fourth proposed tin sheets sampling plan at different values of p.
p
Pa
0.01
0.9347
0.02
0.7845
0.03
0.6511
0.04
0.5477
0.05
0.4648
0.06
0.3957
0.07
0.3368
0.08
0.2863
0.09
0.2430
0.10
0.2059
Page | 133
AOQ for the Fourth Proposed Tin Sheets Sampling Plan 2.50%
AOQ
2.00% 1.50% 1.00% 0.50% 0.00% 0.0000
0.0200
0.0400
0.0600
0.0800
0.1000
Lot fraction defective, p
Table 2.71: AOQ for the fourth proposed tin sheets sampling plan at different values of p.
p
AOQ
0.01
0.93%
0.02
1.57%
0.03
1.95%
0.04
2.19%
0.05
2.32%
0.06
2.37%
0.07
2.36%
0.08
2.29%
0.09
2.19%
0.10
2.06%
Page | 134
ATI
ATI for the Fourth Proposed Tin Sheets Sampling Plan 400,000 350,000 300,000 250,000 200,000 150,000 100,000 50,000 0 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.134: ATI for the fourth proposed tin sheets sampling plan.
Table 2.72: ATI for the fourth proposed tin sheets sampling plan at different values of p.
p
ATI
0.01
27,459
0.02
90,539
0.03
146,555
0.04
189,981
0.05
224,777
0.06
253,820
0.07
278,552
0.08
299,751
0.09
317,938
0.10
333,528
Page | 135
Probablity of Acceptance for the Fifth Proposed Tin Sheets Sampling Plan 1.00 0.80
Pa
0.60 0.40 0.20 0.00 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.135: Probability of acceptance for the fifth proposed tin sheets sampling plan.
Table 2.73: Probability of acceptance for the fifth proposed tin sheets sampling plan at different values of p.
p
Pa
0.01
0.9135
0.02
0.7236
0.03
0.5645
0.04
0.4482
0.05
0.3601
0.06
0.2905
0.07
0.2343
0.08
0.1887
0.09
0.1516
0.10
0.1216
Page | 136
AOQ for the Fifth Proposed Tin Sheets Sampling Plan 2.00%
AOQ
1.50% 1.00% 0.50% 0.00% 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.136: AOQ for the fifth proposed tin sheets sampling plan.
Table 2.74: AOQ for the fifth proposed tin sheets sampling plan at different values of p.
p
AOQ
0.01
0.91%
0.02
1.45%
0.03
1.69%
0.04
1.79%
0.05
1.80%
0.06
1.74%
0.07
1.64%
0.08
1.51%
0.09
1.36%
0.10
1.22%
Page | 137
ATI for the Fifth Proposed Tin Sheets Sampling Plan 400,000 350,000 300,000
ATI
250,000 200,000 150,000 100,000 50,000 0 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.137: ATI for the fifth proposed tin sheets sampling plan.
Table 2.75: ATI for the fifth proposed tin sheets sampling plan at different values of p.
p
ATI
0.01
36,383
0.02
116,108
0.03
182,929
0.04
231,777
0.05
268,765
0.06
297,999
0.07
321,588
0.08
340,745
0.09
356,311
0.10
368,940
Page | 138
Probablity of Acceptance for the Sixth Proposed Tin Sheets Sampling Plan 1.00 0.80
Pa
0.60 0.40 0.20 0.00 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p
Figure 2.138: Probability of acceptance for the sixth proposed tin sheets sampling plan.
Table 2.76: Probability of acceptance for the sixth proposed tin sheets sampling plan at different values of p.
p
Pa
0.01
0.9506
0.02
0.7794
0.03
0.5696
0.04
0.3876
0.05
0.2533
0.06
0.1624
0.07
0.1035
0.08
0.0662
0.09
0.0426
0.10
0.0277
Page | 139
AOQ
AOQ for the Sixth Proposed Tin Sheets Sampling Plan 1.80% 1.60% 1.40% 1.20% 1.00% 0.80% 0.60% 0.40% 0.20% 0.00% 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.139: AOQ for the sixth proposed tin sheets sampling plan.
Table 2.77: AOQ for the sixth proposed tin sheets sampling plan at different values of p.
p
AOQ
0.01
0.95%
0.02
1.56%
0.03
1.71%
0.04
1.55%
0.05
1.27%
0.06
0.97%
0.07
0.72%
0.08
0.53%
0.09
0.38%
0.10
0.28%
Page | 140
ATI
ATI for the Sixth Propsed Tin Sheets Sampling Plan 450,000 400,000 350,000 300,000 250,000 200,000 150,000 100,000 50,000 0 0.00
0.02
0.04
0.06
0.08
0.10
Lot fraction defective, p Figure 2.140: ATI for the sixth proposed tin sheets sampling plan.
Table 2.78: ATI for the sixth proposed tin sheets sampling plan at different values of p.
p
ATI
0.01
20,796
0.02
92,709
0.03
180,801
0.04
257,219
0.05
313,617
0.06
351,813
0.07
376,531
0.08
392,202
0.09
402,093
0.1
408,368
Page | 141
Comparison between the Proposed Double Sampling Plans for Tin Sheets Comparison between the Probablity of Acceptance for the Proposed Beans Double Sampling Plans 1.00
Pa
0.80
Plan 1
0.60
Plan 2
0.40
Plan 3
0.20
Plan 4
0.00
Plan 5 0
0.02
0.04
0.06
0.08
0.1
Plan 6
Lot fraction defective, p Figure 2.141: Comparison between the probability of acceptance for the proposed tin sheets sampling plans. Table 2.79: Comparison between the probability of acceptance for the proposed tin sheets double sampling plans at different values of p.
p
Plan 1
Plan 2
Plan 3
Plan 4
Plan 5
Plan 6
0.01
0.9953
0.9731
0.9562
0.9347
0.9135
0.9506
0.02
0.9732
0.8863
0.8505
0.7845
0.7236
0.7794
0.03
0.9343
0.7833
0.7511
0.6511
0.5645
0.5696
0.04
0.8852
0.6899
0.6693
0.5477
0.4482
0.3876
0.05
0.8323
0.6109
0.6000
0.4648
0.3601
0.2533
0.06
0.7798
0.5440
0.5390
0.3957
0.2905
0.1624
0.07
0.7299
0.4863
0.4841
0.3368
0.2343
0.1035
0.08
0.6836
0.4353
0.4344
0.2863
0.1887
0.0662
0.09
0.6410
0.3898
0.3894
0.2430
0.1516
0.0426
0.1
0.6019
0.3488
0.3487
0.2059
0.1216
0.0277
Page | 142
Comparison between the AOQ for the Proposed Tin Sheets Double Sampling Plans 7.00%
AOQ
6.00% 5.00%
Plan 1
4.00%
Plan 2
3.00%
Plan 3
2.00%
Plan 4
1.00%
Plan 5
0.00% 0
0.02
0.04
0.06
0.08
0.1
Plan 6
Lot fraction defective, p Figure 2.142: Comparison between the AOQ for the proposed tin sheets sampling plans.
Table 2.80: Comparison between the AOQ for the proposed tin sheets double sampling plans at different values of p.
p
Plan 1
Plan 2
Plan 3
Plan 4
Plan 5
Plan 6
0.01
1.00%
0.97%
0.96%
0.93%
0.91%
0.95%
0.02
1.95%
1.77%
1.70%
1.57%
1.45%
1.56%
0.03
2.80%
2.35%
2.25%
1.95%
1.69%
1.71%
0.04
3.54%
2.76%
2.68%
2.19%
1.79%
1.55%
0.05
4.16%
3.05%
3.00%
2.32%
1.80%
1.27%
0.06
4.68%
3.26%
3.23%
2.37%
1.74%
0.97%
0.07
5.11%
3.40%
3.39%
2.36%
1.64%
0.72%
0.08
5.47%
3.48%
3.48%
2.29%
1.51%
0.53%
0.09
5.77%
3.51%
3.50%
2.19%
1.36%
0.38%
0.1
6.02%
3.49%
3.49%
2.06%
1.22%
0.28%
Page | 143
ATI
Comparison between the ATI for the Proposed Beans Double Sampling Plans 500,000 400,000 300,000 200,000 100,000 0
Plan 1 Plan 2 Plan 3 Plan 4 0
0.02
0.04
0.06
0.08
Lot fraction defective, p
0.1
Plan 5 Plan 6
Figure 2.143: Comparison between the ATI for the proposed tin sheets sampling plans.
Table 2.81: Comparison between the ATI for the proposed tin sheets double sampling plans at different values of p.
p
Plan 1
Plan 2
Plan 3
Plan 4
Plan 5
Plan 6
0.01
1,976
11,308
18,420
27,459
36,383
20,796
0.02
11,282
47,749
62,796
90,539
116,108
92,709
0.03
27,618
91,018
104,552 146,555 182,929 180,801
0.04
48,207
130,271 138,882 189,981 231,777 257,219
0.05
70,429
163,444 167,986 224,777 268,765 313,617
0.06
92,506
191,512 193,641 253,820 297,999 351,813
0.07
113,467 215,776 216,696 278,552 321,588 376,531
0.08
132,912 237,178 237,553 299,751 340,745 392,202
0.09
150,781 256,302 256,447 317,938 356,311 402,093
0.1
167,185 273,504 273,558 333,528 368,940 408,368
Page | 144
Comparison between the Costs of the Proposed Tin Sheets Double Sampling Plans Total Cost
150000 Plan 1 100000
Plan 2 Plan 3
50000
Plan 4
0 0
0.02
0.04
0.06
0.08
0.1
Plan 5 Plan 6
Lot fraction defective, p
Figure 2.144: Comparison between the costs of the proposed tin sheets sampling plans.
Table 2.82: Comparison between the costs of the proposed tin sheets double sampling plans at different values of p.
p
Plan 1
Plan 2
Plan 3
Plan 4
Plan 5
Plan 6
0.01
21,114
21,345
21,522
21,747
21,968
21,581
0.02
41,843
40,921
40,540
39,838
39,191
39,783
0.03
61,109
56,325
55,304
52,134
49,389
49,550
0.04
78,202
67,894
66,812
60,394
55,143
51,948
0.05
92,943
76,594
75,796
65,814
58,082
50,199
0.06
105,488
83,120
82,639
69,043
59,063
46,905
0.07
116,126
87,881
87,627
70,550
58,669
43,501
0.08
125,156
91,141
91,019
70,729
57,355
40,568
0.09
132,829
93,113
93,058
69,914
55,471
38,240
0.1
139,334
93,986
93,963
68,383
53,279
36,461
Figure 2.144 shows that Plan 6 was the clear winner when it came to minimizing the total cost of sampling and it was therefore chosen as the best double sampling plan. Page | 145
Comparison between the As-Is and Double Sampling Plans for Tin Sheets
Pa
Comparison between the Probability of Acceptance for the Tin Sheets As-Is and Double Sampling Plans 1.00 0.80 0.60 0.40 0.20 0.00
Double Sampling Plan As is Plan 0
0.02 0.04 0.06 0.08 0.1
Lot fraction defective, p Figure 2.145: Comparison between the probability of acceptance for the tin sheets as-is and double sampling plans. Table 2.83: Comparison between the probability of acceptance for the tin sheets as- is and double sampling plans at different values of p.
p
As-Is
Double Sampling
0.01
0.9044
0.9506
0.02
0.8171
0.7794
0.03
0.7374
0.5696
0.04
0.6648
0.3876
0.05
0.5987
0.2533
0.06
0.5386
0.1624
0.07
0.4840
0.1035
0.08
0.4344
0.0662
0.09
0.3894
0.0426
0.10
0.3487
0.0277
Page | 146
Comparison between the AOQ for the Tin Sheets As-Is and Double Sampling Plans 3.50% 3.00%
AOQ
2.50% 2.00% 1.50%
Double Sampling Plan
1.00%
As is Plan
0.50% 0.00% 0
0.02
0.04
0.06
0.08
0.1
Lot fraction defective, p Figure 2.146: Comparison between the AOQ for the as-is and new tin sheets sampling plans.
Table 2.84: Comparison between the AOQ for the tin sheets as- is and double sampling plans at different values of p.
Double p
As-Is
Sampling
0.01
0.90%
0.95%
0.02
1.63%
1.56%
0.03
2.21%
1.71%
0.04
2.95%
1.55%
0.05
2.99%
1.27%
0.06
2.69%
0.97%
0.07
2.42%
0.72%
0.08
2.17%
0.53%
0.09
1.95%
0.38%
0.10
1.74%
0.28%
Page | 147
ATI
Comparison between the ATI for Tin Sheets As-Is and Double Sampling Plans 450,000 400,000 350,000 300,000 250,000 200,000 150,000 100,000 50,000 0
Double Sampling Plan As is Plan
0
0.02
0.04
0.06
0.08
0.1
Lot fraction defective, p
Figure 2.147: Comparison between the ATI for the as-is and new tin sheets sampling plans.
Table 2.85: Comparison between the ATI for the tin sheets as- is and double sampling plans at different values of p
p
As-Is
Double Sampling
0.01
40,169
20,796
0.02
76,838
92,709
0.03
110,289
180,801
0.04
140,777
257,219
0.05
168,536
313,617
0.06
193,787
351,813
0.07
216,732
376,531
0.08
237,561
392,202
0.09
256,449
402,093
0.1
273,559
408,368 .
Page | 148
Total cost
Comparison between Costs of the Tin Sheets As-Is and Double Sampling Plans 80000 70000 60000 50000 40000 30000 20000 10000 0
Double sampling plan As-is plan
0
0.02
0.04
0.06
0.08
0.1
Lot fraction defective, p Figure 2.148: Comparison between the costs of the tin sheets as-is and double sampling plans.
Table 2.86: Comparison between the costs of the tin sheets as- is and double sampling plans at different values of p.
p
As-Is
Double Sampling
0.01
22,063
21,581
0.02
40,184
39,783
0.03
54,871
49,550
0.04
72,691
51,948
0.05
75,699
50,199
0.06
71,261
46,905
0.07
67,228
43,501
0.08
63,567
40,568
0.09
60,247
38,240
0.1
57,240
36,461
Page | 149
Figure 2.148 shows that the cost of the double sampling plan is less than that of the as-is plan. Therefore, the cost of the double sampling was compared with that of the new single sampling plan the one with minimum cost was chosen.
Total cost
Comparison between Costs of the Tin Sheets New Single Sampling and Double Sampling Plans 100000 0 00.02 0.04 0.06 0.080.1
Double sampling plan
Lot fraction defective, p
Table 2.87: Comparison between the costs of the tin sheets new single sampling and double Figure 2.149: Comparison between the costs of the tin sheets new single sampling and double sampling plans. sampling plans at different values of p.
p
Double Sampling
New Single Sampling
0.01
21,581
21,414
0.02
39,783
40,373
0.03
49,550
52,073
0.04
51,948
56,058
0.05
50,199
54,657
0.06
46,905
50,598
0.07
43,501
45,887
0.08
40,568
41,634
0.09
38,240
38,271
0.1
36,461
35,831
Page | 150
The double sampling plan has a lower cost as can be seen from figure 2,149 and therefore it was chosen as the best.
2. 9 Conclusion The overfilling problem was exposed and the root cause analysis indicated that the problem was with the culture in the factory rather than the process itself. By eliminating overfilling, the company can save around 68,000 KD per year. Also, the new quality control documentation will help the company track quality characteristics of their products and therefore facilitate future quality control efforts. Furthermore, by changing the timing of the PH test, defects can be detected sooner, thus minimizing cumulative costs of poor quality. Finally, the new sampling plans developed will ensure better relationships with suppliers as the chances of rejecting lots of good quality have been reduced and will also save money by reducing the overall sampling cost.
Page | 151
Page | 152
3. Cost Analysis
Page | 153
Page | 154
3.1 Introduction "Emerging technologies are revealing unprecedented opportunities for bringing new and improved products and systems into being that will be more cost effective in private and public sectors world-wide." (Fabrycky, Life –Cycle Cost and Economic Analysis) In these times of intensifying international competition, producers are searching for ways to gain sustainable competitive advantage in the marketplace. Hence, economic competitiveness is desired by corporations. Moreover, analyzing the costs of the company may help find areas of waste to be eliminated, therefore helping them generate more profit. The National Canned Food Company owns the only factory in Kuwait that fills canned food. It produces 35,869,495 cans, in twenty two different varieties, to satisfy the demand of local customers, as well as that of regional and international markets.
3.1.1 Problem Description After analyzing the costs of The National Canned Food Company, two main problems came to attention:
High costs due to overfilling: The National Canned Food Company tends to overfill a lot of their products which significantly increases their material costs.
Transportation Costs: It was noticed that transportation costs are obscenely high due to high costs of sending to certain markets with comparatively low demand.
Page | 155
3.1.2 Objectives The main objective of cost analysis is to show substantial long-term gains and cost savings by eliminating areas of “waste.” As such, the objectives are as follows: a. Finding current costs of the company. b. Find the cost of overfilling. c. Try to minimize the transportation costs. d. Find the productivity of the system.
3.1.3 Solution Approach The variable and fixed costs were found for the process. Using them, the total cost, total revenue, and total profit of the company were calculated. The breakeven point for the company, as well as the breakeven point for each of the twenty-two varieties, separately, was found. This would help the company decide whether the demand is worth covering or not for a certain product, as well as offering a clear understanding of the current situation and standing of the company regarding how and where their money is being spent. After that, the cost of overfilling was found, and the alternatives for sending demand to local or regional areas that would cost less to ship to than the international markets, therefore maintaining revenue, and at the same time lowering their transportation costs. Moreover, the company’s current productivity level and level that what would be achieved by taking the project’s analysis and suggestions into consideration were found.
Page | 156
3.2 Analysis of As-Is System: 3.2.1 System Every system has resources going into it, with the decisions being made. The system also gets resource and system outputs. And overall, there would be a value or outcome to that output. In the case of the National Canned Food Company, the system is classified as follows:
Decisions
Resource Input
National Canned
Resource Output
Food Company Labor
Labor
Material
Material
Equipment
Equipment
Energy
Energy
Capital Other
Capital
System Output
Other
Outcome
Figure 3.1: The National Canned Food Company’s system.
Page | 157
1. Suppliers The National Canned Food Company imports all their material from numerous suppliers worldwide.
Carton Suppliers:
Carton Industries Company (Kuwait).
Arabian Packaging Company (UAE).
CeaserPac (Kuwait).
Interpack Company (Kuwait).
Labels Suppliers:
British Industries Press (Kuwait).
Ms Shahid Printing Press (Kuwait).
Integrated Plastic Packaging (UAE).
Aluminum Lids Supplier:
Glue Suppliers:
Henkels Ashawa Adhesives (Saudi Arabia).
Al Hashmi Trd. (Kuwait).
Master Batch Supplier:
Express Flexi-Pack (UAE).
Calrient (Kuwait).
Mushroom Suppliers:
Welton International Group Ltd (China).
Xiamen Continent Economic Development Ltd (China).
Xiamen Gulong Imp & Exp Co. (China).
Xiamen Huilon Imp & Export Trading Co. (China).
Page | 158
Frozen Sweet Corn Supplier:
Sweet Kernal Corn Supplier:
Intralox Inc. (The Netherlands).
Carnaid Metalbox Engineering (England).
Soudronic AG (Switzerland).
Electrolytic Tinplate Suppliers:
Containers Printers (Singapore).
Pacmetal Services (Australia).
Mitsui & Co Ltd (Japan).
Peter Cremer (Germany).
Al Rajhi Co. for Ind. & Trading (KSA).
Soudronic Wire Supplier:
Gulf Closures W.L.L (Bahrain).
Etimelt 103 Supplier:
Holden Surface Coatings Ltd. (England).
White Wing Lok Closure Supplier:
Asia Countries W.L.L (Kuwait).
Lacquer and Thinner Supplier:
Lamex Foods (The Netherlands).
Spare Parts Suppliers:
Mirelite Foreign Trade (Hungary).
National Adhesives Limited (KSA).
Seaming Chucks and Seaming Rolls Supplier:
T.A.J Engineers Ltd. (England).
Page | 159
Can Ends Suppliers:
A.C.P International (Italy).
Mivisa Envases S.A. (Spain).
Impress Metal Packaging Capolo SPA (Italy).
Al Rajhi Co. for Ind. & Trading (KSA).
Flavors and Ingredients Suppliers:
Ali Abdulkarim Trading Co. (Oman).
Tuncsan Salca Konserve Gisa San (Turkey).
Proguimac Color (Spain).
Crestar UK Ltd. (UK).
Food Specialties (UAE).
Leverbrook Ltd (England).
Aralco (France).
Beans and Peas Suppliers:
Pars Ram Brothers (Australia).
Muelle SA (Peru).
Midgulf International (Jordan).
Rizhao Sunway International (China).
Lamex Foods (The Netherlands).
P.S. International Ltd (USA).
Pars Ram Brothers (Australia).
Peters Commodities Ltd (Australia).
The Great Canadian Bean (Canada).
KBC Trading and Processing Co. (USA).
Export Packets Company Ltd (Canada).
Anny Frantzen (Denmark).
Page | 160
2. Customers
Local supermarkets (e.g. Co-ops).
Whole sale stores (e.g. Sultan Centers).
Small stores.
Regional and international markets.
3. Missions and Goals of The National Canned Food Company
Provide the local, regional, and international markets with their demand for canned food, maintaining high quality standards and reasonable prices.
Satisfy all of their customers’ demand, without any delays.
4. Resources
Labor Maintenance, engineers, laborers, machine operators, forklift operators, quality control, assistant operators, supervisors, technicians, sales person, accountant, secretary, data entry workers, messenger, invoice collector, senior accountant, assistant general manager, store keeper, assistant store keeper, watchman, transportation person.
Materials Baked beans, black eye beans, broad beans, chick peas, chick peas 10mm, chick peas with chili, green peas, hummus tehinah - chick peas 7mm, hummus tehinah with garlic, lima beans, mixed
vegetables, mushroom
pieces and
stems, whole
mushrooms, peas and carrots, peeled fava beans with chili, red kidney beans, red kidney beans with chili, sweet corn, fava beans, white beans.
Page | 161
Equipments Container and Product Technology, Electric Control Cabinet, Line Control Equipment, Labeler, Case Packer, Treadle Operated Case Stapler,
Hand Case Taper,
Crate Loader,
Crate Un-loader, Crate Frasers Horizontal Retorts, Associated Equipment for Retorts, MetaMatic Slat Chain Conveyor, MetaMatic Filled Can Washer, MetaMatic Gravity Changepart Twist, MetaMatic Slat Chain Conveyor, Incline Filled Can Magnetic Elevator, MetaMatic Gravity Roller Conveyor, Pea and Bean Filler, Cannery Seamer, MetaMatic No.1 De-palletizer, MetaMatic Vertical Magnetic Elevator and Change Parts Twist, MetaMatic Empty Can Cable Conveyor, MetaMatic Empty Can Rinse and Change Part Twist, Can Opening System, 2000 L Storage Tank, 900 L open Top Tank, 3000L Steam Jacketed Mixing Tanks,
Alpha Laval Plate Heat Exchanger, Ancillary
Equipment, C.I.P. Plant, Hot Water Rotary Blancher, Vibrator De-Watering Elevator,
Screen,
Inspection
Buffer Storage Hopper,
Gooseneck Elevator,
Conveyor,
Gooseneck
Intake Sack Tip Hopper,
Pneumatic Separator with Vibrator
Feeder, Belt Distribution Conveyor, Soaking Tanks, Flumes, Suction Tank and Buffer Storage Hopper, Vibrator De-Watering Screen.
Energy Electricity, petrol, water.
Capital Land, building, capital (money).
Other maintenance, insurance, marketing, transportation.
Page | 162
5. Output
Number of cans.
Revenue from sales.
6. Outcome
Customer satisfaction.
Profit.
Assure canned food availability.
7. Performance Measures Performance measures are set to have some standards to adhere to. Meeting their performance measures allows The National Canned Food Company to fulfill their objectives.
Utilization of machines (number or busy machines per hour).
Can production rate.
Can filling rate.
Amount of waste.
Number of defects.
Machine breakdowns.
8. Decisions The National Canned Food Company Should Consider What should the working hours of the workers in the office be? What should the working hours of the workers in the factory be? What are the operating hours of the factory? How many workers should the factory have? How many office workers should they have? Page | 163
How many hours is one shift? How many shifts are there during the day? What are the working hours of the workers in the factory? What should the salaries/wages of all labor Involved? What should the price of the products be? What variety of products should the company offer? How many of the products should they produce? What quality standards of production should the company maintain? What facility layout is appropriate for the factory? Delivery Decisions. Storage Decisions.
3.2.2 Productivity Indices The productivity indices used to calculate The National Canned Food Company’s productivity are the inputs and outputs of the company explained in the previous section (labor, material, equipment, energy, other). The numerical values for those inputs and outputs may be obtained by classifying the costs as direct costs, indirect costs, technical overheads, company overheads, and marketing overheads. And from that, the total cost and total revenue of The National Canned Food Company was calculated.
1. Direct Cost A direct cost is a cost that is directly attributable to the manufacture of a product (or provision of a service). A good example of a direct cost is the cost of the materials needed to make a product. The usage of the materials is directly related to the manufacture of the product. Direct costs are very often variable costs and vice-versa, but the two are not synonymous. There are three types of direct cost:
Direct materials,
Direct labour, and
Direct expenses (mainly equipment).
Page | 164
Direct Labor Costs The direct labor costs include most of the labor in the can filling plant. They include all of the machine operators and the forklift operators, since those laborers are necessary for the production line.
Table 3.2: Direct labor costs.
Designation
Salary (KD/month)
Machine Operator Machine Operator Machine Operator Machine Operator Machine Operator Machine Operator Machine Operator Machine Operator Machine Operator Machine Operator Machine Operator Forklift Operator Forklift Operator Forklift Operator
248 195 150 135 225 150 180 113 135 135 120 105 105 165 Total
2160
Page | 165
Direct Material Cost
(1) Can Making Direct Material Cost: The National Canned Food Company produces the cans to be filled. Each can requires all of the materials listed in table 3.2. Also given are the cost of each of the materials individually, the quantity they require of each material annually, and their annual production. To obtain the direct cost of each can, certain calculations were used to convert the indiscrete units to cost/unit.
Page | 166
Table 3.3: Can making costs.
Order Quantity Per Year
Usage per year
Usage Quantity * Per can
Cost/can**
Cost*** (KD/Year)
Description
Unit
Cost (KD/unit)
Labels
PCS
0.0048
35,869,496
35,869,496
1
0.0048
172,173.58
Copper Wires
K.G
3.783
85,000
35,869,496
0.00237
0.0089646
321,555.00
Standard Lids
PCS
0.009
48,851,442
35,869,496
1.36192
0.0122573
439,662.98
Easy Open Lids
PCS
0.017
17,283,814
35,869,496
0.48185
0.0081915
293,824.84
Tin Sheets
PCS
0.56
1,303,796
35,869,496
0.03635
0.0203551
730,125.76
Cartons
PCS
0.018
2,880,000
35,869,496
0.08029
0.0014452
51,840.00
Shrink Film
PCS
0.96
28,234
35,869,496
0.00079
0.0007556
27,104.64
Glue
K.G
1.5
27,002
35,869,496
0.00075
0.0011292
40,503.00
Lacquer
K.G
1.2
24,714
35,869,496
0.00069
0.0008268
29,656.80
*Quantity per unit = Quantity per year / Annual Production **Cost/can = Quantity per unit * cost of material (KD/unit) ***Cost (KD/year) = cost (KD/unit) * Quantity per year
Page | 167
(2) Can Filling Direct Material Cost: (a) Beans Direct Cost The National Canned Food Company produces different types of products, including water, vinegar, ketchup and sausages which will not be included in this study since they are produced in a different line. The products presented in the table below, are the ones being considered. They are all considered to be direct costs. Given the cost in KD/ton and the quantity in kg/year, the cost in KD/year was calculated.
Table 3.4: Cost of direct material cost for the beans.
Description Baked Beans Black Eye Beans Broad Beans Chick Peas Chick Peas 10mm Chick Peas with Chili Fava Beans Fava Beans with Chili Green Peas Hummus Tehinah Hummus Tehinah with Garlic Lima Beans Mixed Vegetables Mushroom Pieces and Stems Whole Mushrooms Peas and Carrots Peeled Fava Beans with Chili Red Kidney Beans Red Kidney Beans with Chili Sweet Corn Fava Beans White Beans TOTAL
Production Cans/Year 3,489,494 494,928 4,949,942 6,581,088 856,454 46,080 5,284,656 66,960 7,272,720 3,925,008 27,014 94,464 351,936 182,534 234,864 51,264 230,918 772,934 21,600 631,238 174,027 129,370 35,869,496
Cost KD/year 83,107.30 14,005.60 116,117.50 126,880.54 77,293.75 888.40 74,886.58 948.86 52,628.31 29,292.47 201.61 23,661.92 32,008.32 35,191.80 43,989.75 963.37 4,632.81 48,588.55 1,357.83 40,057.24 3,491.42 26,165.11 836,359.04
Page | 168
(b) Additives Direct Cost: Each can is filled with the raw materials and certain additives. The exact ingredients and recipe of each product were considered confidential by The National Canned Food Company. Given the cost of their annual order of additives and the ingredients label on each can, the cost of each product with its respective additives were obtained, as is shown in table 3.6. Since ratios were used to obtain the relative costs, the following example on the broad beans will demonstrate how the costs were obtained in table 3.4. To make broad beans, only two additives were used; EDTA and citric acid: Annual Production of broad beans = 4,949,942 cans/year Annual Cost of EDTA = 2,400 KD/year Productions and annual production rates of different variety that include EDTA: Table 3.5: Sample of additive calculation for broad beans.
Description Black Eye Beans Broad Beans Chick Peas Chick Peas 10mm Chick Peas with Chili Fava Beans Fava Beans with Chili Lima Beans Peeled Fava Beans with Chili Foul Medames White Beans TOTAL
Annual Production 494,928 4,949,942 6,581,088 856,454 46,080 5,284,656 66,960 94,464 230,918 174,027 129,370 18,908,887
EDTA* KD/year 62.82 628.27 835.30 108.70 5.85 670.75 8.50 11.99 29.31 22.09 16.42 2,400.00
EDTA cost = (Annual cost of EDTA / Total can production using EDTA) * Broad bean annual production = (2400/ 18,908,887)*4,949,942 = 628.27 KD/year (EDTA use for broad beans)
The same procedure was done to obtain the figures for the citric acid. Page | 169
Table 3.5: Annual cost of additives.
Description
Unit
Cost per
Order Quantity
Unit
(Unit/year)
Cost (KD/year)
Given Tomato Paste
K.G
0.650
24,000
15,600.000
Lemon Juice
Ltr
2.900
6,000
17,400.000
Green Color
K.G
5.500
350
1,925.000
EDTA
K.G
1.000
2,400
2,400.000
Citric Acid
K.G
0.868
23,500
20,398.000
Camon Powder
K.G
1.500
1,950
2,925.000
Chick Peas
K.G
0.650
5,205
3,383.250
Spices
K.G
2.000
600
1,200.000
Whole Red Chili
K.G
1.650
819
1,351.350
Onion Powder
K.G
2.250
470
1,057.500
Powdered Red
K.G
0.950
624
592.800
Powder
Chili Total
68,232.900
Page | 170
Page | 171
Table 3.6: Direct material cost of additives
Page | 172
Table 3.6: Direct material cost of additives (continued).
(3) Total Direct Cost of Materials: The cost of materials is the total cost of both the beans and the additives of each product. The cost of the beans, shown in Table 3.3, and the cost of the total additives, from Tables 3.5 and 3.6, is added to give us the total cost, in KD, for each type. Then the following equation was used to give us the direct cost in KD/unit: Direct cost = Total cost (KD/Year) / Production (Units/Year) Table 3.7: Direct costs of materials (beans and additives).
Description
Annual Production Cans/year
Cost of Beans ( KD/year)
Total Cost
Direct Cost* (KD/unit)
83,107.3 14,005.6 116,117.5 126,880.54 77,293.75 888.4 74,886.58 948.86 52,628.31 29,292.47
Total Additive Cost (KD/year) 16,674.33 62.82 7,274.02 835.3 108.7 5.85 7,765.89 416.53 1,911.53 5,269.69
Baked Beans Black Eye Beans Broad Beans Chick Peas Chick Peas 10mm Chick Peas with Chili Fava Beans Fava Beans with Chili Green Peas Hummus Tahineh – Chick Peas 7mm HummusTahineh with Garlic Lima Beans Mixed Vegetables Mushroom Pieces and Stems Whole Mushrooms Peas and Carrots Peeled Fava Beans with Chili Red Kidney Beans Red Kidney Beans with Chili Sweet Corn Foul Medames White Beans TOTAL
34,89,494 494,928 4,949,942 6,581,088 856,454 46,080 5,284,656 66,960 7,272,720 3,925,008
99,781.63 14,068.42 123391.52 127715.84 77402.45 894.25 82,652.47 1365.39 54,539.84 34,562.16
0.0286 0.0284 0.0249 0.0194 0.0904 0.0194 0.0156 0.0204 0.0075 0.0088
27,014
201.61
36.27
237.88
0.0088
94,464 351,936 182,534
23,661.92 32,008.32 35,191.8
11.99 472.51 245.07
23,673.91 32,480.83 35,436.87
0.2506 0.0923 0.1941
234,864 51,264 230,918
43,989.75 963.37 4,632.81
0 13.47 15,481.58
43,989.75 976.84 20,114.39
0.1873 0.0191 0.0871
772,934 21,600
48,588.55 1,357.83
0 696.01
48,588.55 2,053.84
0.0629 0.0951
631,238 174,026 129,369 35,869,495
40,057.24 3,491.42 26,165.11 836,359.04
0 10,898.92 16.42
40,057.24 14,390.34 26,181.53 904,555.9
0.0635 0.0827 0.2024 0.0252
Page | 173
* Direct cost = Total cost (KD/Year) / Production (Units/Year) Total Direct Material Cost: The total material direct cost is the sum of the unit direct cost of each can, bean and additive, as presented in Table 3.8 below. The Total Direct Cost in KD
per
year
was
also
obtained
as shown
the
Table
8
below.
* Total Direct Cost (KD/year) = Total Material Direct Cost * Production (KD/unit)
(KD/Year)
Page | 174
Table 3.8: Total direct material costs.
Total
Total Direct
Material
Cost
Can
Direct Cost *
KD/year
KD/Year
KD/can
KD/unit
0.028594867
99,781.63
0.058725
0.084892
296,230.1586
494,928
0.028425185
14,068.42
0.058725
0.087464
43,288.38259
Broad Beans
4,949,942.4
0.02492787
123,391.52
0.058725
0.082686
409,290.9373
Chick Peas
6,581,088
0.019406493
127,715.84
0.058725
0.078038
513,574.9453
856,454.4
0.090375448
77,402.45
0.058725
0.149229
127,807.8337
46,080
0.019406467
894.25
0.058725
0.08274
3,812.6592
5,284,656
0.015640085
82,652.47
0.058725
0.073366
387,714.0721
66,960
0.020391129
1,365.39
0.058725
0.125798
8,423.43408
7,272,720
0.007499235
54,539.84
0.058725
0.066094
480,683.1557
3,925,008
0.008805628
34,562.16
0.058725
0.066766
262,057.0841
27,014.4
0.008805674
237.88
0.058725
0.150086
4,054.483238
Description
Baked Beans Black Eye Beans
Chick Peas 10mm Chick Peas with Chili Fava Beans Fava Beans with Chili Green Peas
Direct Cost
Direct Cost
Beans +
Beans +
Additives
Additives
Unit/Year
KD/unit
3,489,494.4
Annual Production
Direct Cost
Hummus Tahineh Chick Peas 7mm Hummus Tahineh with Garlic
Page | 175
Table 3.8: Total direct material Costs (continued).
Description
Lima Beans
Total Material Direct Cost *
Total Direct Cost
Direct Cost
Direct Cost
Direct Cost
Beans + Additives
Beans + Additives
Can
Unit/Year
KD/unit
KD/Year
KD/can
KD/unit
94,464
0.250613038
23,673.91
0.058725
0.311521
29,427.51974
351,936
0.092291866
32,480.83
0.058725
0.156114
54,942.1367
Annual Production
KD/year
Mixed Vegetables Mushroom Pieces and Stems Peeled Fava Beans with Chili Red Kidney Beans Red Kidney Beans with Chili
182,534.4
0.194138036
35,436.87
0.058725
0.263937
48,177.58193
230,918.400
0.087
20,114.390
0.059
0.146
33,718.705
772,934.400
0.063
48,588.550
0.059
0.122
93,979.548
21,600.000
0.095
2053.840
0.059
0.529
11,419.099
Sweet Corn
631,238.400
0.063
40,057.240
0.059
0.122
77,126.601
Foul Medames
174,026.900
0.083
14,390.340
0.059
0.164
28,578.698
White Beans
129,369.600
0.202
26,181.530
0.059
0.263
33,980.607
TOTAL
3,011,006.187
Page | 176
Equipment Direct Cost Since the can filling production line is in series, and all the equipment are vital and required to produce each unit of product, all the machines are considered to be direct costs. All the equipment was bought in 1984 and have not been replaced since. The lifespan of all machines is supposedly ten years. However, The National Canned Food Company still uses the same machines, even though it has been 25 years.
Page | 177
Table 3.9: Direct equipment costs.
Process
Machine
Description
Container and Product
Metal box available to
Technology
undertake tests on the
Cost (KWD) 10,226.4
compatibility of container and product Electrical Controls: Electric Control Cabinet
Dry product preparation
8,153.72
Soaking, blanching and product feed Filling, closing, and can handling Crate unloading, can drying , labeling, and case packing Line Control Equipment
To regulate flow of cans
1,329.43
and product Labeling and Case Packing Labeler
Labels the cans
3,573.51
Case Packer
To collate cans in 3*4*2
6,274.92
configuration Treadle Operated Case
797.66
Stapler Hand Case Taper
5.32
Page | 178
Table 3.9: Direct equipment costs (continued).
Process
Machine
Description
Cost (KWD)
Processing Crate Loader
Chain in-feed conveyor
3,589.47
Crate Un-loader
Discharge conveyor
6,593.98
Crate Frasers Horizontal Retorts
Steam retort
34,219.58
Associated Equipment for Retorts
Flat top trucks and crates with
7,147.026
loose bottoms Transporter trucks Filled Can Handling MetaMatic Slat Chain Conveyor
Conveys cans from seamed
1,239.03
discharge to filled can washer MetaMatic Filled Can Washer
Removes any slight traces of
3031.1
sauce or brine adhering to the can MetaMatic Gravity Changepart
From crate un-loader to slat chain
Twist
conveyor
MetaMatic Slat Chain Conveyor
Slat chain conveyor with fixed
204.94
1,239.03
speed drive MetaMatic Alpine Conveyor
Elevates cans to labeler in-feed
MetaMatic Gravity Changepart
Conveys cans to and from the
Twist
labeler and case packer
Incline Filled Can Magnetic
Elevates filled cans to filled can
Elevator
cable conveyor
MetaMatic Gravity Roller Conveyor
For filled case conveying
4,785.96 638.13
3,759.63
265.87
Page | 179
Process
Machine
Description
Cost (KWD)
Filling and Closing Table 3.9: Direct equipment costs (Continued).
Pea and Bean Filler
Solids and liquid twin head filler
29,247.50
for peas and beans Consists of guarding, level control, combined support for level control and/or mixer, duty Cannery Seamer
Closing cans
MetaMatic Vertical Magnetic
Discharge with gravity transfer to
Elevator and Change Parts
cable conveyor
25,331.20
Empty Can Handling 3,456.52
Twist MetaMatic Empty Can Cable
Conveys cans from elevator to
Conveyor
filling area
MetaMatic Empty Can Rinse
Pre-wash can prior to filling
2,233.45
1,967.56
and Change Part Twist Brine & Sauce Prep. Can Opening System
Opens tomato paste cans
439.74
2000 L Storage Tank
Stores vegetable oil
2,197.86
900 L open Top Tank
Premixes sugar, seasoning, etc.
1,475.87
3000L Steam Jacketed
Preheat sauce or brine
12,741.28
Sauce and brine heater
3,929.80
Mixing Tanks Alpha Laval Plate Heat Exchanger Ancillary Equipment
Control panel suitable for
10,770.44
temperature control, etc. C.I.P. Plant
Cleans brine and sauce
5,158.20
preparation equipment
Page | 180
(1) Depreciation:
The National Canned Food Company use the straight line method to depreciate their equipment.
Salvage value is assumed to be zero. Table 3.10: Depreciation of machines.
Machine
Life
Cost
Depreciated
Span
(KWD)
Value Per Year
(n) Container and Product Technology
25
10,226.4
409.1
Electric Control Cabinet
25
8,153.7
326.1
Line Control Equipment
25
1,329.4
53.2
Labeler
25
3,573.5
142.9
Case Packer
25
6,274.9
251.0
Treadle Operated Case Stapler
25
797.7
31.9
Hand Case Taper
25
5.3
0.2
Crate Loader
25
3,589.5
143.6
Crate Un-loader
25
6,594.0
263.8
Crate Frasers Horizontal Retorts
25
34,219.6
1,368.8
Associated Equipment for Retorts
25
7,147.0
285.9
MetaMatic Slat Chain Conveyor
25
1,239.0
49.6
MetaMatic Filled Can Washer
25
3,031.1
121.2
MetaMatic Gravity Changepart Twist
25
204.9
8.2
MetaMatic Slat Chain Conveyor
25
1,239.0
49.6
MetaMatic Alpine Conveyor
25
4,786.0
191.4
MetaMatic Gravity Changepart Twist
25
638.1
25.5
Incline Filled Can Magnetic Elevator
25
3,759.6
150.4
MetaMatic Gravity Roller Conveyor
25
265.9
10.6
Pea and Bean Filler
25
29,247.5
1,169.9
Cannery Seamer
25
25,331.2
1,013.2
MetaMatic No.1 De-palletizer
25
7,976.6
319.1
Page | 181
Table 3.10: Depreciation of machines (continued).
Machine
Life Spa n (n)
Cost (KWD)
Depreciate d Value Per Year
MetaMatic Vertical Magnetic Elevator and Change Parts Twist
25
3,456.50
138.3
MetaMatic Empty Can Cable Conveyor MetaMatic Empty Can Rinse and Change Part Twist
25 25
2,233.40 1,967.60
89.3 78.7
Can Opening System 2000 L Storage Tank 900 L open Top Tank 3000L Steam Jacketed Mixing Tanks
25 25 25 25
17.6 87.9 59 509.7
Alpha Laval Plate Heat Exchanger Ancillary Equipment
25 25
Vibrator De-Watering Screen Inspection Conveyor Gooseneck Elevator Buffer Storage Hopper Intake Sack Tip Hopper Gooseneck Elevator Pneumatic Separator with Vibrator Feeder Gooseneck Elevator Belt Distribution Conveyor Suction Tank and Buffer Storage Hopper Vibrator De-Watering Screen Forklift TOTAL
25 25 25 25 25 25 25
439.7 2,197.90 1,475.90 12,741.3 0 3,929.80 10,770.4 0 1,522.10 5,199.10 1,527.40 4,254.20 1,063.50 1,442.70 1,995.40
25 25 25 25 25
1,662.80 5,133.20 2,083.30 1,522.10 18,000
66.5 205.3 83.3 60.9 720 10,469.90
157.2 430.8 60.9 208 61.1 170.2 42.5 57.7 79.8
Page | 182
2. Indirect Costs Indirect costs are those costs that are needed but not essential to produce each part. In the case of the National Canned Food Company, all of the indirect costs are labor costs. Indirect costs are very often variable costs. There are three types of indirect cost:
Indirect materials,
Indirect labour, and
Indirect expenses (mainly equipment).
The indirect costs of The National Canned Food Company are the following: a) Indirect Material: (none) b)
Indirect Labor: Table 3.11: Indirect labor costs.
Designation
Salary (KD/month)
Quality Controller
375
Quality Controller
270
Quality Controller
270
Quality Controller
255
Assistant Operator
128
Assistant Operator
105
Assistant Operator
173
Assistant Operator
98
Assistant Operator
98
Assistant Operator
98
Assistant Operator
180
Assistant Operator
90
Assistant Operator
90
Assistant Operator
98
Total
2,325 Page | 183
Workers may have the same designation with different salaries based on their work experiences, how hard working they are, and their nationality.
Office workers have no overtime.
Can plant workers are requested to stay overtime depending on the work requirement.
A maximum of 4 overtime hours are allowed per day.
On average, each worker in the National Canned Food Company works 40-50 overtime hours per month.
The overtime for plant workers is as follows: Normal days per hour = Total salary / 30 / 8*1.25 Fridays per hour = Total salary / 30 / 8*1.50 Holidays per hour = Total salary / 30 / 8*1.75
The total overtime cost is 1,750 KD per month.
c) Indirect Equipment: (none)
Page | 184
3. Overheads Overheads are those costs which are incurred in the running of the business and which are not directly associated with a specific job. Overhead costs are always fixed. There are three types of overheads:
Technical Overheads Technical or factory overheads are any expenses related to production but are not included in every unit. Table 3.12: Technical overheads costs.
Designation
Salary (KD/month)
Spare Parts
5,000
Equipment Maintenance
1,458.33
Supervisor
525
Technical
210
Laborer
98
Laborer
180
Laborer
180
Laborer
180
Laborer
180
Laborer
135
Laborer
90
Laborer
150
Laborer
90
Laborer
75
Laborer
75
Laborer
90
Laborer
105
Total
8,821.33
Page | 185
Company Overheads Company overheads are, as the name implies, those expenses that are not related to manufacturing the product but rather related to management and office.
Table 3.13: Company overheads costs.
Designation
Salary (KD/month)
Export and Import Accountant Data Entry 1 Secretary Messenger Invoice Collector Senior Accountant Assistant General Manager Data Entry Store Keeper Assistant Store Keeper Store Keeper Watchman Transportation Insurance Utilities: Water Utilities: Petrol Utilities: Electricity Land Total
451 442 400 255 527 527 680 1,275 170 300 180 105 135 14,880 833 600 2,450 700 500 25,409
Marketing Overheads The Marketing costs are 12,000 KD/year. They mainly use this amount for designs for the labels and posters.
The National
Canned Food Company doesn't advertise in Kuwait. Every year they attend a marketing exhibition in Dubai.
Page | 186
4) Modeling Costs Overview: a) Materials: Direct Materials Cost = 3,011,006.187 KD/year. Indirect Material Cost = 0 KD/year. Total Material Cost = 3,011,006.187 KD/year. b) Labors: Direct Labors Cost = 2,160 KD/year. Indirect Labors Cost = 2,325 KD/year. Total Labors Cost = 4,485 KD/year. c) Equipment: Direct Machine Cost = 10,469.9 KD/year. Indirect Machine Cost = 0 KD/year. Total Machine Cost = 10,469.9 KD/year. Total Direct Cost = 3,013,166.187 KD/year. Total Indirect Cost = 2,325 KD/year.
d) Overheads: Technical Overhead Cost = 8,821.33 KD/year. Company Overhead Cost = 25,409 KD/year. Marketing Overhead Cost = 12,000 KD/year.
Total Overhead Cost = 46,230.33 KD/year.
Page | 187
5. Variable Cost Variable costs are the costs that change according to the production rate. For The National Canned Food Company, the only variable costs are the material costs, utilities, and overtime since these are the costs that change with the production rate. Hence, the total material direct cost + utility cost is the unit variable cost. Multiplying the unit variable cost by the annual production rate will result in the variable cost in KD/year. Table 3.14: Variable costs.
Total Description
Annual
Material
Production
Direct Cost
Unit
Variable
Variable
Cost
Cost
Unit/Year
KD/unit
(KD/unit)
KD/year
Baked Beans
3,489,494
0.0873
0.0873
304,632.83
Black Eye Beans
494,928
0.0872
0.0872
43,157.72
Broad Beans
4,949,942
0.0837
0.0837
414,310.15
Chick Peas
6,581,088
0.0781
0.0781
513,982.97
Chick Peas 10mm
856,454
0.1491
0.1491
127,697.29
Chick Peas with Chili
46,080
0.0781
0.0781
3,598.85
Fava Beans
5284656
0.0744
0.0744
393,178.41
Fava Beans with Chili
66,960
0.0791
0.0791
5,296.54
Green Peas
7,272,720
0.0662
0.0662
481,454.06
Hummus Tahineh - Chick Peas 7mm
3,925,008
0.0675
0.0675
264,938.04
Hummus Tahineh with Garlic
27,014
0.0675
0.0675
1,823.45
Lima Beans
94,464
0.3093
0.3093
29,217.72
Mixed Vegetables
351,936
0.151
0.151
53,142.34
Mushroom Pieces with Stems
182,534
0.2529
0.2529
46,162.85
Whole Mushrooms
234,864
0.246
0.246
57,776.54
Peas and Carrots
51,264
0.0778
0.0778
3,988.34
Peeled Fava Beans with Chili
230,918
0.1458
0.1458
33,667.84
Red Kidney Beans
772,934
0.1216
0.1216
93,988.77
Page | 188
Table 3.14: Variable costs (continued).
Description
Annual Production
Total Material Direct Cost
Unit Variable Cost
Variable Cost
Unit/Year
KD/unit
(KD/unit)
KD/year
Red Kidney Beans with Chili
21,600
0.1538
0.1538
3,322.08
Sweet Corn
631,238
0.1222
0.1222
77,137.28
Foul Medames
174,026
0.1414
0.1414
24,607.28
White Beans
129,369
0.2611
0.2611
33,778.25
TOTAL
35869496
3,010,859
Variable Cost KD/month
Variable Cost
Variable Cost
KD/year
KD/unit
Utility: Water
600
7,200
0.000200728
Utility: Electricity
700
8,400
0.000234182
2,450
29,400
0.000819638
Utilities: Petrol TOTAL
Total Overtime Cost TOTAL VARIABLE COST
45,000
0.001254548
Variable Cost KD/month
Variable Cost
Variable Cost
KD/year
KD/unit
1,750
21,000
3,076,859.58
0.000585456 0.001840004 (Utilities +OT)
Page | 189
6. Fixed Costs Fixed costs are those costs that do not vary or change with the production rate. Therefore, the fixed cost in the case of the National Canned Food Company would be the sum of the overheads and the direct labor and equipment costs. Total Overheads = Technical Overhead + Company Overhead + Marketing Overhead = (8,821.33*12) + (21,659*12) + 12,000 = 105,855.96 + 259,908 + 12,000 = 377,763.96 KD/year Total Equipment Cost = 10,469.9 KD/Year Total Labor Costs = Direct Labor + Indirect Labor = (2160*12) + (2325*12) = 25,920 + 27,900 = 53,820 KD/year
Total Fixed Cost = Total Overheads + Total Equipment Costs + Total Labor Costs = 377,763.96 + 10469.9 + 53,820 = 442,053.86 KD/year
7. Total Cost The total cost is the sum of the variable and fixed cost. Total Cost = Variable Cost + Fixed Cost = 3,076,859.58+ 442,053.86 = 3,518,913.44 KD/year
Page | 190
8. Total Revenue: The total revenue is how much money the company makes from selling their products. The selling price is how much the product is being sold for, and the total revenue per year is obtained from multiplying the selling price by how much is being produced every year of each product. Table 3.15: Total revenue.
Description
Baked Beans
Annual
Selling
Production
Price
Cans/Year
KD/unit
Total Revenue; SP*X KD/Year
3,489,494
0.135
471,081.74
494,928
0.130
64,340.64
Broad Beans
4,949,942
0.120
593,993.09
Chick Peas
6,581,088
0.120
789,730.56
856,454
0.170
145,597.25
46,080
0.135
6,220.80
5,284,656
0.110
581,312.16
66,960
0.120
8,035.20
Green Peas
7,272,720
0.085
618,181.20
Hummus Tahineh - Chick
3,925,008
0.110
431,750.88
Hummus Tahineh with Garlic
27,014
0.120
3,241.73
Lima Beans
94,464
0.330
31,173.12
Mixed Vegetables
351,936
0.185
65,108.16
Mushroom Pieces with
182,534
0.300
54,760.32
234,864
0.300
70,459.20
51,264
0.130
6,664.32
Peeled Fava Beans with Chili
230,918
0.170
39,256.13
Red Kidney Beans
772,934
0.155
119,563.29
21,600
0.170
3,665.25
Sweet Corn
631,238
0.165
104,154.34
Foul Medames
174,027
0.175
30,454.71
White Beans
129,370
0.280
36,223.49
35,869,496
3.714
4,274,967.57
Black Eye Beans
Chick Peas 10mm Chick Peas with Chili Fava Beans Fava Beans with Chili
Peas 7mm
Stems Whole Mushrooms Peas and Carrots
Red Kidney Beans with Chili
TOTAL
Page | 191
9. Total Profit Total profit = Total Revenue – Total Cost = 4,274,967.57- 3,519,056.42 = 755,911.15 KD/Year
Profit Margin = Profit / Revenue = 755,911.15 / 4,323,882.3 = 17.48 %
The following table, Table 3.16, shows how the allocation of the cost, revenues and profits are for each of the products individually.
Page | 192
Table 3.16: Total profit.
Annual Description
Production
Unit Variable
Fixed Cost
Total Cost
Cost
Total Revenue
Total Profit
Cans/Year
(KD/unit)
KD/year
KD/Year
KD/Year
KD/Year
Baked Beans
3,489,494
0.089
43,004.348
354,057.893
471,081.744
117,023.851
Black Eye Beans
494,928
0.089
6,099.468
50,167.859
64,340.640
14,172.781
Broad Beans
4,949,942
0.086
61,002.836
484,420.928
593,993.088
109,572.160
Chick Peas
6,581,088
0.080
81,104.997
607,197.198
789,730.560
182,533.362
Chick Peas 10mm
856,454
0.151
10,554.896
139,828.126
145,597.248
5,769.122
46,080
0.080
567.888
4,251.523
6,220.800
1,969.277
5,284,656
0.076
65,127.834
468,030.029
581,312.160
113,282.131
66,960
0.081
825.212
6,244.954
8,035.200
1,790.246
7,272,720
0.068
89,628.635
584,464.532
618,181.200
33,716.668
3,925,008
0.069
48,371.601
320,531.671
431,750.880
111,219.209
27,014
0.069
332.919
2,206.098
3,241.728
1,035.630
Lima Beans
94,464
0.311
1,164.170
30,555.699
31,173.120
617.421
Mixed Vegetables
351,936
0.153
4,337.242
58,127.141
65,108.160
6,981.019
Chick Peas with Chili Fava Beans Fava Beans with Chili Green Peas Hummus Tahineh Chick Peas 7mm Hummus Tahineh with Garlic
Page | 193
Table 3.16: Total profit (continued).
Description
Annual Production
Unit Variable Cost
Fixed Cost
Total Cost
Total Revenue
Total Profit
Cans/Year
(KD/unit)
KD/year
KD/Year
KD/Year
KD/Year
Mushroom Pieces and Stems
182,534
0.255
2,249.54
48,748.35
54,760.32
6,011.97
Whole Mushroom
234,864
0.248
2,894.45
61,103.15
70,459.20
9,356.05
Peas and Carrots
51,264
0.08
631.775
4,714.44
6,664.32
1,949.88
230,918
0.148
2,845.82
36,938.62
39,256.13
2,317.51
772,934
0.123
9,525.60
104,936.63
119,563.29
14,626.67
21,600
0.156
266.197
3,628.02
3,665.25
37.229
Sweet Corn
631,238
0.124
7,779.35
86,078.16
104,154.34
18,076.18
Foul Medames
174,027
0.143
2,144.69
27,072.30
30,454.71
3,382.41
White Beans
129,370
0.263
1,594.34
35,610.78
36,223.49
612.708
TOTAL
35,869,496
2.942
442,053.80
3,518,914.09
4,274,967.57
756,053.47
Peeled Fava Beans with Chili Red Kidney Beans Red Kidney Beans with Chili
Page | 194
10. Productivity Analysis Results All the previously collected data were used to calculate the productivity of the National Canned Food Company. Total Productivity = Total Output / Total Input = Total Revenue /Total Cost = 42,749,67.57 / 3,518,913.44 = 1.214 > 1
Since the total productivity is greater than 1, it means that The National Canned Food Company is productive.
11. Break Even Point The breakeven point is the point that the company covers its losses and from then on starts making profit. This point is when the total profit is equal to zero. To graphically show the breakeven point, the total cost is plotted against total revenue. The point of intersection is the breakeven point. Figure 3.2 shows the breakeven point for the company as a whole. Appendix V contains the breakeven points for each product on its own. These can be helpful to show the company how much of a certain product should be produced to make a profit out of it.
Page | 195
a) Total Breakeven Point
Table 3.17: Total profit.
Annual Production
Total Cost
Total Revenue
Total Profit
Cans/Year 0 1000000 2000000 3000000 4000000 5000000 6000000 7000000 8000000 9000000 10000000 11000000 12000000 13000000 14000000 15000000 16000000 17000000 18000000 19000000 20000000 21000000 12597389
KD/Year 442053.798 575781.0707 709508.3435 843235.6162 976962.8889 1110690.162 1244417.434 1378144.707 1511871.98 1645599.253 1779326.525 1913053.798 2046781.071 2180508.343 2314235.616 2447962.889 2581690.162 2715417.434 2849144.707 2982871.98 3116599.253 3250326.525 2126668.272
KD/Year 0 168818.182 337636.364 506454.545 675272.727 844090.909 1012909.09 1181727.27 1350545.45 1519363.64 1688181.82 1857000 2025818.18 2194636.36 2363454.55 2532272.73 2701090.91 2869909.09 3038727.27 3207545.45 3376363.64 3545181.82 2126668.31
KD/Year -442053.8 -406962.89 -371871.98 -336781.07 -301690.16 -266599.25 -231508.34 -196417.43 -161326.53 -126235.62 -91144.707 -56053.798 -20962.889 14128.02 49218.929 84309.838 119400.75 154491.66 189582.57 224673.47 259764.38 294855.29 0.0341818
Page | 196
Total Cost
Total Breakeven Point
Total Revenue
4000000 3500000 3000000
2000000 1500000 1000000 500000
0 80 00 00 0 10 00 00 00 12 00 00 00 14 00 00 00 16 00 00 00 18 00 00 00 20 00 00 00
0
60 00 00
40 00 00
0
0 0 20 00 00
KD
2500000
Production Figure 3.2: Total breakeven point.
Page | 197
4. New System A. Overfilling: The National Canned Food Company tends to over fill their products. When over filling, the company is losing money. Depending on how much they over fill and how much they produce of the products they over fill, the company might actually have significant savings if they prevent over filling. In the table on the following page, the annual cost of over filling for each type of product is shown. The over filling is how many grams the product is being overfilled per can. The target is how much the company aims to fill each product. Although we’re working with the 400g cans, almost half of it is filled with brine, and not the problem with increased costs when overfilling. Hence, we’ll only consider the over filling of solid filling (the actually product itself.) The cost per gram is needed to find how much it costs to overfill. This was obtained by the following equation: Cost per gram = Cost per year / (# cans produced per year * target) Then the cost of overfilling in KD per year was obtained using the following equation: Cost of over filling = Amount over filled per year * cost per gram As shown in table 3.40, 68,001.66 KD/year can be saved if they prevent overfilling.
This
represents
about
2.04%
of
their
total
cost.
Given that they tend not to record everything, and that not all variety of products was covered, there is a very big possibility that costs of overfilling are even higher than what was estimated.
Page | 198
Table 3.18: Costs of over filling.
OVER FILLING Overfilling
Production
Target
Overfilling
Annual Cost
Cost Per Gram
Cost of Over Filling
g/can
can/year
g/can
g/year
KD/year
KD/g
KD/year
Baked Beans
-0.17
3,489,494
170
-582,746
83,107
0.0001401
-81.6
Fava Beans
-0.5
75,835
180
-37,918
75,835
0.0055556
-210.7
Green Peas
0.37
7,272,720
188
2,701,088
52,999
0.0000389
105
Hummos Tehina
-1.5
29,494
408
-44,241
29,494
0.002454
-108.6
Mix Vegetables
-2.5
351,936
233
-879,840
32,008
0.0003912
-344.2
Mushroom Pieces
0
182,534
215
0
35,192
0.0008967
0
Mushroom Whole
0
234,864
215
0
43,990
0.0008712
0
Description
TOTAL
67,361.70
Page | 199
B. Transportation Costs The transportation costs of The National Canned Food Company are very high compared to the rest of their costs. It amounts to 14,880 KD/month, which is 178,560 KD/year representing 5.1% of the company’s total cost. Table 3.41 shows the transportation costs and demand for The National Canned Food Company’s different markets. Local transportation costs are considered to be zero since local customers pick up their orders from the warehouse. Transporters for local and regional markets are trucks, while for international markets they are ships. Minimizing
their
transportation
costs
would
lower
their
total
cost.
Table 3.19: Transportation costs of The National Canned Food Company.
1. Transportation Forecast Cost for Year 1: 2009; Avg. Demand
Capacity of
Cost
(transporter/month)
transporter (carton)
(KD/transporter)
Local
28
2100
0
KSA
6
2100
200
UAE
5
2100
300
Bahrain
4
2100
290
Qatar
3
2100
300
Oman
3
2100
400
Iraq
3
2100
150
Tunisia
2
1650
815
USA
3
1650
980
Kenya
3
1650
1300
Totals
122400 cartons/month
14,880 Page | 200
It was noticed that the three markets with the least demand and highest transportation costs were Kenya, USA and Tunisia respectively. Due to increasing yearly demand by approximately 10% annually (see Appendix), the company are barely keeping up with demand, have huge amounts of overtime, and frequent machine breakdowns. Reallocating their demand to local and regional markets seems sensible especially since it costs more than twice the price to ship. Moreover, the amount demanded by each of Tunisia, Kenya, and the US are very small to have any substantial marketing value. The annual costs of the markets to be eliminated and allocated to are represented in tables 3.42 and 3.43. Table 3.20: Annual transportation costs to international markets.
Tunisia USA Kenya Total
Demand Cans/Year 950,400 1,425,600 1,425,600 3,801,600
Shipping Cost KD/year 19,560 35,280 46,800 101,640
Table 3.21: Annual transportation costs to local and regional markets.
Local Regional KSA UAE Bahrain Qatar Oman Iraq Total
Demand Cans/Year 16,934,400.00
Shipping Cost KD/year 0.00
% Total Demand Demand/Total Demand 0.480392157
3,628,800 3,024,000 2,419,200 1,814,400 1,814,400 1,814,400 14,515,200
14,400 18,000 13,920 10,800 14,400 5,400 76,920
0.103 0.086 0.069 0.058 0.051 0.051
In order to produce the 35,869,496 cans annually, The National Canned Food Company is operating their regular 8 hours, and utilizing their maximum overtime of 4 hours. Given these conditions, the maximum capacity the company can produce is 36,691,200 cans annually. Given that the demand is increasing by 10% every year, it can be noticed from Table 3.44 below that The National Canned Page | 201
Food Company won’t be able to cover demand for their local and regional customers. Therefore, it is only sensible to cover the difference in demand by allocating it from the country that is most expensive to send to, Kenya, then the second highest country to send to, US, and last Tunisia. Table 3.22: 2009 shipping costs and allocated demand to local and regional markets.
Local Regional KSA UAE Bahrain Qatar Oman Iraq Total
2009 Demand*
Demand Difference**
Increase 10%
Cans/year
18,627,840
1,693,440
3,991,680 3,326,400 2,661,120 1,995,840 1,995,840 1,995,840 34,594,560
362,880 302,400 241,920 181,440 181,440 181,440 3,144,960
Extra Transporters Needed Yearly***
Allocated Demand****
New Shipping***** Cost KD/year
1,693,440 7 6 5 4 4 4
362,880 302,400 241,920 181,440 181,440 181,440
15,840 19,800 15,312 11,880 15,840 5,940 84,612
* Demand = 2008Demand + (2008 Demand *0.1) ** Demand Difference = 2009 Demand – 2008 Demand *** Extra Trucks Needed Yearly = (Demand Difference/24)/2100 24 cans in a carton 2100 KD per truck **** Allocated Demand (see next page) ***** New Shipping Cost = Shipping Cost + (Extra Trucks*Truck Cost)
Page | 202
Allocated Demand: The demand for 2009 including that for international markets is 38,776,320 cans annually, exceeding the company’s maximum capacity, taking into account a maximum overtime of 4 hours daily, by 2,085,120 cans. Since Kenya is the country that costs most to send to, we’re going to allocate the demand from Kenya to the local and regional markets so satisfy all their demands. Kenya’s demand for 2009 is 1,045,440 cans, but to satisfy the local demand only, Kenya’s entire demand should be allocated to the local markets to cover the difference in demand, as well as 125,280 cans from the US. And since the company won’t be able to cover the demand for the regional markets for 2009, the difference in units should be allocated from The US, since Kenya has already been entirely omitted. The demands for KSA, UAE, Bahrain, Qatar and Oman can all be covered by allocating the demand from the USA. The demand for Iraq, however, won’t be covered from the US alone given that the demand of the US has already been allocated to the other regional countries. Hence, 8640 cans will be allocated from Tunisia to Iraq. Table 3.45 shows the new shipping costs and demand that’s going to be sent to international markets. Given that all the demand for Kenya and the US have been allocated to cover the demand for the local and regional markets, no units will be shipped to them, and Tunisia will have 26 transporters.
Table 3.23: 2009 shipping costs and demand for international markets.
New Demand
Cans Shipped
2009
2009
Tunisia
1,045,440
1,036,800
Total
1,045,440
Number of Transporters Annually 26
New Shipping Cost
KD/year 21,338 21,338
Page | 203
2. Transportation Forecasted Cost for Year 2: 2010; Table 3.46 shows the shipping costs and demand for local and regional markets. Demand forecasts (see appendix) suggests the demand will increase by 10%. In that case, the demand for local and regional markets alone will be 38,054,016 cans. Their maximum capacity, however, is 36,691,200 cans annually. Hence, the demand to Tunisia will not be met, and will be allocated to the local market. Even after the allocation, none of the demand will be met. So, it is going to be assumed that the company will use up their 4 hours of overtime and produce with maximum capacity. Hence, the difference between the maximum capacity and the demand in 2009 will be divided by the number of markets they’re willing to send to, in this case 1 local market, and 6 regional ones. This number will be added to each of the demand for this year to be able to satisfy it as much as possible. When adding those numbers, it can be seen in Table 3.46, that not all markets require this increase. Consequently, the amounts with negative deficit (implying their demand is being exceeded by the number given) will be removed from those markets respectively and added to the local market since it’s the one with the highest deficit. Table 3.24: 2010 demand and demand deficit for local and regional markets.
Demand to Be Met Demand
Demand Deficit Cans/year
Local
18927360
1563264
KSA
4291200
99648
UAE
3625920
33120
Bahrain
2960640
-33408
Qatar
2295360
-99936
Oman
2295360
-99936
Iraq
2295360
-99936
Regional
Page | 204
Table 3.47 shows the shipping costs and demand for local and regional markets after readjusting the demand deficits for the regional customers. Table 3.48 shows what’s left of the international market, Tunisia. Since all of its demand will be allocated to the local market, and the company is already working at maximum capacity, nothing will be sent to Tunisia. So by 2010, The National Canned Food Company will be working at maximum capacity and still won’t be satisfying their local and the two major regional markets.
Table 3.25: 2010 shipping costs and demand for local and regional markets.
2010 Demand*
Increase 10%
Demand To Be Met** Cans/year
Demand Deficit*** Cans/year
Extra Transporters Needed
New Shipping***** Cost KD/year
Yearly**** Local Regional KSA UAE Bahrain Qatar Oman Iraq Total
20,490,624
19,260,576
1,230,048
-
0
4,390,848 3,659,040 2,927,232 2,195,424 2,195,424 2,195,424 38,054,016
4,291,200 3,625,920 2,927,232 2,195,424 2,195,424 2,195,424
99,648 33,120 0 0 0 0
6 6 5 4 4 4
15,589 19,189 14,976 11,592 15,192 6,192 82,729
* 2010 Demand = 2009 Demand + (0.1* 2009 Demand) ** Demand To Be Met =Demand + (Shipped to Tunis/7) + (Capacity-Demand)/7 *** Demand Deficit = Demand 2010 - Demand to be met **** Extra Transporters Needed Yearly = (Demand Difference/24)/2100 24 cans in a carton 2100 KD per truck ***** New Shipping Cost = Shipping Cost + (Extra Trucks*Truck Cost)
Page | 205
Table 3.26: 2010 shipping costs and demand for international markets.
2010 Demand
Tunisia
Increase 10% 1,149,984
Demand Shipped 2010 0
Since the National Canned Food Company is the only can filling company in Kuwait, it is firmly believed that they should first cover their local customers. Since there is a huge deficit in satisfying the local market with 1,230,048 cans annually, a regional market should be omitted to firstly satisfy the local customers to minimize transportation costs. Given all the transportation costs in Table 3.41, Oman’s transportation cost is the most expensive from all the regional shipping costs opposed to the average shipping cost of 248KD of all the other regional countries. So, it is highly recommended that the demand from Oman should be reallocated to the local market, and to KSA, and UAE. Table 3.27: 2010 shipping costs and demand for local and regional markets, considering re-allocating demands from Oman.
Local Regional KSA UAE Bahrain Qatar Oman Iraq Total
Year 2 Demand 10% 20,490,624
Demand To Be Met Cans/year 20,490,624
Transporters Needed Yearly
4,390,848 3,659,040 2,927,232 2,195,424 2,195,424 2,195,424 17,563,392
4,390,848 3,659,040 2,927,232 2,195,424 832,608 2,195,424
87 73 58 44 17 44
-
New Shipping Cost KD/year 0 17,424 21,780 16,843 13,068 6,608 6,534 82,257
Page | 206
3. Transportation Forecast Cost for Year 3: 2011; With a 10% demand increase 3 years from now, the demand deficit for the local customers is going to be very high. So as has been suggested previously, to minimize their costs, the National Canned Food Company should start eliminating one regional market at a time from the highest shipping cost to the lowest to try to prioritize the local market.
Table 3.28: 2011 demand for local and regional markets.
22,539,686
Annual Demand To Be Met 20,717,760
4,829,933 4,024,944 3,219,955 2,414,966 2,414,966 2,414,966 41,859,418
4,390,848 3,659,040 2,927,232 2,195,424 832,608 2,195,424 36,918,336
2011 Demand 10% increase Local Regional KSA UAE Bahrain Qatar Oman Iraq Total
Demand Deficit 1,821,926 439,085 365,904 292,723 219,542 1,582,358 219,542
Re-allocating all the demand from Oman wouldn’t cover the local market, so the country with the second highest shipping cost will start to be omitted to satisfy the local market. In this situation, two countries have a shipping cost of 300KD/month. However, since Qatar has lower demand than the UAE, it should be eliminated first after totally depleting Oman’s demand.
Page | 207
Table 3.29: 2011 demand for local and regional Markets after Oman’s demand has been depleted.
Local Regional KSA UAE Bahrain Qatar Oman Iraq
2011 Demand 10% 22539686
Demand To Be Met 21550368
Demand Deficit 989318
4829932 4024944 3219955 2414966 2414966 2414966
4390848 3659040 2927232 2195424 0 2195424
439084 365904 292723 219542 219542
Since the local market will only require 989,318 cans to fully cover its demand, it will come out of Qatar’s demand. Qatar will also fulfill the demands of other countries with demand deficits. The priority is to provide for the local market of course, and from then on, providing for countries with the least transportation cost. So after the local market, satisfying Iraq’s demand will be prioritized followed by KSA and Bahrain, and finally the UAE since it’s the most expensive to ship to from remaining regions. By doing so, all the regional demands will be satisfied with the exception of some of the UAE’s demands. Table 3.30: 2011 demand and shipping costs for local and regional markets after Oman and Qatar’s demands have been depleted.
Local Regional KSA UAE Bahrain Qatar Oman Iraq TOTAL
Year 3 Demand 10% increase
Demand To Be Met Cans/year
Demand Deficit
Transporters Needed
Shipping Cost
cans/year
Yearly
KD/year
22,539,686
22,539,686
0
0
0
4,829,933 4,024,944 3,219,955 2,414,966 2,414,966 2,414,966 41,859,418
4,829,933 3,686,659 3,219,955 0 0 2,414,966 36,691,200
0 338,285 0 0
96 73 64 0 0 48
19,200 21,900 18,560 0 0 7,200 66,860
Page | 208
4. Transportation Forecast Cost for Year 4; 2012
The UAE has the highest shipping cost from the remaining regional customers, hence demand will be reallocated from the UAE to the local market initially, and then to regional markets from the ones with lower shipping costs to higher ones.
Table 3.31: 2012 demand and demand to be met for local and the remaining regional markets.
Transporters Shipping Needed Cost Yearly KD/year
2012 Demand
Demand To Be Met
Demand Deficit
24793655.04
24,793,655
0
KSA
5312926.08
5,312,926
0
106
21,200
UAE
4427438.4
386,205
4,041,233
8
2,400
Bahrain
3541950.72
3,541,951
0
71
20,590
Iraq
2656463.04
2,656,463
0
53
7,950
TOTAL
40732433.28
36,691,200
Local
0
Regional
52,140
Page | 209
5. Transportation Forecast Cost for Year 5; 2013 The local demand deficit has been covered up by what was left of the UAE demand. The next market that was eliminated was Bahrain since it had transportation costs of 290 KD, compared with 200KD, and 150KD for each of KSA and Iraq respectively. Therefore, UAE and Bahrain are not going to be covered anymore, and the only regional markets remaining are KSA, and Iraq. Table 3.32: 2013 demand and shipping costs for local and the remaining regional markets.
2013 Demand Local 27,273,021 Regional KSA 5,844,219 UAE 4,870,182 Bahrain 3,896,146 Iraq 2,922,109 TOTAL 44,805,677
Demand To Be Met Cans/year 27,273,021 5,844,219 0 651,851 2,922,109 36,691,200
Demand Deficit Cans/year 0
Transporters Needed Yearly
Shipping Cost KD/year
0 3,244,295 0
116
23,191
13 58
3,751 8,697 35,639
6. Transportation Forecast Cost for Year 6; 2014 Bahrain has the highest transportation cost from the remaining regional customers. Hence, its demand will be allocated first to the local market and then to Iraq. Finally, what’s left is allocated to the KSA to cover their demand deficit. Table 3.33: 2014 demand and shipping costs for local and the remaining regional markets.
Demand Deficit Cans/year 0
Transporters Needed Trucks/year
Shipping Cost KD/year
30,000,323
Demand To Be Met Cans/year 30,000,323
6,428,641 3,214,320 43,929,044
3,476,557 3,214,320 36,691,200
2,952,084 0 7,237,844
69 64 728
13,796 18,495 32,291
2014 Demand Local Regional KSA Iraq TOTAL
Page | 210
6. Transportation Forecast Cost for after Year 6 The National Canned Food Company should follow the same procedure by forecasting demand and eliminating the markets that have the highest transportation costs by allocating their demands to the local market and then other regional markets which are cheaper to send to. Eventually, the total shipping cost would go down to 0 KD/year given that there is no transportation costs for the local market because the customer picks up the products from the National Canned Food Company’s warehouse.
New Fixed Cost = Total Fixed Cost – Transportation Cost = 442,053.86 – 178,560 = 263,493.86 KD/year New Total Cost = Total Cost – Total Fixed Cost + New Fixed Cost = 3,518,913.44 - 442,053.86 + 263,493.86 = 3,340,353.44 KD/year Savings in Total Cost =
3,518,913.44 - 3,340,353.44
= 178,560 KD
Page | 211
5. Conclusion The costs of the National Canned Food Company were classified into direct, indirect, technical overheads, company overheads, and marketing overheads costs. From those costs, the variable and fixed costs were calculated. The total cost was found to be 3,518,913.44 KD/year. The total revenue and total profits were also calculated and found to be 4,274,967.57 KD/year and 755,911.15 KD/Year, respectively, with a profit margin of 17.48%. This number suggests that the company is doing quite well. The total productivity of the National Canned Food Company was calculated to be 1.214 which is greater than 1, suggesting the company is productive. The breakeven point for the company was also obtained as well as the breakeven point for each individual product. This can help the company decide how much of each product to produce in order to make a profit. The total breakeven point was 12,597,389 cans, which means they broke even in a quarter of a year, which is quite reasonable. Although the numbers seem rather outstanding, when further analysis was done, it was noticed that the company has very high material costs due to overfilling their products. The cost of overfilling for each product was calculated and the total overfilling cost was found to be 68,001.8 KD/year. Another major cost issue the company was facing is the very high transportation costs of 178,560 KD/year. When the transportation costs were analyzed in detail, it was noticed that the National Canned Food Company had three major markets, local, regional and international. The international markets were the smallest customers with the highest transportation costs. Using demand forecasts, it was observed that within the next 2 years, the company would not be able to meet even its local customers because they’d already be producing at maximum capacity. Thus, it only seemed logical to start re-allocating their demands from their international markets to local and regional ones. The priority was given to the local market, due to the company being the only supplier and the fact that there is no local transportation cost, and then supplying markets with lower transportation costs. By eliminating one market at a time through the year, eventually the National Canned Food Company will only supply the local market and there would be no transportation costs, lowering their total cost to 3,340,353.44 KD, saving 178,560 KD. Page | 212
If the National Canned Food Company takes into consideration the analysis of this study, they would eventually be saving 68,001.6 KD annually due to overfilling in addition to 178,560 KD annually due to transportation costs. Overall, the company would be saving 246,561.8 KD yearly. This figure represents 7% of their total costs, and is considered substantial savings in the long run.
Page | 213
Page | 214
4. Production Line Analysis and System Maintenance
Page | 215
Page | 216
4.1 Introduction
The factory has two lines (can making line and can filling line) and both lines are continuous and the machines are connected in series, hence the failure of one machine causes the stoppage of the whole line, adversely affecting the production rate of the factory. Thus, it is important to analyze the maintenance system of the factory. The maintenance policies that the factory currently applies were studied and the reliability and availability of the factory were calculated. The performance of the factory was improved by introducing better maintenance policies to reduce the failure rate of the different machines. Since analytical methods assume very simple situations and do not apply to the factory’s situation, the as-is layout was modeled using Arena simulation software to analyze and improve it. For both lines, only 400 g size cans were considered since most of the factory production is of this size. For example, the production of the most recent four months was as follows: Table 4. 6: The production for July, August, September, and October.
Month
400 g
220 g
450 g
(cartons) (cartons) (cartons)
Total
400 g
220 g
450 g
(cartons) (%)
(%)
(%)
July
38142
1340
7120
46602
81.8
2.9
15.3
August
61767
1671
0
63438
97.4
2.6
0
September
62006
2471
1558
66035
93.9
3.7
2.4
October
26685
1976
0
28661
93.1
6.9
0
Total of 4
188600
7458
8678
204736
92.1
3.6
4.2
months
Page | 217
4% 4% 400 g 92%
200 g 450 g
Figure 4.2: Pie chart of the production of four months sample.
Problem Statement The current maintenance schedule causes too much downtime and is not optimized. The reliability of the can filling line is too low. The process can barely keep up with demand.
Objectives
Improve the system reliability.
Increase the daily production.
Reduce the maintenance cost.
Solution Approach New maintenance plans were proposed that increased machine reliability and availability while minimizing the maintenance cost. These plans were evaluated using Arena simulation software to choose the best alternative amongst them, after verifying and validating the Arena models.
Page | 218
4.2 Part List
Part lists provide a listing of the components of the product. A part list includes part number, part name, and number of parts per product. Table 4. 7: Part list of 400 g canned food.
Company National Canned Food Co.
Prepared by: -
Product
Date: -
400 g canned food
Part NO.
Part Name
Quantity Material
Size (cm)
Make/Buy
001
Sheet metal
1
23 x 11
Buy
Coated
8 cm
Buy
Steel
diameter
Coated Steel
002
Lid
2
003
Label
1
Paper
23 x 8
Buy
004
Food
240 g
-
-
Buy
Page | 219
4.3 Bill of Materials (BOM)
The Bill of materials is a product structure hierarchy refereeing to the level of the product assembly. Level 0: Final product. Level 1: Subassemblies and components that feed directly to the final product. Level 2: Subassemblies and components that feed directly to level 1.
400 g Canned Food
Level 0 Level 1 Level 2
Empty can
Sheet metal 001
Food 004
Upper lid 002
Label 003
Lower lid 002
Figure 4.3: BOM of 400 g cans.
Page | 220
4.4 Component Part Drawing A component part drawing provides the part specifications and dimensions in sufficient detail to allow part fabrication.
D=8 cm 002
Figure 4.4: Component No. 002 (Lid)
23 cm
001
11 cm [Type a quote from the document or the summary of an interesting point. You can position the text box anywhere in the document. Use the Text Box Tools tab to change the formatting of the pull quote text box.]
Figure 4.5: Component No. 001 (400 g canned food).
Page | 221
Final Product
Figure 4.6: Final product (Canned food).
Page | 222
4.5 Process Description
The factory consists of two lines; the can making line and the can filling line. The process of the Can Making Line can be described as follows: Slitting: Tin sheets are cut into blanks of desired dimensions Blanks are manually fed to the welder Welding: the two ends of the blanks are welded to form a cylindrical shape Welded blanks are transported to the lacquering machine by the conveyer belt Lacquering: applying a varnish coat in the inner face of the welded blanks Curing: in this process the welded blanks are moved to the flanging machine by a magnetic belt and the varnished is cured and dried during this process Flanging: can is flanged at both ends to prepare it for seaming Seaming: one end of the can is seamed by a seamer Palletizing: every 2940 cans are place in a pallet and moved by a forklift to the empty can storage area. Note: The can production line follows FIFO (First in First out) procedure. Therefore, the stored empty cans are taken to the filling line, first.
Page | 223
The process of the can filling line can be described as follows: Soaking: the food is soaked for 8-14 hours in a hopper depending on the type of food (Peas, kidney beans, mushroom, etc). The factory has a total of five hoppers and the capacity of each hopper is 3000 Kg (meat and corn do not go into this process). Reel washing: the food is cleaned by showering and the excess water is drained. The food is transported to the blancher by a bucket elevator. Blanching: the food is blanched for 5 to 30 minutes to release gases and enzymes. De-stoning: the food is moved to the de-stoner to remove stones. Inspection belt: the food is sorted manually to remove any dark or broken pieces. The food is held in the filling hopper. Solid filling: the empty can is filled with solid food. Liquid filling: a liquid solution is added to the can. The can is vacuumed by the shower filler machine under a temperature of 75 °C to 85 °C. This process makes the expiry date of the canned food longer and protects consumers. Seaming: the other lid is seamed to the can using double seaming. Coding: a code is printed on the lid of the can using the coding machine to show the production and expiration dates of the product. Crate loading: 700 cans are put on a crate, and 7 layers of crates are taken to sterilizing the stage by a trolley. Sterilizing: the can in the crates are sterilized under a temperature of 121ºC. This process takes between 10 and 70 minutes depending on the type of product and the type of liquid used. Then, it is cooled suddenly to kill the remaining bacteria. The cans are then dried. Crate unloading: the cans are unloaded from the crate to the labeler. Labeling: the cans are labeled by the labeling machine. Page | 224
Label inspection: The labels are checked to determine whether they were applied correctly. Packaging: 12 cans are kept in a tray. Two trays are then wrapped together by the shrink wrapper. Every 20 cartons are put in a pallet by two workers and one fork lift. Storing: the final products are stored for four days before a sample is taken to carry out three types of tests (physical, chemical and biological), ensuring that the product meets standard and is ready for distribution. Notes: Cans are de-palletized before entering the filling line. In the filling line, empty cans are sterilized by hot water and steam while preparing the beans. The liquid solution is prepared prior production hours.
Page | 225
4.6 Process Flow on the Factory Layout
Figure 4.7: Process flow on the factory layout.
Page | 226
4.7 Operation Process Chart Company: National Canned Food Production and Trading Company
Prepared by:__________
Products: Can Making Line
Date:________________
Sheet Metal 001
011
Slitting
021
Welding
031
Lacquering
041
Curing
051
Flanging
Lid 002
SA1
071
Seaming Palletizing
Figure 4.8: Operation Process Chart for the can making line.
Page | 227
Company: National Canned Food Production and Trading Company
Prepared by:__________
Products: Can filling Line
Date:________________
Empty Can From store
013
023
Food 004
De-palletizing Sterilizing
012
Soaking
022
Reel Washing
032
Blanching
042
De-stoning
I1
Inspection Belt
SA
Solid Filling
2
072
Liquid Filling
A1
Seaming
092
Coding
102
Crate Loading
112
Sterilizing
122
Crate Unloading
A2
Labeling
Lid 00 2
Label 003
I2
Label Inspection
152
Packaging
I3
Testing
Figure 4.9: Operation process chart for the can filling line.
Page | 228
4.8 Route sheets
Table 4. 8: Route sheet of sheet metal.
Company: National Canned Food Production and Trading co. Produce:
Part Name: Sheet Metal
Part No.: 001
Prepared By: Date:
Operation Operation No. Description
Machine Rate
Materials or Parts Description
Machine Type
Dept.
011
Slitting
Slitting Machine
Coated Steel sheet metal Production 500 sheets/hr 23x11 cm
021
Welding
Welder
Production 160 cans/min
031
Lacquering
Lacquering Machine
Production 160 cans/min
041
Curing
Curing Machine
Production 160 cans/min
051
Flanging
Flanging Machine
Production 160 cans/min
071
Palletizing
Palletizer
Production
Page | 229
Table 4. 9: Route sheet of lid.
Company: National Canned Food Production and Trading co. Produce:
Part Name: Lid
Part No.: 002
Prepared By: Date:
Operation Operation
Operation
Materials or Parts
Time
Description
No.
Description
Machine Type
Dept.
SA1/A1
Seaming
Seamer
Production 500 sheets/hr
Lid 8 cm in diameter
Page | 230
Company: National Canned Food Production and Trading co. Produce:
Part Name: Food
Part No.: 004
Prepared By: Date:
Operation No.
Operation Description
Machine Type
Dept.
Machine Rate
012
Soaking
Hopper
Production
8-14 hours
022
Reel Washing
Shower
Production
032
Blanching
Blancher
Production
042
Destoning
Destoner
Production
I1
Inspection Belt
Inspection Belt
Production
SA2
Solid Filling
Solid Filler
Production
072
Liquid Filling
Liquid Filler
Production
092
Coding
Coding Machine
Production
102
Crate Loading
Crate Loader
Production
112
Sterilizing
Retort
Production
122
Crate Unloading
Crate Unloader
Production
A2
Labeling
Labeler
Production
I2
Label Inspection
152
Packaging
Shrink Wrapper
Production
30 cartons/min
I3
Inspection
-
QC Lab
4 days
Materials or Parts Description
5-30 min
140 cans/min
10-70 min
140 cans/min
Production
Page | 231
4.9 Data Collection and Fitting
The following table shows the demand inter-arrival distributions and the quantity distributions of each product. Table 4. 10: Distribution summary of inter-arrival and quantity of the demand.
Demand Inter-arrival1
Quantity2
(Days)
(Cartons)
Fava beans
0.5 + 8 * BETA(0.568, 1.52)
50 + 2.83e+003 * BETA(0.577, 0.802)
Peas
0.5 + WEIB(2.7, 1.5)
UNIF(50, 2.31e+003)
Chickpeas
0.5 + WEIB(1.95, 1.33)
470 + 2.59e+003 * BETA(0.889, 0.774)
Beans
0.5 + 7 * BETA(0.827, 2.05)
79 + 3.1e+003 * BETA(0.603, 1.26)
Corn
UNIF(1.5, 17.5)
TRIA(103, 188, 957)
Mushroom
0.5 + EXPO(7.05)
NORM(412, 230)
Entity
For more information about the daily production of the two lines, see Appendix (B).
1 2
See Appendix (F) for more details See Appendix (E) for more details
Page | 232
Table 4. 11: Summary of the mean time between failure (MTBF) of the machines and their repair time.
MTBF
Repair time
(Days)
(Min)
-0.5 + EXPO(5.16)
4.66
60
Palletizer/De-Palletizer
-0.5 + EXPO(12.2)
11.7
30
Process Line
-0.5 + EXPO(8.37)
7.87
30
Fillers and Seamer
-0.5 + EXPO(6)
5.5
60
Crate Loader
0.999 + EXPO(18.8)
19.799
5
Retort
-0.5 + EXPO(18.8)
18.3
30
Crate Unloader
1.5 + EXPO(23.2)
24.7
5
Labeler
-0.5 + EXPO(7.55)
7.05
60
Shrink Wrapper
0.999 + EXPO(13.5)
14.499
60
Machine3
MTBF4 Distribution (Days)
Can Plant
The MTBF in the table above is calculated as follows MTBF = E(X+EXPO(1\λ)) = X + 1\λ For example the MTBF of the can plant is E(-0.5 + EXPO(5.16)) = -0.5 + 5.16 = 4.66 days.
3 4
For more information about the machines, see Appendix (A) See Appendix (H) for more details
Page | 233
4.10 Maintenance Types
The factory has two types of maintenance; corrective maintenance and preventive maintenance.
Corrective Maintenance (CM)
Corrective maintenance is unscheduled maintenance actions performed as a result of system failure, to restore the system to specified condition. The failure rate λ = 1/MTBF Table 4. 12: Summary of the MTBF and the failure rate of the machines.
Failure Rate λ
Machine
MTBF (Days)
Palletizer/De-Palletizer
11.7
0.085
Process Line
7.87
0.127
Fillers and Seamer
5.5
0.182
Crate Loader
19.799
0.051
Retort
18.3
0.055
Crate Unloader
24.7
0.04
Labeler
7.05
0.142
Shrink Wrapper
14.499
0.069
Can Plant
4.66
0.215
(Failure/day)
Page | 234
Preventive Maintenance (PM)
Preventive maintenance is all scheduled maintenance actions performed to retain a system in a specified condition. The factory performs preventive maintenance once a month (every 26 days) during non-production hours and it takes 10 hours. f = 1/26 = 0.0385 preventive maintenance/day
Page | 235
4.11 Maintenance Plan
Maintenance Model
Corrective maintenance is done by one mechanical technician, one electrician and one helper.
Preventive maintenance is done by two mechanical technicians, two electricians and two helpers.
Preventive maintenance is applied during non-production days, and lasts for 10 hours.
Mechanical technicians and electricians are paid 170 KD/month
Helpers are paid 50 KD/month.
26 days/month *12 month/year *10 hours/year = 3120 hours/year
Production rate of filling line = 140 cans/min
Production rate of can making line = 160 cans/min
Revenue/can = 0.232955 KD
CM Cost = (Mct/MTBF) * 3120 * cost/hr
PM Cost = fpt * Mpt * 3120 * cost/hr
Production Loss Cost= # units/min * Mct * λ * 3120 * Rev/unit
The new failure rate of the machine is calculated using the following equation: 1
𝑀𝑇𝐵𝑀 = 𝜆+𝑓 , by keeping the MTBM of the current maintenance plan the same and changing the preventive maintenance rate.
Page | 236
Current Maintenance Plan The factory currently applies preventive maintenance once a month (every 26 days). The following table shows the failure rate, PM rate and the mean time between maintenance (MTBM) of each machine.
Table 4. 13: Summary of the failure rate, preventive maintenance rate, and mean time between maintenance (MTBM) of the machines.
Machine
Failure Rate (failure/day)
PM Rate (actions/day)
MTBM (days)
Palletizer/De-Palletizer
0.085
1/26
8.07
Process Line
0.127
1/26
6.04
Fillers and Seamer
0.182
1/26
4.54
Crate Loader
0.051
1/26
11.23
Retort
0.055
1/26
10.74
Crate Unloader
0.040
1/26
12.66
Labeler
0.142
1/26
5.54
Shrink Wrapper
0.069
1/26
9.30
Can Plant
0.215
1/26
3.95
Page | 237
The annual corrective and preventive maintenance costs and the production loss cost of the current maintenance plan were also calculated. Table 4. 14: Summary of the corrective maintenance (CM) cost, preventive maintenance (PM) cost, and production loss cost of the machines.
CM Cost
PM Cost
Production Loss Cost
(KD/year)
(KD/year)
(KD/year)
Palletizer/De-Palletizer
20
72.07
26,090.960
Process Line
29.733
72.07
38,788.340
Fillers and Seamer
85.091
36.04
111,005.175
Crate Loader
1.970
18.02
2,569.694
Retort
12.787
36.04
16,681.106
Crate Unloader
1.579
18.02
2,059.813
Labeler
66.383
18.02
86,599.782
Shrink Wrapper
32.278
18.02
42,108.315
Can Plant
100.429
72.07
131,014.692
Total
350.25
360.36
456,917.88
Machine
Total Cost = CM cost + PM cost + Production loss cost = 350.25 + 360.36 + 456,917.88 = 457,628.5 KD/year.
Page | 238
Proposed Maintenance Plans Three alternative maintenance plans were proposed. They are as follows:
Alternative 1 Alternative proposed applying additional preventive maintenance actions twice a month (every 13 days), instead of once a month (every 26 days), during nonproduction days. This should reduce the failure rates of the machines. By keeping the MTBM of the current maintenance plan the same, the following results were obtained: Table 4. 15: Summary of the new failure rate, preventive maintenance rate, and mean time between maintenance (MTBM) of the machines.
Machine
Failure Rate
PM Rate (action/day)
MTBM (days)
(failure/day) Palletizer/De-Palletizer
0.047
1/13
8.07
Process Line
0.089
1/13
6.04
Fillers and Seamer
0.143
1/13
4.54
Crate Loader
0.012
1/13
11.23
Retort
0.016
1/13
10.74
Crate Unloader
0.002
1/13
12.66
Labeler
0.103
1/13
5.54
Shrink Wrapper
0.031
1/13
9.30
Can Plant
0.176
1/13
3.95
Page | 239
The annual corrective and preventive maintenance costs and the production loss cost of alternative 1 were also calculated as follows: Table 4. 16: Summary of the corrective maintenance (CM) cost, preventive maintenance (PM) cost, and production loss cost of alternative 1.
Production
CM Cost
PM Cost
(KD/year)
(KD/year)
Palletizer/De-Palletizer
11.010
143.99
14,362.708
Process Line
20.743
143.99
27,060.088
Fillers and Seamer
67.110
72.00
87,548.672
Crate Loader
0.471
36.00
614.985
Retort
3.797
72.00
4,952.854
Crate Unloader
0.081
36.00
105.104
Labeler
48.402
36.00
63,143.279
Shrink Wrapper
14.298
36.00
18,651.812
Can Plant
82.449
143.99
107,558.188
Total
248.360
719.97
323,997.689
Machine
Loss Cost (KD/year)
Total Cost = CM cost + PM cost + Production loss cost = 248.360 + 719.97 + 323,997.689 = 324,966 KD/year. Alternative 1 reduced costs by 29%.
Page | 240
Alternative 2 This alternative proposed applying preventive maintenance weekly (every 5 days) during non-production days. Once again, the same MTBM was used and the following results were obtained: Table 4. 17: Summary of the new failure rate, preventive maintenance rate, and mean time between maintenance (MTBM) of the machines.
Machine
Failure Rate (failure/day)
PM Rate (action/day)
MTBM (days)
Palletizer/De-Palletizer
-0.076
1/5
8.07
Process Line
-0.034
1/5
6.04
Fillers and Seamer
0.020
1/5
4.54
Crate Loader
-0.111
1/5
11.23
Retort
-0.107
1/5
10.74
Crate Unloader
-0.121
1/5
12.66
Labeler
-0.020
1/5
5.54
Shrink Wrapper
-0.093
1/5
9.30
Can Plant
0.053
1/5
3.95
Since only the fillers and seamer and the can plant have positive failure rates, they are the only machines were performing preventive maintenance actions every week is applicable. Thus, alternative 2 reduces to: Applying PM weekly on the fillers and seamer and the can plant, and twice a month on the remaining machines.
Page | 241
Table 4. 18: Summary of the new failure rate, preventive maintenance rate, and mean time between maintenance (MTBM) of the machines.
Machine
Failure Rate (failure/day)
PM Rate (action/day)
MTBM (days)
Palletizer/De-Palletizer
0.047
1/13
8.07
Process Line
0.089
1/13
6.04
Fillers and Seamer
0.020
1/5
4.54
Crate Loader
0.012
1/13
11.23
Retort
0.016
1/13
10.74
Crate Unloader
0.002
1/13
12.66
Labeler
0.103
1/13
5.54
Shrink Wrapper
0.031
1/13
9.30
Can Plant
0.053
1/5
3.95
Page | 242
The annual costs of alternative were found to be as follows: Table 4. 19: Summary of the corrective maintenance (CM) cost, preventive maintenance (PM) cost, and production loss cost of alternative 2.
Machine
CM Cost
PM Cost
(KD/year)
(KD/year)
Production Loss Cost (KD/year)
Palletizer/De-Palletizer
11.010
143.99
14,362.708
Process Line
20.743
143.99
27,060.088
Fillers and Seamer
9.50
187.2
12,404.828
Crate Loader
0.471
36.00
614.985
Retort
3.797
72.00
4,952.854
Crate Unloader
0.081
36.00
105.104
Labeler
48.402
36.00
63,143.279
Shrink Wrapper
14.298
36.00
18,651.812
Can Plant
24.847
187.2
32,414.344
Total
133.157
878.379
173,710.0026
Total Cost = CM cost + PM cost + Production loss cost = 133.157 + 878.379 + 173,710.0026 = 174,721.5 KD/year. Alternative 2 reduced the cost by 61.8%.
Page | 243
Alternative 3: In this alternative, it was suggested that PM be applied just before the failure occurs (Reliability centered maintenance). Table 4. 16 shows the MTBF of the current policy and the suggested mean time between preventive maintenance (MTBPM). Table 4. 20: Summary of the current MTBF and the proposed MTBPM.
MTBPM Machine
MTBF (days) (days/action)
Palletizer/De-Palletizer
11.7
11.6
Process Line
7.87
7.77
Fillers and Seamer
5.5
5.4
Crate Loader
19.799
19.70
Retort
18.3
18.20
Crate Unloader
24.7
24.60
Labeler
7.05
6.90
Shrink Wrapper
14.499
14.40
Can Plant
4.66
4.56
Page | 244
Using the same MTBM of the current policy and the suggested mean time between preventive maintenance, the following results are obtained: Table 4. 21: Summary of the new mean time between failures.
MTBFnew
Failure Rate
(days)
λ(Failure/day)
Palletizer/De-Palletizer
26.51
0.038
Process Line
27.15
0.037
Fillers and Seamer
28.49
0.035
Crate Loader
26.17
0.038
Retort
26.20
0.038
Crate Unloader
26.11
0.038
Labeler
28.27
0.035
Shrink Wrapper
26.33
0.038
Can Plant
29.62
0.034
Machine
Page | 245
The annual corrective and preventive maintenance costs and the production loss cost for alternative 3 were found to be as follows:. Table 4. 22: Summary of the corrective maintenance (CM) cost, preventive maintenance (PM) cost, and production loss cost of alternative 3.
Machine
CM Cost
PM Cost
(KD/year)
(KD/year)
Production Loss Cost (KD/year)
Palletizer/De-Palletizer
8.83
72
11,516.01
Process Line
8.62
72
11,241.73
Fillers and Seamer
16.42
36
21,426.21
Crate Loader
1.49
18
1,943.78
Retort
8.93
36
11,649.28
Crate Unloader
1.49
18
1,948.45
Labeler
16.56
18
21,599.26
Shrink Wrapper
17.78
18
23,189.42
Can Plant
15.80
72
20,608.73
Total
95.91
360.00
125,122.87
Total Cost = CM cost + PM cost + Production loss cost=125,578.78 KD/year. The cost has been reduced by 72.56%.
Page | 246
4.12 The Reliability of the Lines
Reliability is the probability that the system will perform in a satisfactory manner for a given period of time, when used under specified operating conditions. It is calculated with the following equation: R (T) = e-λt , where λ is the failure rate and t is the given period of time. Table 4. 23: Summary of the mean failure rate of the machines and their reliability over one day.
Failure Rate
Reliability over
λ(Failure/day)
one day (%)
Palletizer/De-Palletizer
0.085
91.81
Process Line
0.127
88.07
Fillers and Seamer
0.182
83.38
Crate Loader
0.051
95.07
Retort
0.055
94.68
Crate Unloader
0.040
96.03
Labeler
0.142
86.78
Shrink Wrapper
0.069
93.34
Can Plant
0.215
80.69
Machine
Page | 247
Alternative 1:
Table 4. 24: Summary of the failure rate of the machines and their reliability over one day for alternative 1.
Failure Rate
Reliability over
Improvement
λ(Failure/day)
one day (%)
(%)
Palletizer/De-Palletizer
0.047
95.40
3.91
Process Line
0.089
91.52
3.92
Fillers and Seamer
0.143
86.64
3.91
Crate Loader
0.012
98.80
3.92
Retort
0.016
98.39
3.92
Crate Unloader
0.002
99.79
3.92
Labeler
0.103
90.17
3.91
Shrink Wrapper
0.031
96.99
3.91
Can Plant
0.176
83.85
3.91
Machine
Page | 248
Alternative 2:
Table 4. 25: Summary of the failure rate of the machines and their reliability over one day for alternative 2.
Failure Rate
Reliability over
Improvement
λ(Failure/day)
one day (%)
(%)
Palletizer/De-Palletizer
0.047
95.40
3.92
Process Line
0.089
91.52
3.92
Fillers and Seamer
0.020
97.99
17.53
Crate Loader
0.012
98.80
3.92
Retort
0.016
98.39
3.92
Crate Unloader
0.002
99.79
3.92
Labeler
0.103
90.17
3.92
Shrink Wrapper
0.031
96.99
3.92
Can Plant
0.053
94.83
17.53
Machine
Page | 249
Alternative 3:
Table 4. 26: Summary of the failure rate of the machines and their reliability over one day for alternative 3.
Failure Rate
Reliability over
Improvement
λ(Failure/day)
one day (%)
(%)
Palletizer/De-Palletizer
0.038
96.30
4.89
Process Line
0.037
96.38
9.44
Fillers and Seamer
0.035
96.55
15.80
Crate Loader
0.038
96.25
1.24
Retort
0.038
96.26
1.66
Crate Unloader
0.038
96.24
0.22
Labeler
0.035
96.52
11.23
Shrink Wrapper
0.038
96.27
3.15
Can Plant
0.034
96.68
19.82
Machine
Page | 250
4.13 Results
Can Making Line
Can Plant
Figure 10: Schematic illustration of the can production line.
Current Maintenance Plan From Table 4. (19) and Figure (9), it was concluded that the reliability of the can production line is 80.65%.
Proposed Maintenance Plan Alternative 1: From Table (20) and Figure (9), it was concluded that the reliability of the can making line has become 83.85%, an increase of 3.91%. Alternative 2: From Table (21) and Figure (9), it was concluded that the reliability of the can making line has become 94.83%, an increase of 17.53%. Alternative 3: From Table (22) and Figure (9), it was concluded that the reliability of the can making line has become 96.68%, an increase in of 19.82%.
Page | 251
Can Filling Line
Palletizer/ DePalletizer (1) Crate
Fillers & Seamer
Crate
(3)
Loader
Retort (5)
Shrink
unloader
Labeler
Wrapper
(6)
(7)
(8)
(4)
Process Line (2)
Figure 11: Schematic illustration of the can filling line.
Current Maintenance Plan From Table (19) and Figure (10), it was concluded that the reliability of the can filling line is R(1 day) = [1-(1-R1)(1-R2)] (R3) (R4) (R5) (R6) (R7) (R8) = [1-(1-0.9181)(1-0.8807)](0.8338)(0.9507)(0.9468)(0.9603)(0.8678)(0.9334) = 0.5781 = 57.81% Proposed Maintenance Plan Alternative 1: From Table (20) and Figure (9); R(1 day) = [1-(1-R1)(1-R2)] (R3) (R4) (R5) (R6) (R7) (R8) = [1-(1-0.9540)(1-0.9152)](0.8664)(0.9880)(0.9839)(0.9979)(0.9017)(0.9699) = 0.7322 = 73.22%
Page | 252
It can be concluded that the reliability of the can filling line has become 73.22%, an increase of 26.65%.
Alternative 2: From Table (20) and Figure (9); R(1 day) = [1-(1-R1)(1-R2)] (R3) (R4) (R5) (R6) (R7) (R8) = [1-(1-0.9540)(1-0.9152)](0.9799)(0.9880)(0.9839)(0.9979)(0.9017)(0.9699) = 0.8281 = 82.81% It can be concluded that the reliability of the can filling line has become 82.81%, an increase of 43.24%. Alternative 3: From Table (20) and Figure (9); R(1 day) = [1-(1-R1)(1-R2)] (R3) (R4) (R5) (R6) (R7) (R8) = [1-(1-0.9630)(1-0.9638)](0.9655)(0.9625)(0.9626)(0.9624)(0.9652)(0.9627) = 0.7989 = 79.89% It can be concluded that the reliability of the can filling line has become 79.89%, an increase of 38.19%.
Page | 253
4.14 Availability of the Machines
Availability is the percentage of time or the probability that a system will be ready or available when required. Availability is expressed differently; three common Figures of Merit (FOM) are defined below:
Inherent Availability (Ai): Probability that an equipment (or system), when used under stated conditions in an ideal support environment (i.e. readily available tools, spares, maintenance personnel, etc), will operate satisfactorily at any time as required. It excludes: Preventive/scheduled maintenance. Logistic Delays (maintenance down time that is expended as a result of waiting for a spare part to become available, waiting for the availability of testing equipment, waiting for use of a facility, etc). Administrative delays (portion of down time during which maintenance is delayed for administrative reasons). The Inherent Availability is calculated with the following equation: 𝑀𝑇𝐵𝐹
Ai= 𝑀𝑇𝐵𝐹 +𝑀 𝐶𝑇 Where, MTBF = mean time between failures 𝑀CT = mean corrective maintenance time
Page | 254
Achieved Availability (Aa) The probability that a system or equipment, when used under stated conditions in an ideal support environment (i.e. readily available tools, spares, personnel etc.) will operate satisfactorily at point in time. This definition (Aa) is similar to that of Ai. However, preventive maintenance is included. It excludes the logistic delays, administrative delays etc.
The Achieved Availability is calculated with the following equation: 𝑀𝑇𝐵𝑀
Aa= 𝑀𝑇𝐵𝑀 +𝑀 Where, MTBM = Mean time between maintenance 𝑀=Mean active maintenance time And MTBM & 𝑀 are a function of corrective and preventive maintenance actions.
Operational Availability (Ao) Probability that system or equipment, when used under stated conditions in an actual operational environment, will operate satisfactorily when called upon. 𝑀𝑇𝐵𝑀
Ao=𝑀𝑇𝐵𝑀 +𝑀𝐷𝑇 Where MDT=Mean Maintenance Down Time.
Page | 255
Table 4. 27: Summary of the availability of the machines.
Machine
Ai (%)
Aa (%)
Ao (%)
Palletizer/De-Palletizer
99.57
95.90
60.15
Process Line
99.37
95.71
53.40
Fillers and Seamer
98.21
94.64
46.33
Crate Loader
99.96
96.25
67.39
Retort
99.73
96.04
66.36
Crate Unloader
99.97
96.26
69.75
Labeler
98.60
95.00
51.17
Shrink Wrapper
99.32
95.66
63.18
Can Plant
97.90
94.34
43.00
Page | 256
4.15 Spare Parts
Data related to the spare parts required for each machine and the number ordered per year was collected. The factory orders some of the spare parts locally and some others from the UK, Germany and Italy. The following table shows each machine, its spare parts and the number ordered per year. Table 4. 28: Summary of the machines, spare parts, and the number ordered per year.
Machine
Plletizer/De-Palletizer
Spare Part
No. of orders per year
Sensors
2
Bearings
4
Pneumatics valves
2
Sprocket
1
Shaft
10
Rollers
1
Belt
5
Sprocket
4
Bearings
7
Clutch
1
Seaming roller
4
Chuck
8
Bearings
2
Sprocket
1
Process Line
Fillers and Seamer
Crate Loader
Page | 257
Machine
Retort
Spare Part
No. of orders per year
Electrical fuses
4
Conductors
1
Pipe fittings
10
Gasket
25
Valves
4
Bearings
2
Conductors
2
Electric motor
2
Driving belt
1
Belt
3
Glue valves
2
Electrical fuses
4
Bearings
5
Glue nozzle
2
Glue Filters
2
Conductors
2
Belt
2
Bearings
12
Belt
5
Sprocket
4
Crate Unloader
Labeler
Shrink Wrapper
Can Plant
Page | 258
Machine
Spare Part
No. of orders per year
Conductors
4
Cylinder
1
Page | 259
4.16 System Simulation
Nowadays, manufacturers are facing rapid and fundamental changes in the ways business is done. Producers are looking for simulation systems increasing throughput and profit, reducing cycle time, improving due-date performance and reducing WIP. Manufacturing systems, often requiring large investments in capital, equipment and supporting software, are costly and time-consuming to acquire, integrate, and operate. Simulation technology is a tool of proven effectiveness in improving the efficiency of manufacturing system design, operation, and maintenance. Simulation models can be used to perform “what-if” analyses and make better-informed decisions. Manufacturing simulation has been one of the primary application areas of simulation technology. It has been widely used to improve and validate the designs of a wide range of manufacturing systems.. The following are some of the specific issues that simulation is used to address in manufacturing systems:
The quantity of equipment:
Number and type of machines for a particular objective.
Number, type, and physical arrangement of transporters, conveyors, and other support equipment (pallets and forklifts).
Location and size of inventory buffers.
Evaluation of a change in product volume or mix.
Labor-requirements planning.
Performance evaluation:
Throughput analysis.
Time-in-system analysis.
Bottleneck analysis.
Page | 260
Evaluation of operational procedures:
Production scheduling.
Control strategies.
Reliability analysis (effect of preventive maintenance).
Following are some of the performance measures commonly estimated by simulation:
Throughput.
Time in system for parts.
Time parts spend in queues.
Queue sizes.
Timeliness of deliveries.
Utilization of equipment or personnel.
Arena was used to simulate the can making and can filling lines to study the effect of changing the rate of the preventive maintenance on the daily production of the lines.
Page | 261
Problem Formulation System entities Can Making Line: The entities of this line are the boxes that contain the tin sheets. Every day, two boxes containing 1300 sheets each, with 28 cans of size 400 g produced from each sheet, are processed. Can Filling Line: The different products were split into separate categories. Products of the same category undergo the exact same processes, with the only difference being the sauces used. However, the model was not affected by this because one or two workers come two hours prior to production hours to heat the holding tank and mix the sauce. Therefore, the entities are the number of boxes ordered (each box contains 24 cans).
Page | 262
Material handling system Material handling is an activity that uses the right method to provide the right amount of the right material at the right place, at the right time, in the right sequence, in the right position and at the right cost. Material handling for the can making line is as follows:
Conveyer Belt: The belt transports 160 welded blanks per minute to the lacquering machine.
Magnetic Belt: In the curing process, 160 welded blanks are moved per minute to the flanging machine by the magnetic belt. The varnish is cured and dried during this process.
Palletizer: Every 2940 cans are put in a pallet, (14 layers with 210 cans in each layer) and moved by a forklift to the empty can storage area.
The material handling for the filling line consists of:
Bucket elevator: All the solid material (depending on the demand) is transported to the blancher by this elevator.
Inspection belt: All the solid material (depending on the demand) is sorted manually to remove any dark or broken pieces.
Crate: Crate holding 720 cans (split into 6 layers) are loaded to the sterilizing stage then unloaded to the labeler.
Forklift: Every 90 cartons are put in a pallet by two workers before being transported by a single forklift.
Page | 263
Current Problems in the Layout In the current layout, both lines are physically connected and the empty cans are supposed to go to the filling line through this link automatically once they are manufactured. However, this link is not being utilized, with the empty cans being transported manually to the filling line, instead. The cans are then palletized before they are filled. The reasons behind not using this connection are:
The difference in production plans of both lines.
Some of the empty cans might be defective and thus cannot be filled.
The factory has to work overtime to meet demand.
Also, the failure rates of the machines are high because the machines are very old. Therefore, the production lines are stopped in every breakdown. This will cause a delay meaning the factory will not meet deadlines or work overtime to do so.
Work Schedule In our model we have a total of 4 workers and their schedule is: 26 days/month 5 days/week 1 shift/day 10 hours/shift
Workers have breaks from 8-9 AM and 12-1:30 PM. All machines in the model are used for 10 hours.
Page | 264
Scrap Estimate In the can making line, only 0.15% of the total cans produced are defective per day. See Appendix (B) for details.
Policies The factory has some policies related to processing the entities and they are: The factory does not process the order as it is placed; but wait for other orders to come before processing them together. They store two containers for prime items and fill them again once they are used.
Page | 265
Simplification Assumptions In this section we will list the assumptions we used to simplify the model Can Making Line Assumptions:
Lids already fed in the seamer.
Overtime is not included.
Setup times and warming up time are done outside of production hours.
Can Filling Line Assumptions: The entities are the number of cartons ordered from the following categories: Fava beans, Peas, Chick peas, Beans, Mushroom, and Corn.
The soaking step is not considered since it is done overnight and is finished before production starts at 6:30 AM.
Reel washing, De-stoning, Blanching, and Inspection belt are considered as one process and are called the Process Line.
The rate of the process line is equivalent to 120 cans/minute.
Empty cans are ready to be filled.
Overtime is not included.
Soaking and mixing in the holding tank is done outside of production hours.
Setup times and warming up time are done outside of production hours.
Page | 266
Coding the Arena Model of the As-Is System Can Making line
Create 2
Proc es s 8
As s ign 1
Dis pos e 5
As s ign 2
0 N.Create 2 TBA : -0.5+LOGN(4.28,7.15) day Entity per arrival =1
0 N. process0 8 Delay Delay: constant=1hr
Variable 1=IRF(Slitter)==1 Variable 2=IRF(Welder)==1 Variable 3=IRF(Lacquering machine)==1 Variable 4=IRF(Curing machine)==1 Variable 5=IRF(Flanger)==1 Variable 6=IRF(Seamer)==1
Variable 1=IRF(Slitter)==0 Variable 2=IRF(Welder)==0 Variable 3=IRF(Lacquering machine)==0 Variable 4=IRF(Curing machine)==0 Variable 5=IRF(Flanger)==0 Variable 6=IRF(Seamer)==0
0 Create 1
Separate 1 O r iginal
Slitting
0 N.Create 1 TBA :constant=1 day Entity per arrival =ANINT(DISC(0.18,1,0.94,2,1,3))
0
Welding
Lac quering
N.Separate 1 Type: dublicate
N.Slitting 0 S-D-R Res:slitter , Q=1 Delay: constant=7.2 sec
Size:1299
N.Wedling 0 S-D-R Res:welder,Q=1 Delay: constant=10.5 sec
N.Lacquring 0 S-D-R Res:lacquering machine,Q=1 Delay: constant=10.5 sec
Daily Produc tion
0 Seaming
Separate 2 O r iginal
0 N.Seaming S-D-R Res:Seamer, Q=1 Delay: constant 10.5 sec
0 N.Separate 2 Type: dublicate Size:27
Curing
Flanging
Duplicat e
0 D ecide 1
0
N.Flanging 0 S-D-R Res:flanger ,Q=1 Delay: constant=10.5 sec
Dis pos e 3
0
Tr ue
2 way by chance 99.85%
Duplicat e
N.Curing S-D-R 0 Res:curing machine,Q=1 Delay: constant=10.5 sec
N.Daily Production Type: count Value=1
False
Sc rap
Dis pos e 4
0 N.Scrap Type: count Value=1
No. of replication:10 Rep. length:10 hours Hours / day:24
Page | 267
Figure 12: Arena model code of the can production line.
Explanation of the As-is Model of the Can Making Line As mentioned in the problem formulation section, the entities here are the boxes that contain the sheet metals. One, two, or three boxes/day are processed according to demand which follows the distribution ANINT(DISC(0.18, 1, 0.94, 2, 1, 3) (See Appendix (B) for more details). Each box contains 1300 sheets, with each sheet capable of producing 28 cans. First, the box arrives to the line. Then the module “separate” was used to convert the box to 1300 sheets. Note that the process time per sheet (per 28 cans) was used because the process time per can would be too small. The sheet is then cut to the desired length by the slitter before it goes to the welding machine to be welded, to the lacquering machine to add the varnish in the inner face, to the curing machine to cure the varnish, to the flanger to flange both ends and finally to the seamer to seam the lid onto one end. The process time from the welding machine to the seamer is constant at 10.5 seconds/sheet. Again, the separate module was used to convert one sheet into 28 cans. In the decide module the scrap rate of this line, which is 0.15% of the total production, was added. Finally, empty cans are palletized are transported to the storage area. The failure of the can making line was also modeled, where the mean time between failures follows the distribution -0.5 + LOGN(4.28, 7.15) (See Appendix (H) for more details).
Page | 268
Can Filling line N.Fava Beans Att, type=1
TBA : 0.5 + 8 * BETA(0.568, 1.52) days
Fa v a Be ans
Entity per arrival =ANINT(50 +
As s ig n 1
Att,proctime=52
0
2.83e+003 * BETA(0.577, 0.802))
Att, type=2 N.Chickpeas
Att,proctime=52
TBA : 0.5 + WEIB(1.95, 1.33) days
Ch ic k pe as
Entity per arrival =anint(470 +
As s ig n 2
0
Att, type=3
2.59e+003 * BETA(0.889, 0.774))
Att,proctime=27
N.peas TBA :
Pe as
Att, First item= tupe
As s ig n 3
Var, Switch=0
0.5 + WEIB(2.7, 1.5)days
0
Entity per arrival =anint(UNIF(50,
0
2.31e+003)) N.Corn TBA :
D ecide 2
Tr ue
As s ig n 7 2 way by condition
Co rn
As s ig n 4
UNIF(1.5, 17.5)days
Att, type=4
0
Entity per arrival =anint(TRIA(103,
Att,proctime=27
0
Fals e
2 way by condition
IF(first item == following item)
IF(switch == following item)
0 D ecide 3
188, 957))
Tr ue
PL
FS
N.Mushroom TBA : 0.5 + EXPO(7.05) days
N.PL
M us h roo m
Entity per arrival
As s ig n 5
0
Att, type=5
As s ig n 8
0
Att, Following item= tupe Var,Switch=1
N.Beans
0 9 N.Process
N.FS
0
Be an s
S-D-R
Res:Process line , Q=1
Res:Filler Seamers , Q=1
Delay:
Delay:
constant=12 sec
constant=10.3 sec
Delay: constant=30 min
As s ig n 6 Att, type=6
0
Att,proctime=45
3.1e+003 * BETA(0.603, 1.26))
Page | 269 Figure 13: Arena model code of the can filling line – Part 1.
0
S-D-R
Delay
TBA :
Entity per arrival =anint(79 +
Proc e s s 9
Att,proctime=30
=anint(NORM(412, 230))
0.5 + 7 * BETA(0.827, 2.05) days
Fals e
Coding
S terillizing
Crate Loading
0 N.Coding
0 N.Crate Loading
N.Sterilizing 0
S-D-R
Type: Temporary
S-D-R
Res:Coding machine,Q=1
Size:30
Res:Retort,Q=1 Delay: expression=proctime min
Delay: 10.3 sec
N.Labeling S-D-R
2 way by chance
Res:Labeller,Q=1
95.8%
Delay: constant=10.3 sec
0
0 Crate Unloading
S eparate 1
Decide 1
Labeling
T ru e
S hrink W rapping
daily production
Dispose 2
0 0
N.Crate Unloading S-D-R Res:Crate Unloader,Q=1
N.Separate 1
0
0
Type: Split Exiting
Fa ls e
0 N.Shrink Wrapping S-D-R
Batch
Res:Shrink Wrapper,Q=1
Delay: constant=5 Min
N.Daily Production Type: count Value=1
Delay: constant=10.3 sec
scrap
N.Scrap
variable , switch=1
No. of replication:32
Type: count
Warm-up:2 hours
Value=1
Rep. length:10 hours Hours / day:24
Figure 14: Arena model code of the can filling line – Part 2.
Page | 270
Explanation of the As-is Model of the Can Filling Line Entities were split into six categories (fava beans, chickpeas, peas, corn, mushroom, beans); all the products which have the same properties (eg: process time) were put in the same group. Each group belonged to the same create with TBA that represents the demand in days and with entities per arrival that represents the number of cartons (see Appendix (E) and Appendix (F) for more details about the distributions). An assign for each category was used to assign the type needed for the flag, as is explained later, and for assigning the process time that is needed for sterilizing. The flag: A decide module was added to check if the system variable changed or not (since a variable called switch=1 was identified). Therefore, it allows the entities with the same type to pass together with same variable value. Then a second decide module was added to check the type; so the first type will pass and the next one will be delayed for 30 min during which the line is cleaned. The entity will pass through a process called “process line” which takes 12 sec for each carton, then through the fillers and seamer which takes 10.3 for each carton. Finally, coding has the same process time for each carton. After that a batch module was added to load every 30 cartons in the same crate. The crate then goes to the sterilizing process, whose process time depends on the type of the product identified in the assign module, as afore-mentioned. Afterwards, the crate will be unloaded and this process will take 5 min/crate. A separate module is used for this purpose. Each carton will then pass through the labeler, which takes 10.3 sec, and a decide module is added to return the scrapped cans to the labeler to be relabeled. Finally, every two cartons will be packed together using the shrink wrapper machine which takes 10.3 sec and a counter is added to count the daily production in cartons.
Page | 271
Modeling the failures of the machines was done as follows: Resource module: Table 4.29: Summary of the resource module.
Resource
Failure
Failure Rule
Process Line
Failure 1
Preempt
Fillers and seamers
Failure 2
Preempt
Retort
Failure 3
Preempt
Labeller
Failure 4
Preempt
Shrink Wrapper
Failure 5
Preempt
Failure module: Table 4.30: Summary of failure module.
Name
Up time (days)
Down time (min)
Failure 1
EXPO(7.87)
30
Failure 2
EXPO (5.5)
60
Failure 3
EXPO(18.3)
30
Failure 4
EXPO (7.05)
60
Failure 5
EXPO (14.499)
60
Page | 272
Verification and Validation Can Making Line The Arena model that was coded for the can making line was verified and it was observed that the model works properly. Validating the daily production: The replication parameters are: Replication Length: 10 hours/day. Number of replications: 33 (see Appendix (I) for more details about the sample size).
For validation, the following two performance measures were used: The daily production. The scrap cans.
Page | 273
Validating the Daily Production: Since the daily production is normally distributed for both the real system and the asis model, see Appendix (C), hypothesis tests were applied to find the confidence intervals.
Table 4.31: Real system and as-is model statistics summary.
Real system
As-is model1
n
53
33
𝐱 (cans)
69,147.4
63,879.45
S (cans)
18,289.5
15,817.06
Testing the equality of two variances: H0: 𝜎12= 𝜎22 H1: 𝜎12≠ 𝜎22 Test Statistic: f0 Decision Rule: Reject Ho if f0> f α/2, n1-1, n2-1 Significance: α= 0.05 f0= 1.337 f0.025, 52, 32 =1.65 p-value = 0.383 Since f0< f0.025, 52, 32, H0 was not rejected and both variances are equal.
1
See Appendix (J) for more details
Page | 274
Testing the equality of two means:
H0: μ1= µ2 H1: μ1≠ µ2 Test Statistic: t0 Significance Level: α= 0.05 Decision Rule: Reject H0 if | t0|> t α/2, n1+n2-2 or p-value < α t0 = 1.413 p-value= 0.162 Since p-value > α. H0 was not rejected and both means are equal.
Confidence interval 𝑥1-𝑥2 - t α/2,v
𝑆12 𝑛1
𝑆2
𝑆12
2
𝑛1
+ 𝑛2 ≤ µ1- µ2 ≤ 𝑥1-𝑥2 + t α/2,v
𝑆2
+ 𝑛2
2
-2,156.64≤ µ1- µ2 ≤ 12,692.54 There is a 95% chance that the difference between the two means is within [2,156.64, 12,692.54]. Since zero is within this interval, both means are equal. The power of this test is 90%. Thus, the model is valid.
Page | 275
Validating the Daily Scrap Since the daily scrap is normally distributed for both the real system and the as-is model, see Appendix (C), hypothesis tests can be applied to find the confidence intervals. Table 4.32: Real system and as-is model statistics summary.
As-is model1
Real system n
53
33
𝐱 (cans)
97.94
96.56
S (cans)
34.09
25
Testing the equality of two variances: H0: 𝜎12= 𝜎22 H1: 𝜎12≠ 𝜎22 Test Statistic: f0 Decision Rule: Reject Ho if f0> f α/2, n1-1, n2-1 Significance: α= 0.05 f0 = 1.86 f0.025, 53, 32 = 1.65 p-value = 0.064 Since f0< f0.025, 52, 32, H0 was not rejected and both variances are equal.
1
See Appendix (J) for more details
Page | 276
Testing the equality of two means: H0: μ1= µ2 H1: μ1≠ µ2 Test Statistic: t0 Significance Level: α= 0.05 Decision Rule: Reject H0 if | t0|> t α/2, n1+n2-2 or P-value < α t0 = 0.217 df = 82.06 P-value = 0.829 Since p-value > α, H0 was not rejected and both variances are equal. Confidence interval: 𝑥1-𝑥2 - t α/2,v
𝑆12 𝑛1
𝑆2
𝑆12
2
𝑛1
+ 𝑛2 ≤ µ1- µ2 ≤ 𝑥1-𝑥2 + t α/2,v
𝑆2
+ 𝑛2
2
-11.34 ≤ µ1- µ2 ≤ 14.10 There is a 95% chance that the difference between the two means is within [-11.34, 14.10]. Since zero is within this interval, both means are equal. The power of this test is 90%. Thus, the model is valid.
Page | 277
Can Filling Line The Arena model that was coded for the can filling line was verified and it was observed that the model works properly. Validating the daily production: The replication parameters are: Replication Length: 10 hours/day. Number of replications: 32 (see Appendix (I) for more details about the sample size).
For validation, the daily production was used as a performance measure.
Page | 278
Validating the Daily Production: Since the daily production is normally distributed for both the real system and the asis model, see Appendix (C), hypothesis tests were applied to find the confidence intervals.
Table 4.33: Real system and as-is model statistics summary.
Real system
As-is model
N
58
32
𝐱 (carton)
2,338.1
2364.375
S (carton)
599.1
99.18
Testing the equality of two variances: H0: 𝜎12= 𝜎22 H1: 𝜎12≠ 𝜎22 Test Statistic: f0 Decision Rule: Reject Ho if f0> f α/2, n1-1, n2-1 Significance: α= 0.05 f0 = 36.49 f0.025, 57, 31 = 1.95 p-value = 1.071*10-17 Since f0> f0.025, 57, 31, H0 was rejected and there the variances are not equal.
Page | 279
Testing the equality of two means:
H0: μ 1= µ2 H1: μ1≠ µ2 Test Statistic: t0 Significance Level: α= 0.05 Decision Rule: Reject H0 if | t0|> t α/2, v or p-value < α t0 = -0.362 p-value= 0.746 Since p-value > α, H0 was not rejected and both means are equal. Confidence interval: 𝑥1-𝑥2 - t α/2,v
𝑆12 𝑛1
𝑆2
𝑆12
2
𝑛1
+ 𝑛2 ≤ µ1- µ2 ≤ 𝑥1-𝑥2 + t α/2,v
𝑆2
+ 𝑛2
2
-187.36 ≤ µ1- µ2 ≤ 134.81 There is a 95% chance that the difference between the two means is between [187.36, 134.81]. Since zero is within this interval, both means are equal. The power of this test is 90%. Thus, the model is valid.
Page | 280
4.17 Analysis of Daily Production Runs and Improvement
In this section, the statistical analysis used to compare between the daily production of each alternative and the as-is model, based on the simulation models, is shown.
Can Making Line For the can making line, only the most common case (2 boxes of sheet metal per day) was simulated to reduce the variability in the output. Alternative 1 The same Arena code of the can making line that was described in section 20.1 was run but with the new values of the mean time between failures obtained from alternative 1.
1
Table 4. 34: As-is model and alternative 1 statistics summary .
As-is model
Alternative 1
N
33
33
𝐱 (carton)
72,691.06
72,691.06
S (carton)
2.086
2.086
Testing the equality of two variances: H0: 𝜎12= 𝜎22 H1: 𝜎12≠ 𝜎22 Test Statistic: f0 Decision Rule: Reject Ho if p-value< α Significance: α= 0.05 f0= 1
1
See Appendix (J) for more details
Page | 281
p-value = 1 Since p-value> α, H0 was not rejected and both variances are equal.
Testing the equality of two means: H0: μ 1= µ2 H1: μ1≠ µ2 Test Statistic: t0 Significance Level: α= 0.05 Decision Rule: Reject H0 if | t0|> t α/2, v or p-value < α t0 = 0 p-value= 1 Since p-value > α, H0 was not rejected and both means are equal.
Confidence interval: 𝑥2-𝑥1 - t α/2,v
𝑆12 𝑛1
𝑆2
𝑆12
2
𝑛1
+ 𝑛2 ≤ µ2- µ1 ≤ 𝑥2-𝑥1 + t α/2,v
𝑆2
+ 𝑛2
2
-1.03 ≤ µ2- µ1 ≤ -1.03 There is a 95% chance that there is no significant difference between the as-is model and alternative 1. Thus, there is no improvement. The power of this test is 90%.
Page | 282
Alternative 2 The same Arena code of the can making line that was described in section 20.1 was used but with the new values of the mean time between failures obtained from alternative 2.
1
Table 4. 35: As-is model and alternative 2 statistics summary .
As-is model
Alternative 2
N
33
33
𝐱 (carton)
72,691.06
72,691.06
S (carton)
2.086
2.086
Testing the equality of two variances: H0: 𝜎12= 𝜎22 H1: 𝜎12≠ 𝜎22 Test Statistic: f0 Decision Rule: Reject Ho if p-value< α Significance: α= 0.05 f0= 1 p-value = 1 Since p-value> α, H0 is not rejected and both variances are equal.
1
See Appendix (J) for more details
Page | 283
Testing the equality of two means: H0: μ 1= µ2 H1: μ1≠ µ2 Test Statistic: t0 Significance Level: α= 0.05 Decision Rule: Reject H0 if | t0|> t α/2, v or p-value < α t0 = 0 p-value= 1 Since p-value > α, H0 is not rejected and both means are equal.
Confidence interval: 𝑥2-𝑥1 - t α/2,v
𝑆12 𝑛1
𝑆2
𝑆12
2
𝑛1
+ 𝑛2 ≤ µ2- µ1 ≤ 𝑥2-𝑥1 + t α/2,v
𝑆2
+ 𝑛2
2
-1.03 ≤ µ2- µ1 ≤ -1.03 There is a 95% chance that there is no significant difference between the as-is model and alternative 2. Thus, there is no improvement. The power of this test is 90%.
Page | 284
Alternative 3 The same Arena code of the can making line that was described in section 20.1 was used but with the new values of the mean time between failures obtained from alternative 3.
1
Table 4. 36: As-is model and alternative 3 statistics summary .
As-is model
Alternative 3
N
33
33
𝐱 (carton)
72,691.06
72,691.06
S (carton)
2.086
2.086
Testing the equality of two variances: H0: 𝜎12= 𝜎22 H1: 𝜎12≠ 𝜎22 Test Statistic: f0 Decision Rule: Reject Ho if p-value< α Significance: α= 0.05 f0= 1 p-value = 1 Since p-value> α, H0 was not rejected and both variances are equal.
1
See Appendix (J) for more details
Page | 285
Testing the equality of two means: H0: μ 1= µ2 H1: μ1≠ µ2 Test Statistic: t0 Significance Level: α= 0.05 Decision Rule: Reject H0 if | t0|> t α/2, v or p-value < α t0 = 0 p-value= 1 Since p-value > α, H0 was not rejected and both means are equal. Confidence interval: 𝑥2-𝑥1 - t α/2,v
𝑆12 𝑛1
𝑆2
𝑆12
2
𝑛1
+ 𝑛2 ≤ µ2- µ1 ≤ 𝑥2-𝑥1 + t α/2,v
𝑆2
+ 𝑛2
2
-1.03 ≤ µ2- µ1 ≤ -1.03 There is a 95% chance that there is no significant difference between the as-is model and alternative 3. Thus, there is no improvement. The power of the test is 90%.
Page | 286
Can Filling Line Alternative 1 The same Arena code of the can making line that was described in section 20.2 was used but with the new values of the mean time between failures obtained from alternative 1.
Table 4. 37: Summary of failure module of alternative 1.
Name
Up time (days)
Down time (min)
Failure 1
EXPO (11.24)
30
Failure 2
EXPO (6.99)
60
Failure 3
EXPO (62.5)
30
Failure 4
EXPO (9.71)
60
Failure 5
EXPO (32.26)
60
1
Table 4. 38: As-is model and alternative 1 statistics summary .
1
As-is model
Alternative 1
N
32
32
𝐱 (carton)
2,364.375
2,403.438
S (carton)
99.18433
88.25145
See Appendix (K) for more details
Page | 287
Testing the equality of two variances: H0: 𝜎12= 𝜎22 H1: 𝜎12≠ 𝜎22 Test Statistic: f0 Decision Rule: Reject Ho if p-value< α Significance: α= 0.05 p-value = 0.51 Since p-value> α, H0 was not rejected and both variances are equal.
Testing the equality of two means:
H0: μ 1= µ2 H1: μ1≠ µ2 Test Statistic: t0 Significance Level: α= 0.05 Decision Rule: Reject H0 if | t0|> t α/2, v or p-value < α t0 = -1.69 p-value= 0.095 Since p-value > α, H0 was not rejected and both means are equal.
Page | 288
Confidence interval: 𝑥2-𝑥1 - t α/2,v
𝑆12 𝑛1
𝑆2
𝑆12
2
𝑛1
+ 𝑛2 ≤ µ2- µ1 ≤ 𝑥2-𝑥1 + t α/2,v
𝑆2
+ 𝑛2
2
-7.86 ≤ µ2- µ1 ≤ 85.99 There is a 95% chance that the difference between the two means is within [-7.86, 85.99]. Since zero is within this interval then both means are equal. Thus, there is no improvement. The power of this test is 90%.
Page | 289
Alternative 2 The same Arena code of the can making line that was described in section 20.2 was used but with the new values of the mean time between failures obtained from alternative 2.
Table 4. 39: Summary of failure module of alternative 2.
Name
Up time (days)
Down time (min)
Failure 1
EXPO (11.24)
30
Failure 2
EXPO (50)
60
Failure 3
EXPO (62.5)
30
Failure 4
EXPO (9.71)
60
Failure 5
EXPO (32.26)
60
1
Table 4. 40: As-is model and alternative 1 statistics summary .
1
As-is model
Alternative 2
N
32
32
𝐱 (carton)
2,364.375
2,426.281
S (carton)
99.18433
60.79221
See Appendix (K) for more details
Page | 290
Testing the equality of two variances: H0: 𝜎12= 𝜎22 H1: 𝜎12≠ 𝜎22 Test Statistic: f0 Decision Rule: Reject Ho if p-value< α Significance: α= 0.05 f0= 2.66 p-value = 7.02E-03 Since p-value< α, H0 was rejected and the variances are not equal.
Testing the equality of two means: H0: μ 1= µ2 H1: μ1≠ µ2 Test Statistic: t0 Significance Level: α= 0.05 Decision Rule: Reject H0 if | t0|> t α/2, v or p-value < α t0 = -3.05 p-value= 3.5E-03 Since p-value < α, H0 is not rejected and the means are not equal.
Page | 291
Confidence interval: 𝑥2-𝑥1 - t α/2,v
𝑆12 𝑛1
𝑆2
𝑆12
2
𝑛1
+ 𝑛2 ≤ µ2- µ1 ≤ 𝑥2-𝑥1 + t α/2,v
𝑆2
+ 𝑛2
2
20.63 ≤ µ2- µ1 ≤ 103.18 There is a 95% chance that the difference between the two means is within [20.63, 103.18] and the mean of alternative 2 is always greater than the mean of the as-is model. Thus, there is an improvement. The power of this test is 90%. From the above confidence interval, it can be concluded that by applying the maintenance plan of alternative 2, the factory can increase production by 21 to 103 cartons daily. This translates a reduction in overtime hours and cost by 3.51-17.22%.
Page | 292
Alternative 3 The same Arena code of the can making line that was described in section 20.2 was used but with the new values of the mean time between failures obtained from alternative 3.
Table 4. 41: Summary of failure module of alternative 3.
Name
Up time (days)
Down time (min)
Failure 1
EXPO (27.15)
30
Failure 2
EXPO (28.49)
60
Failure 3
EXPO (26.20)
30
Failure 4
EXPO (28.27)
60
Failure 5
EXPO (26.33)
60
1
Table 4. 42: As-is model and alternative 1 statistics summary .
1
As-is model
Alternative 3
n
32
32
𝐱 (carton)
2,364.375
2,438.875
S (carton)
99.18433
51.271
See Appendix (K) for more details
Page | 293
Testing the equality of two variances: H0: 𝜎12= 𝜎22 H1: 𝜎12≠ 𝜎22 Test Statistic: f0 Decision Rule: Reject Ho if p-value< α Significance: α= 0.05 f0= 3.74 p-value = 3.4E-04 Since p-value< α, H0 was rejected and the variances are not equal.
Testing the equality of two means: H0: μ 1= µ2 H1: μ1≠ µ2 Test Statistic: t0 Significance Level: α= 0.05 Decision Rule: Reject H0 if | t0|> t α/2, v or p-value < α t0 = -3.83 p-value= 3.68E-04 Since p-value < α, H0 was rejected and the means are not equal.
Page | 294
Confidence interval: 𝑥2-𝑥1 - t α/2,v
𝑆12 𝑛1
𝑆2
𝑆12
2
𝑛1
+ 𝑛2 ≤ µ2- µ1 ≤ 𝑥2-𝑥1 + t α/2,v
𝑆2
+ 𝑛2
2
34.78 ≤ µ2- µ1 ≤ 114.22 There is a 95% confident that the difference between the two means is within [34.78, 114.22] and the mean of alternative 3 is always greater than the mean of the as-is model. Thus, there is an improvement. The power of this test is 90%. From the above confidence interval, it is concluded that by applying the maintenance plan of alternative 3, the factory can increase production by 35 to 114 cartons daily. This translates to a reduction in overtime hours and cost of 5.85-19.06%.
Page | 295
4.18 Summary of the Proposed Alternatives
After analyzing each alternative and comparing it to the as-is situation; the reduction in maintenance cost and the increase in both reliability and daily production for both lines, under each alternative, are summarized in the following table. Table 4. 43: Summary of proposed alternatives.
Criteria
Alternative 1
Alternative 2
Alternative 3
Maintenance Cost
-29%
-61.8%
-72.65%
+3.91%
+17.53%
+19.82%
+26.65%
+43.24%
+38.19%
No improvement
No improvement
No improvement
No improvement
+0.89 to +4.36%
+1.48 to +4.82%
No improvement
-3.51 to -17.22%
-5.85 to -19.06%
Reliability of Can Making Line Reliability of Filling Line Daily Production of Can Making Line Daily Production of Filling Line Overtime cost
As shown, alternative 3 is the best in all criteria.
Page | 296
4.18 Conclusion
The maintenance policies that the factory currently applies were studied and both the reliability and the maintenance cost were calculated. Then, the as-is system was simulated using Arena software under the current operational conditions and failure rates. Moreover, new maintenance policies were proposed to reduce the failure rates of the machines, the reliability and the maintenance cost were calculated for each alternative. The new policies were then simulated and compared with the as-is model and the best policy was selected based on the following criteria: highest increase in the reliability and production rate, and greatest reduction in the maintenance cost.
Page | 297
Page | 298
5. Inventory Management and Production Planning
Page | 299
Page | 300
5.1 Introduction
The National Canned Food Company produces a variety of canned foods produced based on demand. The lead time between placing an order and receiving it is 21 days. This period is set to ensure the availability of the relevant raw materials. In addition to its factory in Subhan, the company has a warehouse in Kabd for packing material, as well as a warehouse for exported goods located in Mina Abdullah. The factory has three raw material inventories. One is for labels (including can labels and special offers labels), spices inventory (for example, sugar and salt) and can plant inventory (such as copper wires and glue). The final product inventory has a capacity of 100,000 cans.
Figure 5.15: Inventory flow in the factory.
Problem description Page | 301
The company cannot meet the demand on time due to poor production plans.
Some processes take longer due to poor planning.
Excessive inventory is held in the system.
Lead time is relatively long for the final product.
Solution approach 1. Demand was forecasted for all 27 types of goods produced using past data. 2. The current production capacity was calculated
to determine if
demand can comfortably be covered. 3. Inventory plans were developed for raw material and production plans for finished products.
Methodology 1. Collected data for past three years for all goods. 2. Applied forecasting methods to determine the demand for the next year. 3. Selected best forecasting method. 4. Analyzed the current inventory system and order quantities for raw material. 5. Applied inventory models to determine optimum order quantities and compare with the current system. 6. Analyzed current production plan and lot sizes 7. Applied production planning models and determined optimum lot sizes for all products. 8. Checked the production capacity and matched it with the plan. 9. Adjusted capacity according to the demand. 10. Applied service level calculation to determine safety stock.
5.2 Analysis
Page | 302
1- Demand forecasting Demand forecasting is the activity of estimating the demand of products that consumers will purchase in the future. It involves techniques such as methods that can be used to predict the future demands or sales. Forecasting depends on the trend of the historical data ,and the company’s demand of the final products have a trend and seasonality in every September of each year, considering year (2006-2007-2008) . In our project the demand was forecasted for the next five years for capacity planning but only the demand forecasted of year 2009 was used for production planning. The appropriated method that will apply to forecast must be with least error after testing the MAD (Mean Absolute Deviation) from each method. The tested forecasting methods are:
Moving average method
Exponential smoothing with trend method
Regression method
Winter’s method
Holt’s method
In our project Holt's Method has the least error, therefore it was used. Page | 303
Holt’s method This method is designed to track time series with linear trend. Two smoothing constant α and β must be specified for two smoothing equations. The equations are: St * = (α)*(Dt*) + (1-α)*(St-1* + Gt-1) Gt* = (β)*(St* - St-1*) + (1-β)*(Gt-1*) St-1* = Dt-1* Gt-1* = (Di* - Dj*) / (i – j) Ft,t+τ * =St* + τGt* Ft = Ft* (CQt*) Where St * is the value of the intercept, Gt* is the value of the slope, Ft* symbolizes the forecast of the deseasonalized unit and F t is the final forecast of the original units. To compute the value of Gt-1*, an approximate trend line should be obtained by eyeballing the data. The first point the trend line through is the value of ( i ) and the last point is the value of ( j ).
Baked Beans Page | 304
Table 5.1: The data of Avg. MA (12) and Ct for beaked beans.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
9330
Feb-06
9087
Mar-06
8481
Apr-06
9208
May-06
8724
Jun-06
9572
Jul-06
10299
10135.790
1.016
Aug-06
12480
10212.526
1.222
Sep-06
15751
10285.729
1.531
Oct-06
10299
10359.437
0.994
Nov-06
9208
10434.154
0.883
Dec-06
8724
10510.385
0.830
Jan-07
10263
10593.180
0.969
Feb-07
9996
10688.091
0.935
Mar-07
9330
10805.720
0.863
Apr-07
10129
10914.262
0.928
May-07
9596
10995.542
0.873
Jun-07
10529
11070.259
0.951
Jul-07
11329
11145.481
1.016
Aug-07
13728
11222.218
1.223
Sep-07
17326
11295.421
1.534
Oct-07
11329
11369.128
0.996
Nov-07
10129
11443.845
0.885
Dec-07
9596
11520.077
0.833
Jan-08
11195
11602.872
0.965
Page | 305
Feb-08
10905
11697.783
0.932
Mar-08
10178
11815.412
0.861
Apr-08
11050
11923.954
0.927
May-08
10468
12005.234
0.872
Jun-08
11486
12079.951
0.951
Jul-08
12359
Aug-08
14976
Sep-08
18901
Oct-08
12359
Nov-08
11050
Dec-08
10468
Baked Beans
Figure 5.2: Forecasting model for seasonality & trend for baked beans.
Page | 306
As mentioned previously the value of Gt-1* can only be determined if a trend line passing through the deseasonalized demand is drawn. The trend line passes through D10* and D30* which are the values of (i) and (j) respectively. All the forecasting data can be seen in Appendix O (D10* is 10344). Different values of α and β were generated. It happens to be that when α is 0.9 and β is 0.1, the error is at its minimum.
Baked Beans
Figure 5.3: Forecasted demand for baked beans.
From the figure 5.3 above, it can be seen that the forecasted demand is almost overlapping the actual demand. This indicates that the error is very low. After applying Holt's method, the following results were achieved: Mean Absolute Deviation = 12.542 Mean Square Error = 385.972 The following figures and tables pertain to the remaining products which were dealt with in exactly the same manner as the baked beans.
Page | 307
Black Eye Beans Table 5.2. The data of Avg. MA (12) and Ct for black eye beans.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
1323
Feb-06
1289
Mar-06
1203
Apr-06
1306
May-06
1237
Jun-06
1358
Jul-06
1461
1437.597
1.016
Aug-06
1770
1448.481
1.222
Sep-06
2234
1458.863
1.531
Oct-06
1461
1469.318
0.994
Nov-06
1306
1479.915
0.883
Dec-06
1237
1490.727
0.830
Jan-07
1456
1502.470
0.969
Feb-07
1418
1515.932
0.935
Mar-07
1323
1532.616
0.863
Apr-07
1437
1548.010
0.928
May-07
1361
1559.539
0.873
Jun-07
1493
1570.136
0.951
Jul-07
1607
1580.805
1.016
Aug-07
1947
1591.689
1.223
Sep-07
2457
1602.072
1.534
Oct-07
1607
1612.526
0.996
Nov-07
1437
1623.123
0.885
Dec-07
1361
1633.935
0.833
Page | 308
Jan-08
1588
1645.679
0.965
Feb-08
1547
1659.140
0.932
Mar-08
1444
1675.824
0.861
Apr-08
1567
1691.219
0.927
May-08
1485
1702.747
0.872
Jun-08
1629
1713.345
0.951
Jul-08
1753
Aug-08
2124
Sep-08
2681
Oct-08
1753
Nov-08
1567
Dec-08
1485
Black Eye Beans
Figure 5.4: Forecasting model for seasonality & trend for black eye beans.
It can clearly be seen in figure 5.4 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 1467 and 1713, respectively.
Page | 309
Black Eye Beans
Figure 5.5: Forecasted demand for balck eye beans.
The error, as shown below, is quite low. This indicates that the forecasting method used is applicable. Mean Absolute Deviation = 1.779 Mean Square Error = 7.765
Page | 310
Broad Beans Table 5.3: The data of Avg. MA (12) and Ct for broad beans.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
13234
Feb-06
12890
Mar-06
12031
Apr-06
13062
May-06
12375
Jun-06
13578
Jul-06
14609
14377.893
1.016
Aug-06
17703
14486.745
1.222
Sep-06
22343
14590.585
1.531
Oct-06
14609
14695.142
0.994
Nov-06
13062
14801.130
0.883
Dec-06
12375
14909.267
0.830
Jan-07
14558
15026.713
0.969
Feb-07
14180
15161.347
0.935
Mar-07
13234
15328.207
0.863
Apr-07
14369
15482.177
0.928
May-07
13612
15597.475
0.873
Jun-07
14936
15703.463
0.951
Jul-07
16070
15810.168
1.016
Aug-07
19473
15919.020
1.223
Sep-07
24578
16022.860
1.534
Oct-07
16070
16127.417
0.996
Nov-07
14369
16233.405
0.885
Dec-07
13612
16341.542
0.833
Page | 311
Jan-08
15881
16458.988
0.965
Feb-08
15469
16593.622
0.932
Mar-08
14437
16760.482
0.861
Apr-08
15675
16914.452
0.927
May-08
14850
17029.750
0.872
Jun-08
16294
17135.738
0.951
Jul-08
17531
Aug-08
21244
Sep-08
26812
Oct-08
17531
Nov-08
15675
Dec-08
14850
Broad Beans
Figure 5.6: Forecasting model for seasonality & trend for broad beans.
It can clearly be seen in figure 5.6 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 14673 and 17127, respectively.
Page | 312
Broad Beans
Figure 5.7: Forecasted demand.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 17.791 Mean Square Error = 776.660
Page | 313
4. Chick Peas Table 5.4: The data of Avg. MA (12) and Ct for chick peas.
Time
Demand (Dt)
Jan-06
17595
Feb-06
17138
Mar-06
15996
Apr-06
17367
May-06
16453
Jun-06
18052
Jul-06
Avg.MA(12)
Index (Ct)
19423
19115.814
1.016
Aug-06
23537
19260.537
1.222
Sep-06
29706
19398.595
1.531
Oct-06
19423
19537.605
0.994
Nov-06
17367
19678.520
0.883
Dec-06
16453
19822.290
0.830
Jan-07
19355
19978.439
0.969
Feb-07
18852
20157.438
0.935
Mar-07
17595
20379.284
0.863
Apr-07
19103
20583.990
0.928
May-07
18098
20737.283
0.873
Jun-07
19858
20878.197
0.951
Jul-07
21366
21020.064
1.016
Aug-07
25890
21164.787
1.223
Sep-07
32677
21302.845
1.534
Oct-07
21366
21441.855
0.996
Nov-07
19103
21582.770
0.885
Dec-07
18098
21726.540
0.833 Page | 314
Jan-08
21114
21882.689
0.965
Feb-08
20566
22061.688
0.932
Mar-08
19195
22283.534
0.861
Apr-08
20840
22488.240
0.927
May-08
19743
22641.533
0.872
Jun-08
21663
22782.447
0.951
Jul-08
23308
Aug-08
28244
Sep-08
35648
Oct-08
23308
Nov-08
20840
Dec-08
19743
Chick Peas
Figure 5.8: Forecasting model for seasonality & trend for chick peas.
It can clearly be seen in figure 5.8 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 19508 and 22771, respectively.
Page | 315
Chick Peas
Figure 5.9: Forecasted demand for chick peas.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 23.654 Mean Square Error = 1372.860
Page | 316
5. Chick Peas 10mm Table 5.5: The data of Avg. MA (12) and Ct. for chick peas 10 mm.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
2290
Feb-06
2230
Mar-06
2082
Apr-06
2260
May-06
2141
Jun-06
2349
Jul-06
2528
2487.708
1.016
Aug-06
3063
2506.542
1.222
Sep-06
3866
2524.508
1.531
Oct-06
2528
2542.599
0.994
Nov-06
2260
2560.937
0.883
Dec-06
2141
2579.648
0.830
Jan-07
2519
2599.969
0.969
Feb-07
2453
2623.263
0.935
Mar-07
2290
2652.134
0.863
Apr-07
2486
2678.774
0.928
May-07
2355
2698.724
0.873
Jun-07
2584
2717.062
0.951
Jul-07
2781
2735.524
1.016
Aug-07
3369
2754.358
1.223
Sep-07
4253
2772.325
1.534
Oct-07
2781
2790.416
0.996
Nov-07
2486
2808.754
0.885
Dec-07
2355
2827.464
0.833
Page | 317
Jan-08
2748
2847.785
0.965
Feb-08
2676
2871.080
0.932
Mar-08
2498
2899.951
0.861
Apr-08
2712
2926.591
0.927
May-08
2569
2946.540
0.872
Jun-08
2819
2964.879
0.951
Jul-08
3033
2859.3087
Aug-08
3676
Sep-08
4639
Oct-08
3033
Nov-08
2712
Dec-08
2569
Chick Peas 10mm
Figure 5.10: Forecasting model for seasonality & trend for chick peas 10mm.
It can clearly be seen in figure 5.10 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 2539 and 2963, respectively.
Page | 318
Chick Peas 10mm
Figure 5.11: Forecasted demand for chick peas 10mm.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 3.078 Mean Square Error = 23.251
Page | 319
6. Chick Peas with Chili Table 5.6: The data of Avg. MA (12) and Ct for chick peas with chilli.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
123
Feb-06
120
Mar-06
112
Apr-06
122
May-06
115
Jun-06
126
Jul-06
136
133.847
1.016
Aug-06
165
134.860
1.222
Sep-06
208
135.827
1.531
Oct-06
136
136.800
0.994
Nov-06
122
137.787
0.883
Dec-06
115
138.793
0.830
Jan-07
136
139.887
0.969
Feb-07
132
141.140
0.935
Mar-07
123
142.693
0.863
Apr-07
134
144.127
0.928
May-07
127
145.200
0.873
Jun-07
139
146.187
0.951
Jul-07
150
147.180
1.016
Aug-07
181
148.193
1.223
Sep-07
229
149.160
1.534
Oct-07
150
150.133
0.996
Nov-07
134
151.120
0.885
Dec-07
127
152.127
0.833
Page | 320
Jan-08
148
153.220
0.965
Feb-08
144
154.473
0.932
Mar-08
134
156.027
0.861
Apr-08
146
157.460
0.927
May-08
138
158.533
0.872
Jun-08
152
159.520
0.951
Jul-08
163
Aug-08
198
Sep-08
250
Oct-08
163
Nov-08
146
Dec-08
138
ilihC htiw saeP kcihC
Figure 5.12: Forecasting model for seasonality & trend for chick peas with chili.
It can clearly be seen in figure 5.12 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 137 and 159, respectively.
Page | 321
ilihC htiw saeP kcihC
Figure 5.13: Forecasted demand for chick peas with chili.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 0.166 Mean Square Error = 0.067
Page | 322
7. Fava Beans Table 5.7: The data of Avg. MA (12) and Ct for fava beans.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
14129
Feb-06
13762
Mar-06
12845
Apr-06
13946
May-06
13212
Jun-06
14496
Jul-06
15597
15350.121
1.016
Aug-06
18900
15466.335
1.222
Sep-06
23854
15577.196
1.531
Oct-06
15597
15688.823
0.994
Nov-06
13946
15801.978
0.883
Dec-06
13212
15917.427
0.830
Jan-07
15542
16042.815
0.969
Feb-07
15138
16186.553
0.935
Mar-07
14129
16364.696
0.863
Apr-07
15340
16529.077
0.928
May-07
14533
16652.171
0.873
Jun-07
15946
16765.327
0.951
Jul-07
17157
16879.246
1.016
Aug-07
20790
16995.460
1.223
Sep-07
26240
17106.321
1.534
Oct-07
17157
17217.948
0.996
Nov-07
15340
17331.103
0.885
Dec-07
14533
17446.552
0.833
Page | 323
Jan-08
16955
17571.940
0.965
Feb-08
16515
17715.678
0.932
Mar-08
15414
17893.821
0.861
Apr-08
16735
18058.202
0.927
May-08
15854
18181.296
0.872
Jun-08
17395
18294.452
0.951
Jul-08
18716
Aug-08
22680
Sep-08
28625
Oct-08
18716
Nov-08
16735
Dec-08
15854
snaeB avaF
Figure 5.14: Forecasting model for seasonality & trend for fava beans.
It can clearly be seen in figure 5.14 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 15665 and 18286, respectively.
Page | 324
snaeB avaF
Figure 5.15: Forecasted demand for fava beans.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 18.994 Mean Square Error = 885.247
Page | 325
8. Fava Beans with Chili Table 5.8: The data of Avg. MA (12) and Ct for fava beans with chili.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
179
Feb-06
174
Mar-06
163
Apr-06
177
May-06
167
Jun-06
184
Jul-06
198
194.496
1.016
Aug-06
239
195.968
1.222
Sep-06
302
197.373
1.531
Oct-06
198
198.788
0.994
Nov-06
177
200.221
0.883
Dec-06
167
201.684
0.830
Jan-07
197
203.273
0.969
Feb-07
192
205.094
0.935
Mar-07
179
207.351
0.863
Apr-07
194
209.434
0.928
May-07
184
210.994
0.873
Jun-07
202
212.428
0.951
Jul-07
217
213.871
1.016
Aug-07
263
215.343
1.223
Sep-07
332
216.748
1.534
Oct-07
217
218.163
0.996
Nov-07
194
219.596
0.885
Dec-07
184
221.059
0.833 Page | 326
Jan-08
215
222.648
0.965
Feb-08
209
224.469
0.932
Mar-08
195
226.726
0.861
Apr-08
212
228.809
0.927
May-08
201
230.369
0.872
Jun-08
220
231.803
0.951
Jul-08
237
Aug-08
287
Sep-08
363
Oct-08
237
Nov-08
212
Dec-08
201
ilihC htiw snaeB avaF
Figure 5.16: Forecasting model for seasonality & trend for fava beans with chili.
It can clearly be seen in figure 5.16 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 198 and 232, respectively.
Page | 327
ilihC htiw snaeB avaF
Figure 5.17: Forecasted demand for fava beans with chili.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 0.241 Mean Square Error = 0.142
Page | 328
9. Egyptian Foul Medames Table 5.9: The data of Avg. MA (12) and Ct for foul medames - Egyptian.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
1686
Feb-06
1642
Mar-06
1533
Apr-06
1664
May-06
1576
Jun-06
1730
Jul-06
1861
1831.608
1.016
Aug-06
2255
1845.475
1.222
Sep-06
2846
1858.703
1.531
Oct-06
1861
1872.023
0.994
Nov-06
1664
1885.524
0.883
Dec-06
1576
1899.300
0.830
Jan-07
1855
1914.262
0.969
Feb-07
1806
1931.413
0.935
Mar-07
1686
1952.669
0.863
Apr-07
1830
1972.283
0.928
May-07
1734
1986.971
0.873
Jun-07
1903
2000.473
0.951
Jul-07
2047
2014.066
1.016
Aug-07
2481
2027.933
1.223
Sep-07
3131
2041.161
1.534
Oct-07
2047
2054.481
0.996
Nov-07
1830
2067.983
0.885
Dec-07
1734
2081.758
0.833
Page | 329
Jan-08
2023
2096.720
0.965
Feb-08
1971
2113.871
0.932
Mar-08
1839
2135.127
0.861
Apr-08
1997
2154.742
0.927
May-08
1892
2169.430
0.872
Jun-08
2076
2182.932
0.951
Jul-08
2233
Aug-08
2706
Sep-08
3416
Oct-08
2233
Nov-08
1997
Dec-08
1892
semadeM luoF naitpygE
Figure 5.18: Forecasting model for seasonality & trend for foul medames - Egyptain.
It can clearly be seen in figure 5.18 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 1869 and 2182, respectively.
Page | 330
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 2.266 Mean Square Error = 12.604
10. Saudi Foul Medames Table 5.10: The data of Avg. MA (12) and Ct Saudi Foul Medames.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
100
Feb-06
98
Mar-06
91
Apr-06
99
May-06
94
Jun-06
103
Jul-06
111
109.169
1.016
Aug-06
134
109.995
1.222
Sep-06
170
110.784
1.531
Oct-06
111
111.578
0.994
Nov-06
99
112.382
0.883
Dec-06
94
113.203
0.830
Jan-07
111
114.095
0.969
Feb-07
108
115.117
0.935
Mar-07
100
116.384
0.863
Apr-07
109
117.553
0.928
May-07
103
118.429
0.873
Jun-07
113
119.234
0.951
Jul-07
122
120.044
1.016
Aug-07
148
120.870
1.223
Page | 331
Sep-07
187
121.659
1.534
Oct-07
122
122.453
0.996
Nov-07
109
123.257
0.885
Dec-07
103
124.078
0.833
Jan-08
121
124.970
0.965
Feb-08
117
125.992
0.932
Mar-08
110
127.259
0.861
Apr-08
119
128.428
0.927
May-08
113
129.304
0.872
Jun-08
124
130.109
0.951
Jul-08
133
Aug-08
161
Sep-08
204
Oct-08
133
Nov-08
119
Dec-08
113
Saudi Foul Medames
Figure 5.20: Forecasting model for seasonality & trend for Saudi Foul Medames.
Page | 332
It can clearly be seen in figure 5.20 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 111 and 130, respectively.
Saudi Foul Medames
Figure 5.21: Forecasted demand for Saudi Foul Medames.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 570.825 Mean Square Error = 338502.937
Page | 333
11. Lebanese Foul Medames Table 5.11: The data of Avg. MA (12) and Ct for Lebanese foul medames.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
540
Feb-06
526
Mar-06
491
Apr-06
533
May-06
505
Jun-06
554
Jul-06
596
586.667
1.016
Aug-06
722
591.108
1.222
Sep-06
912
595.345
1.531
Oct-06
596
599.612
0.994
Nov-06
533
603.936
0.883
Dec-06
505
608.349
0.830
Jan-07
594
613.141
0.969
Feb-07
579
618.634
0.935
Mar-07
540
625.443
0.863
Apr-07
586
631.725
0.928
May-07
555
636.430
0.873
Jun-07
609
640.754
0.951
Jul-07
656
645.108
1.016
Aug-07
795
649.550
1.223
Sep-07
1003
653.787
1.534
Oct-07
656
658.053
0.996
Nov-07
586
662.378
0.885
Dec-07
555
666.790
0.833
Page | 334
Jan-08
648
671.582
0.965
Feb-08
631
677.076
0.932
Mar-08
589
683.884
0.861
Apr-08
640
690.167
0.927
May-08
606
694.871
0.872
Jun-08
665
699.196
0.951
Jul-08
715
Aug-08
867
Sep-08
1094
Oct-08
715
Nov-08
640
Dec-08
606
Lebanese Foul Medames
Figure5.22: Forecasting model for seasonality & trend for Lebanese foul medames.
It can clearly be seen in figure 5.22 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 599 and 699, respectively.
Page | 335
Lebanese Foul Medames
Figure 5.23: Forecasted demand for Lebanese foul medames.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 0.726 Mean Square Error = 1.293
Page | 336
12. Green Peas Table 5.12: The data of Avg. MA (12) and Ct for green peas.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
19444
Feb-06
18939
Mar-06
17677
Apr-06
19192
May-06
18182
Jun-06
19949
Jul-06
21465
21124.768
1.016
Aug-06
26010
21284.701
1.222
Sep-06
32828
21437.268
1.531
Oct-06
21465
21590.888
0.994
Nov-06
19192
21746.611
0.883
Dec-06
18182
21905.492
0.830
Jan-07
21389
22078.050
0.969
Feb-07
20833
22275.862
0.935
Mar-07
19444
22521.021
0.863
Apr-07
21111
22747.242
0.928
May-07
20000
22916.644
0.873
Jun-07
21944
23072.368
0.951
Jul-07
23611
23229.143
1.016
Aug-07
28611
23389.076
1.223
Sep-07
36111
23541.643
1.534
Oct-07
23611
23695.263
0.996
Nov-07
21111
23850.986
0.885
Dec-07
20000
24009.867
0.833
Page | 337
Jan-08
23333
24182.425
0.965
Feb-08
22727
24380.237
0.932
Mar-08
21212
24625.396
0.861
Apr-08
23030
24851.617
0.927
May-08
21818
25021.019
0.872
Jun-08
23939
25176.743
0.951
Jul-08
25758
Aug-08
31212
Sep-08
39394
Oct-08
25758
Nov-08
23030
Dec-08
21818
Green Peas
Figure 5.24: Forecasting model for seasonality & trend for green peas.
It can clearly be seen in figure 5.24 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 21559 and 25165, respectively.
Page | 338
Green Peas
Figure 5.25: Forecasted demand.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 26.140 Mean Square Error = 1676.581
Page | 339
13. Hummus Tahineh - Chick Peas 7 mm Table 5.13: The data of Avg. MA (12) and Ct for Hummus Tahineh - Chick Peas 7 mm.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
10494
Feb-06
10221
Mar-06
9540
Apr-06
10358
May-06
9813
Jun-06
10767
Jul-06
11584
11400.808
1.016
Aug-06
14037
11487.122
1.222
Sep-06
17717
11569.461
1.531
Oct-06
11584
11652.368
0.994
Nov-06
10358
11736.410
0.883
Dec-06
9813
11822.156
0.830
Jan-07
11543
11915.284
0.969
Feb-07
11244
12022.041
0.935
Mar-07
10494
12154.351
0.863
Apr-07
11393
12276.439
0.928
May-07
10794
12367.864
0.873
Jun-07
11843
12451.906
0.951
Jul-07
12743
12536.516
1.016
Aug-07
15441
12622.830
1.223
Sep-07
19489
12705.169
1.534
Oct-07
12743
12788.076
0.996
Nov-07
11393
12872.118
0.885
Dec-07
10794
12957.864
0.833
Page | 340
Jan-08
12593
13050.992
0.965
Feb-08
12266
13157.749
0.932
Mar-08
11448
13290.059
0.861
Apr-08
12429
13412.148
0.927
May-08
11775
13503.572
0.872
Jun-08
12920
13587.615
0.951
Jul-08
13901
Aug-08
16845
Sep-08
21260
Oct-08
13901
Nov-08
12429
Dec-08
11775
Hummus Tahineh - Chick Peas 7 mm
Figure 5.26: Forecasting model for seasonality & trend for Hummus Tahineh - Chick Peas 7 mm.
It can clearly be seen in figure 5.26 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 11635 and 13581, respectively.
Page | 341
Hummus Tahineh - Chick Peas 7 mm
Figure 5.27: Forecasted demand for Hummus Tahineh - Chick Peas 7 mm.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 14.107 Mean Square Error = 488.328
Page | 342
14. Hummus Tahineh with Garlic Table 5.14: The data of Avg. MA (12) and Ct for Hummus Tahineh with Garlic.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
72
Feb-06
70
Mar-06
66
Apr-06
71
May-06
68
Jun-06
74
Jul-06
80
78.468
1.016
Aug-06
97
79.062
1.222
Sep-06
122
79.628
1.531
Oct-06
80
80.199
0.994
Nov-06
71
80.777
0.883
Dec-06
68
81.368
0.830
Jan-07
79
82.009
0.969
Feb-07
77
82.743
0.935
Mar-07
72
83.654
0.863
Apr-07
78
84.494
0.928
May-07
74
85.124
0.873
Jun-07
82
85.702
0.951
Jul-07
88
86.284
1.016
Aug-07
106
86.878
1.223
Sep-07
134
87.445
1.534
Oct-07
88
88.016
0.996
Nov-07
78
88.594
0.885
Dec-07
74
89.184
0.833
Page | 343
Jan-08
87
89.825
0.965
Feb-08
84
90.560
0.932
Mar-08
79
91.471
0.861
Apr-08
86
92.311
0.927
May-08
81
92.940
0.872
Jun-08
89
93.519
0.951
Jul-08
96
Aug-08
116
Sep-08
146
Oct-08
96
Nov-08
86
Dec-08
81
Hummus Tahineh with Garlic
Figure 5.28: Forecasting model for seasonality & trend for Hummus Tahineh with Garlic.
It can clearly be seen in figure 5.28 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 80 and 93,
respectively.
Page | 344
Hummus Tahineh with Garlic
Figure 5.29: Forecasted demand for Hummus Tahineh with Garlic.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 0.097 Mean Square Error = 0.023
Page | 345
15. Hotdog Sausage Table 5.15: The data of Avg. MA (12) and Ct for hotdog sausage.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
63
Feb-06
61
Mar-06
57
Apr-06
62
May-06
59
Jun-06
64
Jul-06
69
68.011
1.016
Aug-06
84
68.526
1.222
Sep-06
106
69.017
1.531
Oct-06
69
69.512
0.994
Nov-06
62
70.013
0.883
Dec-06
59
70.524
0.830
Jan-07
69
71.080
0.969
Feb-07
67
71.717
0.935
Mar-07
63
72.506
0.863
Apr-07
68
73.234
0.928
May-07
64
73.780
0.873
Jun-07
71
74.281
0.951
Jul-07
76
74.786
1.016
Aug-07
92
75.301
1.223
Sep-07
116
75.792
1.534
Oct-07
76
76.287
0.996
Nov-07
68
76.788
0.885
Dec-07
64
77.299
0.833
Page | 346
Jan-08
75
77.855
0.965
Feb-08
73
78.492
0.932
Mar-08
68
79.281
0.861
Apr-08
74
80.009
0.927
May-08
70
80.555
0.872
Jun-08
77
81.056
0.951
Jul-08
83
Aug-08
100
Sep-08
127
Oct-08
83
Nov-08
74
Dec-08
70
Hotdog Sausage
Figure 5.30: Forecasting model for seasonality & trend for hotdog sausage.
From It can clearly be seen in figure 5.30 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 69 and 81, respectively.
Page | 347
Hotdog Sausage
Figure 5.31: Forecasted demand for hotdog sausage.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 0.084 Mean Square Error =0.017
Page | 348
16. Frankfurter Sausage Table 5.16: The data of Avg. MA (12) and Ct for frankfurter sausage.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
103
Feb-06
100
Mar-06
94
Apr-06
102
May-06
96
Jun-06
106
Jul-06
114
111.929
1.016
Aug-06
138
112.777
1.222
Sep-06
174
113.585
1.531
Oct-06
114
114.399
0.994
Nov-06
102
115.224
0.883
Dec-06
96
116.066
0.830
Jan-07
113
116.980
0.969
Feb-07
110
118.028
0.935
Mar-07
103
119.327
0.863
Apr-07
112
120.526
0.928
May-07
106
121.424
0.873
Jun-07
116
122.249
0.951
Jul-07
125
123.079
1.016
Aug-07
152
123.927
1.223
Sep-07
191
124.735
1.534
Oct-07
125
125.549
0.996
Nov-07
112
126.374
0.885
Dec-07
106
127.216
0.833
Page | 349
Jan-08
124
128.130
0.965
Feb-08
120
129.178
0.932
Mar-08
112
130.477
0.861
Apr-08
122
131.676
0.927
May-08
116
132.574
0.872
Jun-08
127
133.399
0.951
Jul-08
136
Aug-08
165
Sep-08
209
Oct-08
136
Nov-08
122
Dec-08
116
Frankfurter Sausage
Figure 5.32: Forecasting model for seasonality & trend for frankfurter sausage.
It can clearly be seen in figure 5.32 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 114 and 133, respectively.
Page | 350
Frankfurter Sausage
Figure 5.33: Forecasted demand for frankfurter sausage.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 0.139 Mean Square Error = 0.047
Page | 351
17. Cocktail Sausage Table 5.17: The data of Avg. MA (12) and Ct for cocktail sausage.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
283
Feb-06
276
Mar-06
257
Apr-06
279
May-06
265
Jun-06
290
Jul-06
312
307.429
1.016
Aug-06
379
309.757
1.222
Sep-06
478
311.977
1.531
Oct-06
312
314.213
0.994
Nov-06
279
316.479
0.883
Dec-06
265
318.791
0.830
Jan-07
311
321.302
0.969
Feb-07
303
324.181
0.935
Mar-07
283
327.749
0.863
Apr-07
307
331.041
0.928
May-07
291
333.506
0.873
Jun-07
319
335.773
0.951
Jul-07
344
338.054
1.016
Aug-07
416
340.382
1.223
Sep-07
526
342.602
1.534
Oct-07
344
344.838
0.996
Nov-07
307
347.104
0.885
Dec-07
291
349.416
0.833
Page | 352
Jan-08
340
351.927
0.965
Feb-08
331
354.806
0.932
Mar-08
309
358.374
0.861
Apr-08
335
361.666
0.927
May-08
318
364.131
0.872
Jun-08
348
366.398
0.951
Jul-08
375
Aug-08
454
Sep-08
573
Oct-08
375
Nov-08
335
Dec-08
318
Cocktail Sausage
Figure 5.34: Forecasting model for seasonality & trend for cocktail sausage.
It can clearly be seen in figure 5.34 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 314 and 366, respectively.
Page | 353
Cocktail Sausage
Figure 5.35: Forecasted demand for cocktail sausage.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 0.380 Mean Square Error = 0.355
Page | 354
18. Lima Beans Table 5.18: The data of Avg. MA (12) and Ct for lima beans.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
253
Feb-06
246
Mar-06
230
Apr-06
249
May-06
236
Jun-06
259
Jul-06
279
274.386
1.016
Aug-06
338
276.463
1.222
Sep-06
426
278.445
1.531
Oct-06
279
280.440
0.994
Nov-06
249
282.463
0.883
Dec-06
236
284.526
0.830
Jan-07
278
286.768
0.969
Feb-07
271
289.337
0.935
Mar-07
253
292.521
0.863
Apr-07
274
295.460
0.928
May-07
260
297.660
0.873
Jun-07
285
299.683
0.951
Jul-07
307
301.719
1.016
Aug-07
372
303.796
1.223
Sep-07
469
305.778
1.534
Oct-07
307
307.773
0.996
Nov-07
274
309.796
0.885
Dec-07
260
311.860
0.833
Page | 355
Jan-08
303
314.101
0.965
Feb-08
295
316.670
0.932
Mar-08
276
319.855
0.861
Apr-08
299
322.793
0.927
May-08
283
324.993
0.872
Jun-08
311
327.016
0.951
Jul-08
335
Aug-08
405
Sep-08
512
Oct-08
335
Nov-08
299
Dec-08
283
Lima Beans
Figure 5.36: Forecasting model for seasonality & trend for lima beans.
It can clearly be seen in figure 5.36 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 280 and 327, respectively.
Page | 356
Lima Beans
Figure 5.37: Forecasted demand for lima beans.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 0.340 Mean Square Error = 0.283
Page | 357
19. Mixed Vegetables Table 5.19: The data of Avg. MA (12) and Ct for mixed vegetables.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
941
Feb-06
917
Mar-06
855
Apr-06
929
May-06
880
Jun-06
965
Jul-06
1039
1022.254
1.016
Aug-06
1259
1029.993
1.222
Sep-06
1589
1037.376
1.531
Oct-06
1039
1044.810
0.994
Nov-06
929
1052.346
0.883
Dec-06
880
1060.034
0.830
Jan-07
1035
1068.384
0.969
Feb-07
1008
1077.957
0.935
Mar-07
941
1089.820
0.863
Apr-07
1022
1100.767
0.928
May-07
968
1108.965
0.873
Jun-07
1062
1116.501
0.951
Jul-07
1143
1124.087
1.016
Aug-07
1385
1131.827
1.223
Sep-07
1747
1139.210
1.534
Oct-07
1143
1146.643
0.996
Nov-07
1022
1154.179
0.885
Dec-07
968
1161.867
0.833
Page | 358
Jan-08
1129
1170.218
0.965
Feb-08
1100
1179.790
0.932
Mar-08
1026
1191.654
0.861
Apr-08
1114
1202.601
0.927
May-08
1056
1210.798
0.872
Jun-08
1158
1218.334
0.951
Jul-08
1246
Aug-08
1510
Sep-08
1906
Oct-08
1246
Nov-08
1114
Dec-08
1056
Mixed Vegetables
Figure 5.38: Forecasting model for seasonality & trend for mixed vegetables.
It can clearly be seen in figure 5.38 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 1043 and 1218, respectively.
Page | 359
Mixed Vegetables
Figure 5.39 Forecasted demand for mixed vegetables.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 1.265 Mean Square Error = 3.926
Page | 360
20. Mushroom Pieces and Stems Table 5.20: The data of Avg. MA (12) and Ct for mushroom pieces and stems.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
488
Feb-06
475
Mar-06
444
Apr-06
482
May-06
456
Jun-06
501
Jul-06
539
530.200
1.016
Aug-06
653
534.214
1.222
Sep-06
824
538.043
1.531
Oct-06
539
541.899
0.994
Nov-06
482
545.807
0.883
Dec-06
456
549.795
0.830
Jan-07
537
554.126
0.969
Feb-07
523
559.091
0.935
Mar-07
488
565.244
0.863
Apr-07
530
570.922
0.928
May-07
502
575.174
0.873
Jun-07
551
579.082
0.951
Jul-07
593
583.017
1.016
Aug-07
718
587.031
1.223
Sep-07
906
590.860
1.534
Oct-07
593
594.716
0.996
Nov-07
530
598.624
0.885
Page | 361
Dec-07
502
602.612
0.833
Jan-08
586
606.943
0.965
Feb-08
570
611.907
0.932
Mar-08
532
618.061
0.861
Apr-08
578
623.738
0.927
May-08
548
627.990
0.872
Jun-08
601
631.899
0.951
Jul-08
646
Aug-08
783
Sep-08
989
Oct-08
646
Nov-08
578
Dec-08
548
Mushroom Pieces and Stems
Figure 5.40: Forecasting model for seasonality & trend for mushroom pieces and stems.
It can clearly be seen in figure 5.40 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 541 and 632, respectively.
Page | 362
Mushroom Pieces and Stems
Figure 5.41: Forecasted demand for mushroom pieces and stems.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 0.656 Mean Square Error = 1.056
Page | 363
21. Whole Mushrooms Table 5.21: The data of Avg. MA (12) and Ct for whole mushrooms.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
628
Feb-06
612
Mar-06
571
Apr-06
620
May-06
587
Jun-06
644
Jul-06
693
682.200
1.016
Aug-06
840
687.365
1.222
Sep-06
1060
692.292
1.531
Oct-06
693
697.253
0.994
Nov-06
620
702.281
0.883
Dec-06
587
707.412
0.830
Jan-07
691
712.985
0.969
Feb-07
673
719.373
0.935
Mar-07
628
727.290
0.863
Apr-07
682
734.596
0.928
May-07
646
740.066
0.873
Jun-07
709
745.095
0.951
Jul-07
762
750.158
1.016
Aug-07
924
755.323
1.223
Sep-07
1166
760.250
1.534
Oct-07
762
765.211
0.996
Nov-07
682
770.240
0.885
Dec-07
646
775.371
0.833
Page | 364
Jan-08
754
780.943
0.965
Feb-08
734
787.331
0.932
Mar-08
685
795.248
0.861
Apr-08
744
802.554
0.927
May-08
705
808.025
0.872
Jun-08
773
813.054
0.951
Jul-08
832
Aug-08
1008
Sep-08
1272
Oct-08
832
Nov-08
744
Dec-08
705
Whole Mushrooms
Figure 5.42: Forecasting model for seasonality & trend for whole mushrooms.
It can clearly be seen in figure 5.42 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 696 and 813, respectively.
Page | 365
Whole Mushrooms
Figure 5.43: Forecasted demand for whole mushrooms.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 0.844 Mean Square Error = 1.748
Page | 366
22. Peas and Carrots Table 5.22:The data of Avg. MA (12) and Ct for peas and carrots .
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
137
Feb-06
134
Mar-06
125
Apr-06
135
May-06
128
Jun-06
141
Jul-06
151
148.904
1.016
Aug-06
183
150.032
1.222
Sep-06
231
151.107
1.531
Oct-06
151
152.190
0.994
Nov-06
135
153.288
0.883
Dec-06
128
154.408
0.830
Jan-07
151
155.624
0.969
Feb-07
147
157.018
0.935
Mar-07
137
158.746
0.863
Apr-07
149
160.341
0.928
May-07
141
161.535
0.873
Jun-07
155
162.633
0.951
Jul-07
166
163.738
1.016
Aug-07
202
164.865
1.223
Sep-07
255
165.941
1.534
Oct-07
166
167.023
0.996
Nov-07
149
168.121
0.885
Dec-07
141
169.241
0.833
Page | 367
Jan-08
164
170.457
0.965
Feb-08
160
171.852
0.932
Mar-08
150
173.580
0.861
Apr-08
162
175.174
0.927
May-08
154
176.368
0.872
Jun-08
169
177.466
0.951
Jul-08
182
Aug-08
220
Sep-08
278
Oct-08
182
Nov-08
162
Dec-08
154
Peas and carrots
Figure 5.44: Forecasting model for seasonality & trend for peas and carrots.
It can clearly be seen in figure 5.44 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 152 and 177, respectively.
Page | 368
Peas and carrots
Figure 5.45: Forecasted demand for peas and carrots.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 0.184 Mean Square Error = 0.083
Page | 369
23. Peeled Fava Beans with Chilli Table 5.23: The data of Avg. MA (12) and Ct for peeled fava with chilli .
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
617
Feb-06
601
Mar-06
561
Apr-06
609
May-06
577
Jun-06
633
Jul-06
682
670.739
1.016
Aug-06
826
675.817
1.222
Sep-06
1042
680.661
1.531
Oct-06
682
685.539
0.994
Nov-06
609
690.483
0.883
Dec-06
577
695.528
0.830
Jan-07
679
701.007
0.969
Feb-07
661
707.288
0.935
Mar-07
617
715.072
0.863
Apr-07
670
722.255
0.928
May-07
635
727.634
0.873
Jun-07
697
732.578
0.951
Jul-07
750
737.556
1.016
Aug-07
908
742.634
1.223
Sep-07
1147
747.478
1.534
Oct-07
750
752.356
0.996
Nov-07
670
757.300
0.885
Dec-07
635
762.345
0.833
Page | 370
Jan-08
741
767.824
0.965
Feb-08
722
774.104
0.932
Mar-08
674
781.889
0.861
Apr-08
731
789.071
0.927
May-08
693
794.450
0.872
Jun-08
760
799.395
0.951
Jul-08
818
Aug-08
991
Sep-08
1251
Oct-08
818
Nov-08
731
Dec-08
693
Peeled Fava Beans with Chili
Figure 5.46: Forecasting model for seasonality & trend for peeled fava beans with chili.
It can clearly be seen in figure 5.46 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 685 and 799, respectively
Page | 371
Peeled Fava Beans with Chilli
Figure 5.47: Forecasted demand for peeled fava beans with chili.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 0.830 Mean Square Error = 1.690
Page | 372
24. Red Kidney Beans Table 5.24: The data of Avg. MA (12) and Ct for red kidney beans.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
2067
Feb-06
2013
Mar-06
1879
Apr-06
2040
May-06
1932
Jun-06
2120
Jul-06
2281
2245.111
1.016
Aug-06
2764
2262.108
1.222
Sep-06
3489
2278.323
1.531
Oct-06
2281
2294.649
0.994
Nov-06
2040
2311.199
0.883
Dec-06
1932
2328.085
0.830
Jan-07
2273
2346.424
0.969
Feb-07
2214
2367.447
0.935
Mar-07
2067
2393.502
0.863
Apr-07
2244
2417.545
0.928
May-07
2126
2435.549
0.873
Jun-07
2332
2452.099
0.951
Jul-07
2509
2468.761
1.016
Aug-07
3041
2485.758
1.223
Sep-07
3838
2501.973
1.534
Oct-07
2509
2518.299
0.996
Nov-07
2244
2534.849
0.885
Dec-07
2126
2551.735
0.833
Page | 373
Jan-08
2480
2570.074
0.965
Feb-08
2415
2591.097
0.932
Mar-08
2254
2617.152
0.861
Apr-08
2448
2641.195
0.927
May-08
2319
2659.199
0.872
Jun-08
2544
2675.749
0.951
Jul-08
2737
Aug-08
3317
Sep-08
4187
Oct-08
2737
Nov-08
2448
Dec-08
2319
Red Kidney Beans
Figure 5.48: Forecasting model for seasonality & trend for red kidney beans.
It can clearly be seen in figure 5.48 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 2291 and 2674, respectively.
Page | 374
Red Kidney Beans
Figure 5.49: Forecasted demand for red kidney beans.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 2.778 Mean Square Error = 18.937
Page | 375
25. Red Kidney Beans with Chili Table 5.25: The data of Avg. MA (12) and Ct for red kidney beans with chili.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
58
Feb-06
56
Mar-06
53
Apr-06
57
May-06
54
Jun-06
59
Jul-06
64
62.741
1.016
Aug-06
77
63.216
1.222
Sep-06
98
63.669
1.531
Oct-06
64
64.125
0.994
Nov-06
57
64.588
0.883
Dec-06
54
65.059
0.830
Jan-07
64
65.572
0.969
Feb-07
62
66.159
0.935
Mar-07
58
66.888
0.863
Apr-07
63
67.559
0.928
May-07
59
68.063
0.873
Jun-07
65
68.525
0.951
Jul-07
70
68.991
1.016
Aug-07
85
69.466
1.223
Sep-07
107
69.919
1.534
Oct-07
70
70.375
0.996
Nov-07
63
70.838
0.885
Dec-07
59
71.309
0.833
Page | 376
Jan-08
69
71.822
0.965
Feb-08
68
72.409
0.932
Mar-08
63
73.138
0.861
Apr-08
68
73.809
0.927
May-08
65
74.313
0.872
Jun-08
71
74.775
0.951
Jul-08
77
Aug-08
93
Sep-08
117
Oct-08
77
Nov-08
68
Dec-08
65
Red Kidney Beans with Chili
Figure 5.50: Forecasting model for seasonality & trend for red kidney beans with chili.
It can clearly be seen in figure 5.50 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 64 and 75, respectively.
Page | 377
Red Kidney Beans with Chili
Figure 5.51: Forecasted demand for red kidney beans with chili.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 0.078 Mean Square Error = 0.015
Page | 378
26. Sweet Corn Table 5.26: The data of Avg. MA (12) and Ct for sweet corn.
Demand (Dt)
Avg.MA(12)
Index (Ct)
1863
1833.532
1.016
2258
1847.413
1.222
2849
1860.656
1.531
1863
1873.989
0.994
1666
1887.505
0.883
1578
1901.295
0.830
1856
1916.272
0.969
1808
1933.442
0.935
1688
1954.720
0.863
1832
1974.355
0.928
1736
1989.059
0.873
1905
2002.575
0.951
2049
2016.182
1.016
2483
2030.063
1.223
3134
2043.306
1.534
2049
2056.639
0.996
1832
2070.155
0.885
1736
2083.945
0.833
1688 1644 1534 1666 1578 1732
Page | 379
2025
2098.922
0.965
1973
2116.092
0.932
1841
2137.370
0.861
1999
2157.005
0.927
1894
2171.709
0.872
2078
2185.225
0.951
2236 2709 3419 2236 1999 1894
Sweet Corn
Figure 5.52: Forecasting model for seasonality & trend for sweet corn.
It can clearly be seen in figure 5.52 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 1871 and 2184, respectively
Page | 380
Sweet Corn
Figure 5.53: Forecasted demand for sweet corn.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 2.269 Mean Square Error = 12.630
Page | 381
27. White Beans Table 5.27: The data of Avg. MA (12) and Ct for white beans.
Time
Demand (Dt)
Avg.MA(12)
Index (Ct)
Jan-06
346
Feb-06
337
Mar-06
314
Apr-06
341
May-06
323
Jun-06
355
Jul-06
382
374.333
1.020
Aug-06
463
374.333
1.236
Sep-06
584
374.333
1.560
Oct-06
382
374.333
1.020
Nov-06
341
374.333
0.912
Dec-06
323
374.333
0.864
Jan-07
346
374.333
0.924
Feb-07
337
374.333
0.900
Mar-07
314
374.333
0.840
Apr-07
341
374.333
0.912
May-07
323
374.333
0.864
Jun-07
355
374.333
0.948
Jul-07
382
377.216
1.012
Aug-07
463
382.906
1.208
Sep-07
584
388.333
1.504
Oct-07
382
393.799
0.970
Nov-07
341
399.339
0.855
Dec-07
323
404.991
0.799
Page | 382
Jan-08
415
411.130
1.010
Feb-08
404
418.168
0.967
Mar-08
377
426.890
0.884
Apr-08
410
434.938
0.942
May-08
388
440.965
0.880
Jun-08
426
446.505
0.954
Jul-08
458
Aug-08
555
Sep-08
701
Oct-08
458
Nov-08
410
Dec-08
388
White Beans
Figure 5.54: Forecasting model for seasonality & trend for white beans.
It can clearly be seen in figure 5.54 above, that the trend line passes through points D10* and D30*. The values that correspond to D10* and D30* are 384 and 448,
respectively
Page | 383
White Beans
Figure 5.55: Forecasted demand for white beans.
After applying Holt's Method, the following results were obtained: Mean Absolute Deviation = 4.607 Mean Square Error = 119.103
Page | 384
Five Year Forecasts The following charts show the forecasted demands for the next five years for each type of product.
Baked Beans Baked Beans
Figure 5.56: Forecasted demand for baked beans.
2. Black Eye Beans
Black Eye Beans
Figure 5.57: Forecasted demand for black eye beans.
Page | 385
3. Broad Beans Broad Beans
Figure 5.58: Forecasted demand for broad beans.
4. Chick Peas Chick Peas
Figure 5.59: Forecasted demand for chick peas.
Page | 386
5. Chick Peas 10mm
Chick Peas 10mm
Figure 5.60: Forecasted demand for chick peas 10mm.
6. Chick Peas with Chili
Chick Peas with Chili
Figure 5.61: Forecasted demand for chick peas with chili.
Page | 387
7. Fava Beans
Fava Beans
Figure 5.62: Forecasted demand for fava beans.
8. Fava Beans with Chili
Fava Beans with Chili
Figure 5.63: Forecasted demand for fava beans with chili.
Page | 388
9. Egyptian Foul Medames Egyptian Foul Medames
Figure 5.64: Forecasted demand for Egyptian foul medames.
10. Saudi Foul Medames
Saudi Foul Medames
Figure 5.65: Forecasted demand for Saudi foul medames.
Page | 389
11. Lebanese Fould Medames
Lebanese Foul Medames
Figure 5.66: Forecasted demand for Lebanese foul medames.
12. Green Peas Green Peas
Figure 5.67: Forecasted demand for Green Peas.
Page | 390
13. Hummus Tahineh - Chick Peas 7mm Hummus Tahineh – Chick Peas 7mm
Figure 5.68: Forecasted demand for hummus tahineh – chick peas 7mm.
14. Hummus Tahineh with Garlic
Hummus Tahineh with Garlic
Figure 5.69: Forecasted demand for hummus tahineh with garlic.
Page | 391
15. Hotdog Sausage Hotdog Sausage
Figure 5.70: Forecasted demand for hotdog sausage.
16. Frankfurter Sausage Frankfurter Sausage
Figure 5.71: Forecasted demand for frankfurter sausage.
Page | 392
17. Cocktail Sausage
Cocktail Sausage
Figure 5.72: Forecasted demand for cocktail sausage.
18. Lima Beans Lima Beans
Figure 5.73: Forecasted demand for lima beans.
Page | 393
19. Mixed Vegetables Mixed Vegetables
Figure 5.74: Forecasted demand for mixed vegetables.
20. Mushroom Pieces and Stems
Mushroom Pieces and Stems
Figure 5.75: Forecasted demand for mushroom pieces and stems.
Page | 394
21. Whole Mushrooms Whole Mushrooms
Figure 5.76: Forecasted demand for whole mushrooms.
22. Peas and carrots
Peas and Carrots
Figure 5.77: Forecasted demand for peas and carrots.
Page | 395
23. Peeled Fava Beans with Chili Peeled Fava Beans with Chili
Figure 5.78: Forecasted demand for peeled fava beans with chili.
24. Red Kidney Beans
Red Kidney Beans
Figure 5.79: Forecasted demand for red kidney beans.
Page | 396
25. Red Kidney Beans with Chili Red Kidney Beans with Chili
Figure 5.80: Forecasted demand for red kidney beans with chili.
26. Sweet Corn
Sweet Corn
Figure 5.81: Forecasted demand for sweet corn.
Page | 397
27. White Beans White Beans
Figure 5.82: Forecasted demand for white beans.
Page | 398
Economic Order Quantity (EOQ) for Production Planning The EOQ is essentially an accounting formula that determines the point at which the combination of order costs and inventory carrying costs are the least. The result is the most cost effective quantity to order. In purchasing, this is known as the order quantity, whilst in manufacturing it is known as the production lot size. While EOQ may not apply to every inventory situation, most organizations will find it beneficial in at least some aspect of their operation.
Parameters: Q = Order quantity. Q * = Optimal order quantity. D = Annual demand quantity of the product (average demand for three years was used). P = Purchase cost per unit. C = A = Fixed cost per order. H= ht = total annual holding cost per unit (also known as carrying cost)/
Equations: TC = H Q/2 + A D/Q TC*= √ (2ADH) Q* = √ (2AD/H)
Page | 399
Table 5.28: The current and optimal quantities for the can plant.
Item
Unit
Q
Q*
Labels
CTN
2000
1474
Cooper Wire
K.G
4250
812
Lids
CTN
2000
1266
Tin-sheet
CTN
1000
847
Cartoon
CTN
1500
1030
Shrink Film
PCS
30000
26857
Glue
K.G
6751
3071
Lacquer
K.G
6179
1593
The optimal quantities (Q*) for each item of the can plant’s raw materials are less than the current quantities in the system. Table 5.29: The difference between the current total cost and the optimal total cost of the can plant.
Item
Unit
TC
TC*
TC-TC*
Labels
CTN
112
106
6
Cooper Wire
K.G
124
45
79
Lids
CTN
20
18
2
Tin-sheet
CTN
8
7
0
Cartoon
CTN
10
9
1
Shrink Film
PCS
8
7
0
Glue
K.G
60
44
16
Lacquer
K.G
75
36
39
Sum
143.58
After applying the EOQ model to the can plant raw materials, it was found that the optimal quantity saves a total of 143.58 KD/year.
Page | 400
Table 5.30: The current and optimal quantities for the spices.
Item
Unit
Q
Q*
Tomato Pasta
K.G
6000
3537
Lemon Juice
Ltr
500
339
Green Color
K.G
1000
405
Edta
K.G
1000
775
Citric Acid
K.G
3000
1960
Camon Powder
K.G
1000
596
Chick Peas Powder
K.G
2000
1695
Spices
K.G
1000
548
Whole Red Chili
K.G
500
381
Onion Powder
K.G
2000
706
Powder Red Chili
K.G
1200
1014
The optimal quantities (Q*) for each item of the spices raw material are less than the current quantities in the system.
Page | 401
Table 5.31: The difference between the current total cost and the optimal total cost of the spices.
Item
Unit
TC
TC*
TC-TC*
Tomato Pasta
K.G
40.0
34.49
5.51
Lemon Juice
Ltr
16.0
14.75
1.25
Green Color
K.G
48.0
33.37
14.63
Edta
K.G
12.0
11.62
0.38
Citric Acid
K.G
28.0
25.51
2.49
Camon Powder
K.G
16.0
13.42
2.58
Chick Peas Powder
K.G
17.0
16.52
0.48
Spices
K.G
20.0
16.43
3.57
Whole Red Chili
K.G
10.0
9.44
0.56
Onion Powder
K.G
38.0
23.81
14.14
Powder Red Chili
K.G
15.0
14.44
0.56
Sum=
46.1
After applying the EOQ model to the spices, it was found that the optimal quantities would save a total of 46.1 KD/year.
Page | 402
Table 5.32: The current and optimal quantities for the beans.
Item
Unit
Q
Q*
Black Eye Beans
K.G
10553
2096
Broad Beans
K.G
132234
17287
Chick Peas 8mm
K.G
101930
18899
Chick Peas 7mm
K.G
27500
4633
Chick Peas 10mm
K.G
46309
6619
Whole Mushrooms
K.G
18750
2972
Mushroom Stems and Pieces
K.G
18750
2412
Green Peas
K.G
61291
2419
Mixed Vegetables
K.G
25811
2013
Navy Beans
K.G
53905
5228
White Beans
K.G
18766
2499
Peeled Fava Beans
K.G
65000
11185
Fava Beans
K.G
71153
7396
Red Kidney
K.G
33869
2070
Sweet Corn
K.G
33572
5806
Lima Beans
K.G
19184
4229
Carrots
K.G
12000
4883
The optimal quantities (Q*) for each item of the beans raw material are less than the current quantities in the system.
Page | 403
Table 5.33: The difference between the current total cost and the optimal total cost of the beans.
Item
Unit
TC
TC*
TC-TC*
Black Eye Beans
K.G
75.44
42.44
33.01
Broad Beans
K.G
813.74
311.17
502.58
Chick Peas 8mm
K.G
643.12
340.18
302.93
Chick Peas 7mm
K.G
243.70
118.15
125.56
Chick Peas 10mm
K.G
322.16
134.04
188.12
Whole Mushrooms
K.G
291.85
133.72
158.12
Mushroom Stems and Pieces
K.G
288.23
108.53
179.70
Green Peas
K.G
261.10
30.84
230.26
Mixed Vegetables
K.G
240.93
55.85
185.08
Navy Beans
K.G
116.02
33.29
82.74
White Beans
K.G
269.71
104.95
164.76
Peeled Foul
K.G
594.01
293.61
300.41
Fava Beans
K.G
397.68
122.04
275.65
Red Kidney
K.G
263.42
48.03
215.39
Sweet Corn
K.G
289.39
143.69
145.71
Lima Beans
K.G
34.95
21.54
13.41
Carrots
K.G
13.96
13.65
0.31
Sum=
3101.73
After applying the EOQ model to the beans, the optimal quantity (Q*) for each was found to save a total of 3101.73 KD/year.
Page | 404
Economic Production Quantity (EPQ) for Production Planning The EPQ is a method used to determine the optimal procedure for producing multiple items in one system, to minimize the holding and the setup costs. This procedure helps to avoid stock outs in a production cycle.
Parameters: If (n) products are to be produced on a single machine: λi = Demand rate for product i. Pi = Production rate for product i. ht,i = Total holding cost per unit time of product i. Ki = Cost of setting up the production line to produce product i. K: Setup Cost = setup time *production rate*selling price The setup time for the 28 products is equal to 30 minutes each. Four workers conduct the setup but the cost of their labor was not considered because it is already considered in the selling price of each can. Assumptions required for satisfying the demand with current capacity: Feasibility: ∑λi/Pi ≤ 1. Utilization of the rotation cycle so that in each cycle, there is exactly one setup for each product. The products are produced in the same sequence in each production cycle. T = cycle time = √ ((2 ∑ Ki) / (hi * λi)) The setup time for each production type is not significant which will ensure that T ≥ (∑Si / 1- ∑ (λi/Pi)) = Tmin
Page | 405
The production rate 160 cans/min which is the maximum production rate The factory works 26 days per month and 12 hours per day to meet the customers demand which includes the overtime shifts. Table 5.34: Total holding cost.
Capital Cost (h0 = rv)
Storage (h1)
Insurance (h2)
Security (h3)
Total holding Cost (hT)
0.00219
0.005
0.003
0.004
0.01419
0.00208
0.005
0.003
0.004
0.01408
0.00169
0.005
0.003
0.004
0.01369
0.00141
0.005
0.003
0.004
0.01341
0.00186
0.005
0.003
0.004
0.01386
0.00242
0.005
0.003
0.004
0.01442
0.00146
0.005
0.003
0.004
0.01346
0.00169
0.005
0.003
0.004
0.01369
0.00276
0.005
0.003
0.004
0.01476
0.00219
0.005
0.003
0.004
0.01419
0.00264
0.005
0.003
0.004
0.01464
0.00129
0.005
0.003
0.004
0.01329
0.00242
0.005
0.003
0.004
0.01442
0.00283
0.005
0.003
0.004
0.01483
0.00416
0.005
0.003
0.004
0.01616
0.00630
0.005
0.003
0.004
0.01830
0.00450
0.005
0.003
0.004
0.01650
0.00495
0.005
0.003
0.004
0.01695
0.00276
0.005
0.003
0.004
0.01476
0.00585
0.005
0.003
0.004
0.01785 Page | 406
0.00585
0.005
0.003
0.004
0.01785
0.00321
0.005
0.003
0.004
0.01521
0.00203
0.005
0.003
0.004
0.01403
0.00225
0.005
0.003
0.004
0.01425
0.00180
0.005
0.003
0.004
0.01380
0.00327
0.005
0.003
0.004
0.01527
0.00420
0.005
0.003
0.004
0.01620
The set up cost (K) for all products is equal to 30 r is equal to 0.015 for all products Cycle time (T) is equal to 1.0524 for all products Tmin is equal to 0.8844 for all products
Page | 407
P/year
∆
h'=∆hT
λh'
T
Tmin
EPQ (Q*)
λ/P
Q
Tj
(Q*)
TVC(Q) TVC(Q*)
Q*-Q
Tj (Hrs)
Tj (Min)
TVC
Demand (λ)
1
13,154
166,400
0.9209
0.0131
171.95
0.91
0.3931
11,975
111
0.0791
3,500
136
0.072
24
8,475
29.94
1796
2
1,866
166,400
0.9888
0.0139
25.98
0.91
0.3931
1,698
45
0.0112
1,000
63
0.0102
18
698
4.25
255
3
18,660
166,400
0.8879
0.0122
226.77
0.91
0.3931
16,987
136
0.1121
3,500
181
0.1021
45
13,487
42.47
2548
4
24,809
166,400
0.8509
0.0114
283.01
0.91
0.3931
22,584
162
0.1491
3,500
233
0.1357
71
19,084
56.46
3388
5
24,809
166,400
0.8509
0.0118
292.51
0.91
0.3931
22,584
166
0.1491
3,500
233
0.1357
67
19,084
56.46
3388
6
174
166,400
0.999
0.0144
2.5
0.91
0.3931
158
34
0.001
500
14
0.001
20-
342-
0.4
24
7
19,922
166,400
0.8803
0.0119
236.09
0.91
0.3931
18,135
140
0.1197
3,500
191
0.109
51
14,635
45.34
2720
8
252
166,400
0.9985
0.0137
3.45
0.91
0.3931
230
35
0.0015
500
19
0.0014
16-
270-
0.57
34
9
2,377
166,400
0.9857
0.0145
34.58
0.91
0.3931
2,164
49
0.0143
1,000
79
0.013
30
1,164
5.41
325
10
142
166,400
0.9991
0.0142
2.01
0.91
0.3931
129
34
0.0009
100
43
0.0008
9
29
0.32
19
11
761
166,400
0.9954
0.0146
11.1
0.91
0.3931
693
38
0.0046
500
49
0.0042
11
193
1.73
104
12
27,416
166,400
0.8352
0.0111
304.42
0.91
0.3931
24,958
172
0.1648
3,500
254
0.15
83
21,458
62.39
3744
13
14,796
166,400
0.9111
0.0131
194.37
0.91
0.3931
13,469
121
0.0889
3,500
150
0.0809
28
9,969
33.67
2020
14
102
166,400
0.9994
0.0148
1.51
0.91
0.3931
93
34
0.0006
100
31
0.0006
2-
7-
0.23
14
15
88
52,000
0.9983
0.0161
1.42
0.91
0.3931
80
34
0.0017
100
27
0.0015
6-
20-
0.64
39
16
145
52,000
0.9972
0.0182
2.65
0.91
0.3931
132
34
0.0028
100
44
0.0025
10
32
1.06
63
(Q)
Product
TVC
Table 5.35: shows the EPQ Model for the current demand in CTN.
Page | 408
17
399
52,000
0.9923
0.0164
6.53
0.91
0.3931
363
36
0.0077
500
28
0.007
8-
137-
2.91
174
18
356
166,400
0.9979
0.0169
6.02
0.91
0.3931
324
36
0.0021
500
26
0.0019
10-
176-
0.81
49
19
1,327
166,400
0.992
0.0146
19.43
0.91
0.3931
1,208
42
0.008
1,000
47
0.0073
5
208
3.02
181
20
688
52,000
0.9868
0.0176
12.12
0.91
0.3931
626
38
0.0132
500
46
0.012
7
126
5.01
301
21
885
166,400
0.9947
0.0178
15.72
0.91
0.3931
806
40
0.0053
1,000
35
0.0048
5-
194-
2.01
121
22
193
166,400
0.9988
0.0152
2.94
0.91
0.3931
176
34
0.0012
500
15
0.0011
19-
324-
0.44
26
23
871
166,400
0.9948
0.014
12.14
0.91
0.3931
792
38
0.0052
1,000
33
0.0048
5-
208-
1.98
119
24
2,914
166,400
0.9825
0.014
40.79
0.91
0.3931
2,652
52
0.0175
2,000
58
0.0159
6
652
6.63
398
25
81
166,400
0.9995
0.0138
1.12
0.91
0.3931
74
33
0.0005
100
25
0.0004
8-
26-
0.19
11
26
2,380
166,400
0.9857
0.0151
35.82
0.91
0.3931
2,166
49
0.0143
1,000
79
0.013
30
1,166
5.42
325
27
493
166,400
0.997
0.0162
7.97
0.91
0.3931
449
37
0.003
500
34
0.0027
3-
51-
1.12
67
1,780
0.9793 Since <1
Sum
160,061
4,035,200
Since T>Tmin we will choose T*=T
2,174
394
Note: The product numbers are in the same order as they appear in the previous sections. h’ represents the modified holding cost
Page | 409
P/year
∆
h'
λh'
T
Tmin
EPQ (Q*)
λ/P
Q
(Q*)
Tj
TVC(Q) TVC(Q*)
Q*-Q
Tj (Hrs)
Tj (Min)
TVC
Demand (λ)
1
13,154
166,400
0.92
0.013
171.95
0.9103
0.393
11,975
111
0.0791
3,500
136
0.07
24
8,475
29.94
1796
2
1,866
166,400
0.99
0.014
25.98
0.9103
0.393
1,698
45
0.0112
1,000
63
0.01
18
698
4.25
255
3
18,660
166,400
0.89
0.012
226.77
0.9103
0.393
16,987
136
0.1121
3,500
181
0.1
45
13,487
42.47
2548
4
24,809
166,400
0.85
0.011
283.01
0.9103
0.393
22,584
162
0.1491
3,500
233
0.14
71
19,084
56.46
3388
5
24,809
166,400
0.85
0.012
292.51
0.9103
0.393
22,584
166
0.1491
3,500
233
0.14
67
19,084
56.46
3388
6
174
166,400
1
0.014
2.5
0.9103
0.393
158
34
0.001
500
14
0
20-
342-
0.4
24
7
19,922
166,400
0.88
0.012
236.09
0.9103
0.393
18,135
140
0.1197
3,500
191
0.11
51
14,635
45.34
2720
8
252
166,400
1
0.014
3.45
0.9103
0.393
230
35
0.0015
500
19
0
16-
270-
0.57
34
9
2,377
166,400
0.99
0.015
34.58
0.9103
0.393
2,164
49
0.0143
1,000
79
0.01
30
1,164
5.41
325
10
142
166,400
1
0.014
2.01
0.9103
0.393
129
34
0.0009
100
43
0
9
29
0.32
19
11
761
166,400
1
0.015
11.1
0.9103
0.393
693
38
0.0046
500
49
0
11
193
1.73
104
12
27,416
166,400
0.84
0.011
304.42
0.9103
0.393
24,958
172
0.1648
3,500
254
0.15
83
21,458
62.39
3744
13
14,796
166,400
0.91
0.013
194.37
0.9103
0.393
13,469
121
0.0889
3,500
150
0.08
28
9,969
33.67
2020
14
102
166,400
1
0.015
1.51
0.9103
0.393
93
34
0.0006
100
31
0
2-
7-
0.23
14
15
88
52,000
1
0.016
1.42
0.9103
0.393
80
34
0.0017
100
27
0
6-
20-
0.64
39
16
145
52,000
1
0.018
2.65
0.9103
0.393
132
34
0.0028
100
44
0
10
32
1.06
63
17
399
52,000
0.99
0.016
6.53
0.9103
0.393
363
36
0.0077
500
28
0.01
8-
137-
2.91
174
18
356
166,400
1
0.017
6.02
0.9103
0.393
324
36
0.0021
500
26
0
10-
176-
0.81
49
19
1,327
166,400
0.99
0.015
19.43
0.9103
0.393
1,208
42
0.008
1,000
47
0.01
5
208
3.02
181
(Q)
Description
TVC
Table 5.36: shows the EPQ Model for the forecasted demand of year 2009.
Page | 410
20
688
52,000
0.99
0.018
12.12
0.9103
0.393
626
38
0.0132
500
46
0.01
7
126
5.01
301
21
885
166,400
0.99
0.018
15.72
0.9103
0.393
806
40
0.0053
1,000
35
0
5-
194-
2.01
121
22
193
166,400
1
0.015
2.94
0.9103
0.393
176
34
0.0012
500
15
0
19-
324-
0.44
26
23
871
166,400
0.99
0.014
12.14
0.9103
0.393
792
38
0.0052
1,000
33
0
5-
208-
1.98
119
24
2,914
166,400
0.98
0.014
40.79
0.9103
0.393
2,652
52
0.0175
2,000
58
0.02
6
652
6.63
398
25
81
166,400
1
0.014
1.12
0.9103
0.393
74
33
0.0005
100
25
0
8-
26-
0.19
11
26
2,380
166,400
0.99
0.015
35.82
0.9103
0.393
2,166
49
0.0143
1,000
79
0.01
30
1,166
5.42
325
27
493
166,400
1
0.016
7.97
0.9103
0.393
449
37
0.003
500
34
0
3-
51-
1.12
67
1,780
0.9793 Since <1
Sum
160061
4035200
Since T>Tmin we will choose T*=T
2,174
394
Page | 411
Service Level The service level expresses the probability that a certain level of safety stock will not lead to a stock-out. Naturally, when safety stocks are increased, the service level increases as well. Three scenarios of service level percentages were applied to the average demand of the raw materials in order to evaluate the safety stock for each item. If the company applies one of the scenarios, it will consider the safety stock and the total cost for it. Assumptions: The labels, cartons and the spices are locally provided, but the other raw materials are provided from different countries. The local raw materials have an average lead time of one week, while the other materials have an average lead time of three months. The three different service levels tested were 90%, 95%, and 99%. All raw materials follow a normal distribution. Parameters: D: Average demand. Q: Order quantity. L: Lead time. DL: Demand during lead time. µ: Mean. σ: Standard deviation.
Page | 412
Equations: TC(SS) = TC(Q) + h (SS) 𝑧=
𝑥−𝜇 𝜎
The mean and the standard deviation are obtained from the Arena input analyzer.
Page | 413
Table 5.37: Service levels of can plant.
Description
Average Demand
SS Unit
mean
stand.dev
Q
TVC(Q)
h
For 90%
TC (SS) 90%
SS For 95%
TC (SS) 95%
SS For 99%
TC (SS) 99%
Black Eye Beans
88936
K.G
1853
794
10553
75.44
0.02
2869
132.82
3154
138.53
3694
149.32
Broad Beans
768446
K.G
15328
7133
132234
813.74
0.018
24458
1253.99
27026
1300.20
31876
1387.51
Chick Peas 8mm
1168924
K.G
17262
16829
101930
643.12
0.018
38802
1341.56
44860
1450.60
56304
1656.58
Chick Peas 7mm
608219
K.G
12671
5429
27500
243.70
0.026
19620
753.82
21574
804.63
25265
900.60
Chick Peas 10mm
161314
K.G
3361
1440
46309
322.16
0.02
5204
426.24
5722
436.61
6702
456.19
Whole Mushrooms
132455
K.G
3356
7122
18750
291.85
0.045
12471
853.04
15035
968.41
19877
1186.33
109071
K.G
2272
974
18750
288.23
0.045
3518
446.56
3869
462.33
4531
492.12
Green Peas
24859
K.G
7392
5614
61291
261.10
0.013
14577
450.60
16598
476.87
20415
526.49
Mixed Vegetables
37465
K.G
1873
1824
25811
241
0.028
4208
358.75
4865
377.14
6105
411.87
Navy Beans
24859
K.G
3760
9203
53905
116
0.006
15540
209.26
18853
229.14
25111
266.69
White Beans
37465
K.G
518
222
18766
270
0.042
802
303.41
882
306.76
1033
313.10
Peeled Foul
820995
K.G
780.5
334.5
65000
594
0.026
1209
625.44
1329
628.57
1557
634.48
Mushroom Stems and Pieces
Page | 414
Fava Beans
128946
K.G
15709
8098
71153
398
0.017
26075
840.95
28990
890.51
34497
984.13
Red Kidney
24859
K.G
3096
7061
33869
263
0.023
12134
542.51
14676
600.97
19478
711.40
Sweet Corn
208549
K.G
4345
1861.5
33572
289
0.025
6727
457.58
7398
474.33
8663
505.98
Lima Beans
26026
K.G
542.3
232.5
19184
35
0.005
840
39.15
924
39.57
1082
40.36
Carrots
16664
K.G
347.3
149
12000
14
0.003
538
15.57
592
15.73
693
16.04
Sum =
5159.43
9051.23
9600.91
10639.20
After applying the three scenarios for the can plant, it was found that the 90% service level gives the least total cost, which is equal to 728.72 KD/year, according to the safety stock. And the total cost of the current order quantity is equal to 416 KD/year.
Page | 415
Table 5.38: Service levels of beans.
SS Average Description
Demand
Unit
mean
stand.dev
Q
TVC(Q)
h
For
TC (SS)
SS For
TC (SS)
SS For
TC (SS)
90%
90%
95%
95%
99%
99%
Black Eye Beans
88936
K.G
1853
794
10553
75.44
0.02
2869
132.82
3154
138.53
3694
149.32
Broad Beans
768446
K.G
15328
7133
132234
813.74
0.018
24458
1253.99
27026
1300.20
31876
1387.51
Chick Peas 8mm
1168924
K.G
17262
16829
101930
643.12
0.018
38802
1341.56
44860
1450.60
56304
1656.58
Chick Peas 7mm
608219
K.G
12671
5429
27500
243.70
0.026
19620
753.82
21574
804.63
25265
900.60
Chick Peas 10mm
161314
K.G
3361
1440
46309
322.16
0.02
5204
426.24
5722
436.61
6702
456.19
Whole Mushrooms
132455
K.G
3356
7122
18750
291.85
0.045
12471
853.04
15035
968.41
19877
1186.33
Pieces
109071
K.G
2272
974
18750
288.23
0.045
3518
446.56
3869
462.33
4531
492.12
Green Peas
24859
K.G
7392
5614
61291
261.10
0.013
14577
450.60
16598
476.87
20415
526.49
Mixed Vegetables
37465
K.G
1873
1824
25811
241
0.028
4208
358.75
4865
377.14
6105
411.87
Navy Beans
24859
K.G
3760
9203
53905
116
0.006
15540
209.26
18853
229.14
25111
266.69
White Beans
37465
K.G
518
222
18766
270
0.042
802
303.41
882
306.76
1033
313.10
Peeled Foul
820995
K.G
780.5
334.5
65000
594
0.026
1209
625.44
1329
628.57
1557
634.48
Mushroom Stems and
Page | 416
Fava Beans
128946
K.G
15709
8098
71153
398
0.017
26075
840.95
28990
890.51
34497
984.13
Red Kidney
24859
K.G
3096
7061
33869
263
0.023
12134
542.51
14676
600.97
19478
711.40
Sweet Corn
208549
K.G
4345
1861.5
33572
289
0.025
6727
457.58
7398
474.33
8663
505.98
Lima Beans
26026
K.G
542.3
232.5
19184
35
0.005
840
39.15
924
39.57
1082
40.36
Carrots
16664
K.G
347.3
149
12000
14
0.003
538
15.57
592
15.73
693
16.04
Sum =
5159.43
9051.23
9600.91
10639.20
After applying the three scenarios of the service levels for the beans, it was found that the 90% service level once again gives the least total cost, which is equal to 9051.23 KD/year, according to the safety stock. And the total cost of the current order quantity is equal to 5159.43 KD/year.
Page | 417
5.3 Conclusion
Were the EOQ model applied for the last three years, it would have reduced the cost of the company’s total inventory by 3,291 KD/year. Were the EPQ model applied for the last three years, it would have reduced the cost of the company’s total inventory by 12,744 KD/year If the EPQ Model is applied for the year of 2009, the total inventory cost will be reduced by 4,728 KD/year From the three different scenarios, the 90% service level minimized the company’s total inventory costs.
Table 5.38: Total costs for the different service levels.
Service Level
TC(KD/yr)
Scenario 1: 90% 10,079 Scenario 2: 95% 10,664 Scenario 3: 99% 11,768
Page | 418
6. Supply Chain Management
Page | 419
Page | 420
6.1 Introduction
A supply chain consists of all parties involved directly or indirectly in fulfilling a customer request. It is dynamic and involves the constant flow of information, product and funds between different stages. The value a supply chain generates is the difference between what the final product is worth to the customer and the effort the supply chain expends in filling the customer request.
Figure 6.16: Supply chain stages.
The National Canned Food Production and Trading Co.'s supply chain can be classified as a pull system when it comes to meeting demand from its overseas and gulf region customers; it orders its raw materials from its suppliers and manufactures to meet the required demand. For its local customers, based on historical demand from co-ops, wholesalers and small stores, the company keeps an inventory to satisfy it. The company uses two modes of transportation to fulfill its customer's orders; truck loads for transportation by land and ship containers by sea with a capacity of 2100 and 1650 cartons, respectively.
Page | 421
Typical Supply Chain and its Cycles
Manufacturer markets product
Customer places orders
Manufacturer receives orders
Manufacturer order supplies
Supplier fulfill the order
Manufacturer fulfill customer’s order
Manufacturer sends final products to the customer
Figure 6.17: A typical supply chain.
Customer Order Cycle Occurs at the customer/distributor interface and includes all processes directly involved in receiving and filling customer's order.
Customer arrives.
Customer Places Order.
Order is fulfilled.
Order is received.
Page | 422
Manufacturing Cycle Occurs at the distributor/manufacturer interface; related to production scheduling and includes all processes involved in replenishing inventory triggered by:
Customer order.
Replenishment orders.
Forecast of customer demand.
Procurement Cycle Occurs at the manufacturer/supplier interface and includes all processes necessary to ensure that materials are available for all manufacturing to occur according to schedule.
Figure 6.18 - Supply chain cycles.
Cycles are very useful when considering operational decisions because it specifies the roles and responsibilities of each member of the chain. Push/Pull view is very useful when considering the strategic decisions relating to supply chain design.
Page | 423
Warehouses' Locations
There are two warehouses which belong to the National Canned Food Production and Trading Co. One is located at Sabhan and is used for storing final products and only the material/equipment needed for near production. The other warehouse is located in Kabd and is used for storing the packing material until it is needed.
Figure 6.19: Warehouses' location on Kuwait map.
Page | 424
Distribution Network
The National Canned Food Production and Trading Co. distributes its final product, by land, to a local distributor who is then in charge of delivering to the coops, wholesalers and small stores, to six Gulf Countries and ships to two countries in Africa and to Houston, TX. The imported packing and raw materials arrive at Shuwaikh Port. The packing material is then transported to Kabd, and the raw materials to Sabhan. When the packing material is needed, it is then sent to Sabhan. The company manufactures for other gulf countries and the overseas customers based on customer request, but does keep inventory for its local customers.
Figure 6.20: Customers in the Gulf region.
Page | 425
Figure 6.21: Overseas customers.
Page | 426
Figure 6.22: Supply chain network.
Page | 427
Current Average Demand and Costs
Based on historical data, table 6.1 was derived. Note that every truck (sometimes called trailer) has a capacity of 2100 cartons (every carton holds 24 cans) and every container which is used for shipping modes has a capacity of 1650 cartons. Table 6.44: Average demand and transportations costs for all customers.
Avg. Demand
Capacity
Cost
(transporter/month)
of
(KD/transporter)
Total Cost (KD/month)
transporter (carton) Local
28
2100
0
0
KSA (Dammam)
6
2100
200
1200
UAE
5
2100
300
1500
Bahrain
4
2100
290
1160
Qatar
3
2100
300
900
Oman
3
2100
400
1200
Iraq
3
2100
150
450
Tunisia
2
1650
815
1630
USA
3
1650
980
2940
Kenya
3
1650
1300
3900
Totals
122400 cartons/month
14880
Page | 428
Problem Statement
The National Canned Food Production and Trading Co. have to keep the production line running overtime due to the large demand for their products. They are incapable of satisfying demand with their official scheduled working hours. The overtime includes working throughout nights, early mornings and during weekends. The company is at risk of being unable to satisfy the current demand even with overtime production. The company produces 4,000 cartons daily on average (without considering overtime hours), which is equal to 104,000 cartons per month. The total monthly demand on average is equal to 122,400 cartons. This means that the factory produces almost 15% of the demand during overtime. Overtime hours do not come free of charge, however. It costs the company, on average, 1,750 KD every month which is considered as an extra, unnecessary expense for the company and it is a work overload on the workers at the company! The system is thereby risky and expensive.
Page | 429
Solution Approach
After studying the current supply chain of the company, Linear Programming (was used to study the profitability of opening a new factory in 2 potential sites (KSA Dammam and Kuwait), the profitability of using a new mode of transportation, and the profitability of increasing the capacity of the existing factory by replacing the bottleneck machines.
The aim from this study is to raise the company's awareness of the necessity of increasing the company's production capacity and look further into it.
6.2 Analysis and Studies
Assumptions
1. The establishing and fixed costs for the two alternatives are the same. 2. Any regulations regarding establishing a new factory in KSA were overlooked. 3. Costs of transportation from KSA are estimated using the obtained data for transportation from/in Kuwait. 4. Sabhan (Kuwait) will remain to produce for the overseas markets and therefore will not be included in the modeling. 5. The average monthly capacity is 50 truckloads. Since the overseas markets will not be considered, their demand will be deducted from the total monthly capacity. Therefore, the monthly capacity will be 42 cartons.
Page | 430
Table 6.45: Input data.
Demand City (j) Transportation Cost (Cij) per 2100 cartons (KD) (i)
Kuwait - Existing
Monthly Capacity (x2100 cartons)
Kuwait
KSA
UAE
Bahrain
Qatar
Oman
Iraq
(1)
(2)
(3)
(4)
(5)
(6)
(7)
0
200
300
290
300
400
150
42
0
200
300
290
300
400
150
90
200
0
100
90
100
200
350
90
28
6
5
4
3
3
3
Total Demand
(Ki)
(1) Kuwait - Potential (2) KSA - Potential (3) Monthly Demand (Dj) (x2100 cartons)
54
Page | 431
Study 1: Establishing a New Factory
The potential sites for establishing a new factory are Kuwait and KSA - Dammam. Dammam is considered one of the most industrial cities in KSA. It is an easily accessible city. Also, the distributor is located in Dammam, so the cost estimates are valid. The annual maintenance cost of the existing factory in Kuwait is 77,500 KD. The annual equivalent of preventive maintenance costs is 10,800 KD and the annual equivalent of the setup cost was estimated to be 53,070 KD: Setup cost = 300,000 KD A= P (A/P, i =12%, n=10) = 53,070 KD Therefore, the annual equivalent of setup and maintenance costs either in Kuwait or KSA is 63,870 KD. Model Input: Cij : Cost of transporting one truck from i to j. Dj : Demand of j. Ki : Capacity of i. Ai : Annual equivalent of running/establishing factory. Decision Variables: Yij : Whether j is covered by i or not. Si : Whether a factory exists or is established at i or not. Objective Function: Min
1≤ 𝑖 ≤ 3 CijDjYij 1<𝑗 <7
+
1≤ 𝑖 ≤ 3 AiSi 1<𝑗 <7
Page | 432
Constraints: 3 𝑖=1 Yij
= 1
j = 1, 2, … ,7
Ensures that the demand of every market is supplied by one factory. Yij ≤ Si
i = 1, 2, 3 and j = 1, 2, … ,7
Ensures that a factory can only cover a market’s demand if it exists or is established. 7 𝑗 =1 DjYij
≤ KiSi
i = 1, 2, 3
Ensures that the demand supplied by a factory does not exceed its capacity. 3 i=2 Si
= 1
Ensures that only one new factory is opened in either KSA or Kuwait. S1 = 1 Ensures that Kuwait Plant Exists. Yij = {0,1} Whether a market i is supplied by a factory j or not. Si = {0,1}
i = 2,3
Whether a factory is established at KSA or Kuwait min 0Y11 + 1200Y12 + 1500Y13 + 1160Y14 + 900Y15 + 1200Y16 + 450Y17 + 0Y21 + 1200Y22 + 1500Y23 + 1160Y24 + 900Y25 + 1200Y26 + 450Y27 + 5600Y31 + 0Y32 + 500Y33 + 360Y34 + 300Y35 + 600Y36 + 1050Y37 + 6458S1 + 5323S2 + 5323S3 st Y11 + Y21 + Y31 = 1 Y12 + Y22 + Y32 = 1 Y13 + Y23 + Y33 = 1 Y14 + Y24 + Y34 = 1 Y15 + Y25 + Y35 = 1
Page | 433
Y16 + Y26 + Y36 = 1 Y17 + Y27 + Y37 = 1 Y21 - S2 <= 0 Y22 - S2 <= 0 Y23 - S2 <= 0 Y24 - S2 <= 0 Y25 - S2 <= 0 Y26 - S2 <= 0 Y27 - S2 <= 0 Y31 - S3 <= 0 Y32 - S3 <= 0 Y33 - S3 <= 0 Y34 - S3 <= 0 Y35 - S3 <= 0 Y36 - S3 <= 0 Y37 - S3 <= 0 S1= 1 S2 + S3 = 1 28Y11 + 6Y12 + 5Y13 + 4Y14 + 3Y15 + 3Y16 + 3Y17 - 42S1<= 0 28Y21 + 6Y22 + 5Y23 + 4Y24 + 3Y25 + 3Y26 + 3Y27 - 90S2 <= 0 28Y31 + 6Y32 + 5Y33 + 4Y34 + 3Y35 + 3Y36 + 3Y37 - 90S3 <= 0 end int Y11 int Y12 int Y13
Page | 434
int Y14 int Y15 int Y16 int Y17 int Y21 int Y22 int Y23 int Y24 int Y25 int Y26 int Y27 int Y31 int Y32 int Y33 int Y34 int Y35 int Y36 int Y37 int S2 int S3
Page | 435
Output Results showed that a new factory should be established in KSA and the distribution plan is as follows. Table 6.46: Model 1 output.
DjYij
Kuwait
KSA
UAE
Bahrain
Qatar
Oman
Iraq
Total Truck loads
Kuwait
28
0
0
0
0
0
3
31
KSA
0
6
5
4
3
3
0
21
Total Cost = 13991 KD/month
S2 = 0 S3 = 1 *For more details refer to Appendix O for the Lindo output.
Page | 436
Study 2: Using New Trucks
KGL sends trucks with a capacity of 67.7 m3, to two of the existing customers. Thus, the capacity of the new truck is 4130 cartons. We will study if using these trucks as a mode of transportation from Kuwait to KSA - Dammam and UAE will help reduce transportation costs in comparison to establishing a new factory. Table 6.47: Price quotation from KGL.
KSA - Dammam
UAE
300
450
3
3
Cost from Kuwait (KD/truck) Average Demand (truck/month)
Model Input: Cij : Cost of transporting one truck from i to j. Dj : Demand of j. Ki : Capacity of i. Decision Variables: Yij : Whether j is covered by i or not. Si : Whether a factory exists or is established at i or not. Tij : Whether the new trucks are used to transport from i to j. Objective Function: Min
1≤ 𝑖 ≤ 3 CijDjYij 1<𝑗 <7
+
3 𝑖=1 AiSi
+
1≤ 𝑖 ≤ 3 CijDjTij 1<𝑗 <7
Page | 437
Constraints: 3 𝑖=1 Yij
+ Tij = 1
j = 2, 3
Ensures that the demand of every market is supplied by one factory using one mode of transportation. 3 𝑖=1 Yij
= 1
j = 1, 4, 5, 6, 7
Ensures that the demand of every market is supplied by one factory. Yij ≤ Si
i = 1, 2, 3 and j = 1, 2, … , 7
Ensures that a factory can only cover a market's demand if it exists or is established. 7 𝑗 =1 DjYij
+ DjTij ≤ KiSi
i = 1, 2, 3
Ensures that the demand supplied by a factory by one mode of transportation does not exceed its capacity. 3 i=2 Si
= 1
Ensures that only one new factory is opened at either KSA or Kuwait. S1 = 1 Ensures that Kuwait Plant Exists. Yij = {0,1} Whether a market i is supplied by a factory j or not. Si = {0,1}
i = 2,3
Whether a factory is established at KSA or Kuwait
Page | 438
min 0Y11 + 1200Y12 + 900T12 + 1500Y13 + 1125T13 + 1160Y14 + 900Y15 + 1200Y16 + 450Y17 + 0Y21 + 1200Y22 + 1500Y23 + 1160Y24 + 900Y25 + 1200Y26 + 450Y27 + 5600Y31 + 0Y32 + 500Y33 + 360Y34 + 300Y35 + 600Y36 + 1050Y37 + 6458S1 + 5323S2 + 5323S3 st Y11 + Y21 + Y31 = 1 Y12 + Y22 + Y32 + T12 = 1 Y13 + Y23 + Y33 + T13 = 1 Y14 + Y24 + Y34 = 1 Y15 + Y25 + Y35 = 1 Y16 + Y26 + Y36 = 1 Y17 + Y27 + Y37 = 1 Y21 - S2 <= 0 Y22 - S2 <= 0 Y23 - S2 <= 0 Y24 - S2 <= 0 Y25 - S2 <= 0 Y26 - S2 <= 0 Y27 - S2 <= 0 Y31 - S3 <= 0 Y32 - S3 <= 0 Y33 - S3 <= 0 Y34 - S3 <= 0 Y35 - S3 <= 0 Y36 - S3 <= 0 Y37 - S3 <= 0
Page | 439
S1= 1 S2 + S3 = 1 28Y11 + 6Y12 + 3t12+ 3t13 + 5Y13 + 4Y14 + 3Y15 + 3Y16 + 3Y17 - 42S1 <= 0 28Y21 + 6Y22 + 5Y23 + 4Y24 + 3Y25 + 3Y26 + 3Y27 - 90S2 <= 0 28Y31 + 6Y32 + 5Y33 + 4Y34 + 3Y35 + 3Y36 + 3Y37 - 90S3 <= 0 end int Y11 int Y12 int Y13 int Y14 int Y15 int Y16 int Y17 int Y21 int Y22 int Y23 int Y24 int Y25 int Y26 int Y27 int Y31 int Y32 int Y33 int Y34 int Y35
Page | 440
int Y36 int Y37 int S2 int S3 int T12 int T13
Output Results showed that the best option is establishing a new factory in KSA again. Table 6.48: Model 2 output.
DjYij
Kuwait
KSA
UAE
Bahrain
Qatar
Oman
Iraq
Total Truck loads
Kuwait
28
0
0
0
0
0
3
31
KSA
0
6
5
4
3
3
0
21
Total Cost = 13991 KD/month S2 = 0 S3 = 1 T12 = 0 T13 = 0 *For more details refer to Appendix O for the Lindo output.
Page | 441
Justifications for Study 1 and Study 2
Current Situation N.B. The following data was used to estimate the costs and was obtained from the Cost Analysis Group. Table 6.49: Annual costs.
Cost (KD/year) Overtime
21,000
Maintenance
77,500
Operation Costs
178,560
Transportation
145,812
These are the costs considered when opening the new factory. A cash flow diagram was developed to calculate the present worth of the current existing factory in Kuwait. The interest rate used was 12% and calculated over a period of 10 years.
PW = 2,389,322 KD
Page | 442
Current (Kuwait) Factory in New Situation Maintenance costs remain the same because the machines are untouched. The transportation costs include only the costs involved in the new distribution plan. The operation costs are equal to 65% of the current operation costs because the current factory in the new situation will be responsible for producing only 65% of its current production.
PW = 1,578,209 KD
Page | 443
New Factory Since it is a new factory, no corrective maintenance should be applied in normal conditions. However, the preventive maintenance will be carried on the same schedule as the current factory which will result in constant costs. The new factory will be shipping to KSA, Bahrain, UAE, Qatar and Oman. These locations demand 35% of the current production and operation costs are calculated based on that.
PW = 768,715 KD Therefore, the Total Present Worth was calculated for the company by summing the PW for the current factory in the new situation and that of the new factory. PW = 1,578,209 + 768,715 = 2,346,924 KD Total Cost Savings = ((2,389,322 - 2,346,924)/ 2,389,322) x 100 = 1.77 %
Page | 444
Study 3: Increasing Capacity of Existing Factory The capacity of the existing factory in Kuwait could be increased if the bottle neck machines were replaced. In the following model this option was included in addition to the previous two alternatives and also relaxing the constraint so that more than one alternative could be feasible. The new average production speed would equal about 290 - 300 cans/min after replacing the bottleneck machines. Therefore, the average monthly capacity is 90 truckloads. Using average cost values obtained from Elmar, an industry leader in the manufacturing and design of a wide variety of machines (http://www.nov.com/elmar/), the annual equivalent of expanding the capacity cost was estimated to be KD 11,522. Model Input: Cij : Cost of transporting one truck from i to j. Dj : Demand of j. Ki : Capacity of i. Ui : Increase in capacity of i. Decision Variables: Yij : Whether j is covered by i or not. Si : Whether a factory exists or is established at i or not. Tij : Whether the new trucks are used to transport from I to j. Qi : Whether the capacity of factory i is increased or not. Objective Function: Min
1≤ 𝑖 ≤ 3 CijDjYij 1<𝑗 <7
+
3 𝑖=1 AiSi
+
1≤ 𝑖 ≤ 3 CijDjTij 1<𝑗 <7
+
1 i=1 AiQi
Page | 445
Constraints: 3 𝑖=1 Yij
+ Tij = 1
j = 2, 3
Ensures that the demand of every market is supplied by one factory using one mode of transportation. 3 𝑖=1 Yij
= 1
j = 1, 4, 5, 6, 7
Ensures that the demand of every market is supplied by one factory. Yij ≤ Si
i = 1, 2, 3 and j = 1, 2, … , 7
Ensures that a factory can only cover a market's demand if it exists or is established. 7 𝑗 =1 DjYij
+ DjTij ≤ KiSi + QiUi
i = 1, 2, 3
Ensures that the demand supplied by a factory by one mode of transportation does not exceed its capacity. 3 i=2 Si
= 1
Ensures that only one new factory is opened at either KSA or Kuwait. S1 = 1 Ensures that Kuwait Plant Exists. Yij = {0,1} Whether a market i is supplied by a factory j or not. Si = {0,1}
i = 2,3
Whether a factory is established at KSA or Kuwait
Page | 446
min 0Y11 + 1200Y12 + 900T12 + 1500Y13 + 1125T13 + 1160Y14 + 900Y15 + 1200Y16 + 450y17 + 0Y21 + 1200Y22 + 1500Y23 + 1160Y24 + 900Y25 + 1200Y26 + 450Y27 + 5600Y31 + 0Y32 + 500Y33 + 360Y34 + 300Y35 + 600Y36 + 1050Y37 + 6458S1 + 5323S2 + 5323S3 + 960Q1 st Y11 + Y21 + Y31 = 1 Y12 + Y22 + Y32 + T12 = 1 Y13 + Y23 + Y33 + T13 = 1 Y14 + Y24 + Y34 = 1 Y15 + Y25 + Y35 = 1 Y16 + Y26 + Y36 = 1 Y17 + Y27 + Y37 = 1 Y21 - S2 <= 0 Y22 - S2 <= 0 Y23 - S2 <= 0 Y24 - S2 <= 0 Y25 - S2 <= 0 Y26 - S2 <= 0 Y27 - S2 <= 0 Y31 - S3 <= 0 Y32 - S3 <= 0 Y33 - S3 <= 0 Y34 - S3 <= 0 Y35 - S3 <= 0 Y36 - S3 <= 0 Y37 - S3 <= 0
Page | 447
S1= 1 28Y11 + 6Y12 + 3T12+ 3T13 + 5Y13 + 4Y14 + 3Y15 + 3Y16 + 3Y17 – 42S1 – 48Q1 <= 0 28Y21 + 6Y22 + 5Y23 + 4Y24 + 3Y25 + 3Y26 + 3Y27 – 90S2 <= 0 28Y31 + 6Y32 + 5Y33 + 4Y34 + 3Y35 + 3Y36 + 3Y37 – 90S3 <= 0 end int Y11 int Y12 int Y13 int Y14 int Y15 int Y16 int Y17 int Y21 int Y22 int Y23 int Y24 int Y25 int Y26 int Y27 int Y31 int Y32 int Y33 int Y34 int Y35 int Y36
Page | 448
int Y37 int S2 int S3 int T12 int T13 int Q1
Output Results showed that increasing the capacity of the existing plant in Kuwait is the best option alongside using the new modes of transport. Table 6.50: Model 3 output.
DjYij
Kuwait
KSA
UAE
Bahrain
Qatar
Oman
Iraq
Total Truck loads
Kuwait (old truck)
28
0
0
4
3
3
3
41
Kuwait
0
3
3
0
0
0
0
6
(new truck) Total Cost = 13153 KD/month S2 = 0 S3 = 0 Q1 = 1 T12 = 1 T13 = 1 *For more details refer to Appendix O for the Lindo output. Page | 449
Study 4: Demand Increase
In the likely case of an increase in demand, decisions may change. Using the demand forecasted for the next 5 years by the inventory control group, an average monthly demand was calculated and the following results were obtained. Using the same model as study 3, results were obtained in order to develop a distribution plan in order to meet the forecasted demand.
Page | 450
Table 6.51: Forecasted average demand.
Demand City (j) Transportation Cost (Cij) per 2100 cartons (KD) (i)
Kuwait - Existing
Monthly Capacity (x2100 cartons)
Kuwait
KSA
UAE
Bahrain
Qatar
Oman
Iraq
(1)
(2)
(3)
(4)
(5)
(6)
(7)
0
200
300
290
300
400
150
42
0
200
300
290
300
400
150
90
200
0
100
90
100
200
350
90
33
8
7
5
4
4
7
Total Demand
(Ki)
(1) Kuwait - Potential (2) KSA - Potential (3) FORECASTEDMonthly Demand (Di) (x2100 cartons)
68
Page | 451
min 0Y11 + 1600Y12 + 1500T12 + 2100Y13 + 2250T13 + 1450Y14 + 1200Y15 + 1600Y16 + 1050Y17 + 0Y21 + 1600Y22 + 2100Y23 + 1450Y24 + 1200Y25 + 1600Y26 + 1050Y27 + 6600Y31 + 0Y32 + 700Y33 + 450Y34 + 400Y35 + 800Y36 + 2450Y37 + 6458S1 +
5323S2
+ 5323S3 + 960Q1 st Y11 + Y21 + Y31 = 1 Y12 + Y22 + Y32 + T12 = 1 Y13 + Y23 + Y33 + T13 = 1 Y14 + Y24 + Y34 = 1 Y15 + Y25 + Y35 = 1 Y16 + Y26 + Y36 = 1 Y17 + Y27 + Y37 = 1 Y21 - S2 <= 0 Y22 - S2 <= 0 Y23 - S2 <= 0 Y24 - S2 <= 0 Y25 - S2 <= 0 Y26 - S2 <= 0 Y27 - S2 <= 0 Y31 - S3 <= 0 Y32 - S3 <= 0 Y33 - S3 <= 0 Y34 - S3 <= 0 Y35 - S3 <= 0 Y36 - S3 <= 0
Page | 452
Y37 - S3 <= 0 S1= 1 33Y11 + 8Y12 + 5T12 + 5T13 + 7Y13 + 5Y14 + 4Y15 + 4Y16 + 7Y17 – 42S1 – 48Q1 <= 0 33Y21 + 8Y22 + 7Y23 + 5Y24 + 4Y25 + 4Y26 + 7Y27 – 90S2 <= 0 33Y31 + 8Y32 + 7Y33 + 5Y34 + 4Y35 + 4Y36 + 7Y37 – 90S3 <= 0 end int Y11 int Y12 int Y13 int Y14 int Y15 int Y16 int Y17 int Y21 int Y22 int Y23 int Y24 int Y25 int Y26 int Y27 int Y31 int Y32 int Y33 int Y34
Page | 453
int Y35 int Y36 int Y37 int S2 int S3 int T12 int T13 int Q1
Output Results showed that establishing a factory in KSA would be the most feasible solution in the case of an increase in demand. Table 6.52: Model 4 output.
DjYij
Kuwait
KSA
UAE
Bahrain
Qatar
Oman
Iraq
Total Truck loads
Kuwait
33
0
0
0
0
0
7
60
0
8
7
5
4
4
0
5
Existing KSA Potential Total Cost = 15181.00 KD/month S2 = 0 S3 = 1 Q1 = 0
Page | 454
T12 = 0 T13 = 0 *For more details refer to Appendix O for the Lindo output.
6.3 Conclusion
Throughout this analysis, alternatives were studied in order to overcome the problem regarding the production capacity of the factory. The alternatives studied were whether to increase the capacity of the current factory, establish a new factory, and also, to reduce shipping costs, new modes of transportation were introduced where the unit shipping cost is less than for the existing modes. With the current average demand, it is suggested to increase the capacity of the existing Kuwait factory and use the new modes of transportation introduced. The initial associated transportation costs were 14880 KD/month; the cost resulting from the suggested distribution plan is 13153 KD/month, resulting in savings of 11.6%. Since the National Canned Food Production and Trading CO. is becoming more and more known throughout the region and internationally, there is an expected increase in demand, which the company may not be able to satisfy with their current production capacity. It is safe to assume so because of the fact that they are already working overtime to satisfy the current demand. Therefore, it would seem necessary for the company to increase their production capacity in order to be able to satisfy the future forecasted demand.
Page | 455
Page | 456
7. Safety & Human Factors
Page | 457
Page | 458
7.1 Introduction
The working conditions inside the factory were examined and it was determined whether they are safe. It was attempted to remove all hazards from the workplace and to try to minimize the chances of workers sustaining significant injuries. By applying multiple human factors tools as RULA and the NIOSH lifting equation, the aim was to eradicate any unhealthy postures during work or activities that cause too much fatigue to the workers. Also, the company was educated on the important role that safety and human factors engineers can play in ensuring the safety of their workers and avoiding any expensive accidents from occurring.
Problem Description By observing the factory, it was noticed that there is no significant attention paid to the safety and human factors aspects of the work being done. There were wet floors, crammed machines, and no signs instructing workers to wear protective equipment. Furthermore, many of the work activities were not ergonomically sound.
Page | 459
Objectives It was immediately noticed that there are major opportunities for improvement in the environment of the factory. The workers’ body positions as well as other areas that safety and human factors can cover were studied with the aim to:
Improve operational performance.
Enhance effectiveness and efficiency.
Ensure the work environment can be used conveniently.
Make workers comfortable in their surrounding environment.
Reduce human errors.
Increase productivity.
Improve safety.
Reduce fatigue and stress.
Get workers’ acceptance.
Increase job satisfaction.
Improve the quality of life.
Note that, achieving the objectives above leads to a reduction in the number of accidents which will go towards eliminating the direct and indirect costs of an accident.
Solution Approach Safety and human factors tools such as RULA and NIOSH were used to evaluate
all
work
activities.
When
activities
were
found
to
be
unsafe,
recommendations to modify them were suggested.
Page | 460
7.2 Safety and Human Factors
Even though technology is advancing at an exponential rate, there are still work activities with manual handling of material, supplies, and tools often requiring workers to expend moderate to high level of physical energy to perform them. Engineers must make sure that products, workplaces, environments, buildings, vehicles and systems are safe since they affect the way a worker may act, and may eventually cause an accident. The Domino Theory states that an accident sequence is like a series of five dominos standing on end, one can knock the others over. The five dominos in reverse sequence are injuries caused by an action which, in turn, is caused by an unsafe act or condition, caused by undesirable traits (nervousness, violent temper, lack of knowledge,…etc.), that are developed because of unsafe environment.
Undesirable Traits
INJURY
Unsafe Environment
Accident
Unsafe Act
Figure 7.1: Dominos theory.
At the same time, engineers work in an economic system that requires businesses and enterprises to be competitive. Safety and human factors make ergonomic sense as well as moral and legal sense.
Page | 461
So to achieve safety through engineering, engineers need to understand:
The duties and responsibilities for which they are accountable.
The hazards and engineering controls for them.
Human behavior, capabilities and limitations.
How to identify hazards and present the need for controls to the managers.
Engineers work mainly on the preventive side of safety, where they must identify the hazards during design and eliminate or reduce them. They also prevent unsafe behavior by designing the product, workplace and environment in a way that unsafe behaviors are not likely to occur. Industrial engineers work mainly on fitting the job to people and designing work methods to improve the fit between people and their equipment, environment, system, workplace or information, to improve workers performance and safety. Safety engineering is the application of scientific and engineering principals and methods to the elimination and control of hazards. Also it is the state of being free from harm, danger, injury or damage. Human factors is a term that covers:
The science of understanding the properties of human capability (Human Factors Science).
The application of this understanding to the design and development of systems and services (Human Factors Engineering).
The art of ensuring successful application of Human Factors Engineering to a program.
Page | 462
7.3 Hazard Categories
A hazard is a situation which poses a level of threat to life, health, property or environment. Most hazards are dormant or potential, with only a theoretical risk of harm. However, once a hazard becomes 'active', it can create an emergency situation.
1. Biological Hazards include bacteria, viruses, insects, plants, birds, animals, and humans. These sources can cause a variety of health effects ranging from skin irritation and allergies to infections (e.g., tuberculosis, AIDS), cancer and so on.
2. Chemical hazards are present when a worker is exposed to any chemical preparation in the workplace in any form (solid, liquid or gas). Some are safer than others, but to some workers who are more sensitive to chemicals, even common solutions can cause illness, skin irritation or breathing problems. Beware of:
Liquids, such as cleaning products, paints, acids, solvents especially chemicals in an unlabelled container.
Vapors and fumes, for instance those that come from welding or exposure to solvents.
Gases like acetylene, propane, carbon monoxide and helium.
Flammable materials like gasoline, solvents and explosive chemicals.
Page | 463
3. Ergonomic Hazards occur when the type of work, body position and working conditions put strain on your body. They are the hardest to spot since the strain on the body and the harm they pose are immediately noticeable. Shortterm exposure may result in "sore muscles" the next day or in the days following exposure, but long term exposure can result in serious long-term injuries. Ergonomic hazards include:
Poor lighting.
Improperly adjusted workstations and chairs.
Frequent lifting.
Poor posture.
Awkward movements, especially if they are repetitive.
Repeating the same movements over and over.
Having to use too much force, especially if repeated frequently.
4. Physical Hazards are the most common and will be present in most workplaces at one time or another. They include unsafe conditions that can cause injury, illness and death. They are typically easiest to spot but often overlooked because of familiarity, lack of knowledge, resistance to spending time or money to make necessary improvements or simply delays in making changes to remove the hazards. None of these are acceptable reasons for workers to be exposed to physical hazards. Examples of physical hazards include:
Electrical hazards such as frayed cords, missing ground pins, improper wiring.
Unguarded machinery and moving machinery parts, guards removed or moving parts that a worker can accidentally touch.
Constant loud noise.
High exposure to sunlight/ultraviolet rays, heat or cold.
Working from heights, including ladders, scaffolds, roofs, or any raised work area.
Working with mobile equipment such as forklifts since they require significant additional training and experience. Page | 464
7.4 Worker interaction with machine and material
The areas where the workers interact with the machine, raw materials, or final product through the production process are discussed below. Can Production Line: 1. Slitting: In the slitting process, a worker standing that feeds the tin sheets into the slitting machine. 2. Blanks are manually fed by the same worker to the welder. 3. Welding: In this step there is a welding test applied by a single worker. 4. Seaming: A worker manually feeds the seaming machine with the lids. Filling Line: 1. Soaking: Tanks are manually filled by a worker. 2. Inspection belt: The solid material is sorted manually by 4-6 workers to remove any dark or broken pieces. 3. Crate loading: 700 cans are put on a crate manually and are taken to the sterilizing stage by a trolley. 4. Sterilizing: The crates are pushed into the sterilizing machine manually. 5. Crate unloading: The cans are unloaded from the crate to the labeler manually. 6. Label inspection: Checking the quality of the labels is done manually by a specialized worker. 7. Every 20 cartons are put in a pallet by two workers and one fork lift.
Page | 465
7.5 Data Collection and Findings
To collect information accurately and easily identify the hazards around the factory, steps were taken to summarize the findings to make it easier to improve the system and reduce the hazards. Safety Checklists: A checklist is used as an aid to memory. It helps to ensure consistency and completeness in carrying out a task. A more advanced checklist would be a schedule, which lays out tasks to be done according to time of day or other factors. Safety and Human factors Survey Table: A survey table is a technique used to gather the findings and summarize them into categories.
Safety and Human Factors Checklists1: Applying a number of safety and human factors checklists covered a large part of the workplace which led to general conclusions regarding to safety hazards: a. Work Environment: The factory has a ventilation system but does not have an air conditioning system which causes
an
increase
in
temperature
and
humidity in summer, adversely affecting worker performance. The noise level in the factory was very high. Figure 7.2: Ventilation system.
1
For more details, Check Appendix (P)
Page | 466
The lighting of the factory was deemed acceptable is the roof of the factory allows the sun light through (which provides natural lighting in addition to the electrical lighting system in the factory). However, some areas need some enhancement in the lightning system because the illumination is not enough
Figure 7.3: Lighting system.
or there are glare issues. The poor machine layout and the unorganized raw material and final products storage area cause some workers to face some difficulties in moving from one machine to another. Since the factory deals with the production of caned food which involves the use of a massive amount of fluids in the process line, the ground is always wet, causing slipping accidents. b. Fire Protection: Figure 7.4: Wet ground.
The factory has an automatic fire fighting and detection system that is sensitive to smoke and fire. There are 4 fire hose reels distributed around the factory plant and 8 fire extinguishers. c. Emergency Exits:
Figure 7.5: Fire extinguishers.
The factory has 7 emergency exits distributed in several places around the factory plant. Some emergency exits are difficult to reach or access because of the presence of obstacles in the way. Stockpiles of raw material also hinder the passage of workers.
Figure 7.6: Blocked emergency exit.
Page | 467
d. Safety Signs: There are no information and warning signs that remind the workers of the importance of wearing protective gear (for example boots, gloves, eye protectors, coats, helmets and earmuffs).
Uncomfortable Body Postures1:
Figure 7.7: Instruction boards.
The design of the machines and the working tasks forced the workers to adopt uncomfortable postures that require further study by applying Human Factors methods.
Safety and Human Factors Survey Forming a safety and human factors survey table that contains all the findings that were recognized when studying the factory made it easier to identify the type of hazard and the way to remove or reduce it. The survey table contains the number of findings, type, date, location (Fig.#), description, and data available. The information gathered will be then used in: Quick-Win Improvement Table contains the findings that can be easily solved and the number of findings. The findings that can be solved by the same recommendation are grouped together to faciliate their solution. Long Term Improvement Table contains findings that need further studying by applying human factors and safety tools where the findings can not be solved easily and need further investigation.
1
For pictures, check Appendix (Q)
Page | 468
Location Layout
Figure 7.8: Location of hazard layout.
Page | 469
Safety and Human Factors Survey Table 1
Table 7.53: Safety and human factors survey .
Finding
Hazard Type
Date
Location
Description
Data
1
Chemical
ET
Out Doors
H2S Gas.
Video
2
Physical
ET
EW
Wet floor everywhere, except storage areas.
V+P
3
Physical
ET
EW
Very high noise level.
Video
4
Safety
ET
EW
No safety signs.
Picture
5
Ergonomic
ET
L2
Workers are sorting beans to remove any dark or broken pieces.
Video
6
Ergonomic
ET
L2
Workers standing/sitting for long periods of time.
Picture
7
Ergonomic
ET
L2
Uncomfortable chairs.
Picture
8
Ergonomic
ET
L3
Operators standing all the time.
Video
9
Ergonomic
ET
L3
Hard to move and a need to bend under machines to pass.
V+P
10
Ergonomic
ET
L4
Empty crates are pulled from the empty crate area to the crate loading machine.
Video
11
Ergonomic
ET
L4
700 cans are put on a crate.
Video
12
Ergonomic
ET
L4
Pushing full crate to sterilizing machine.
Video
13
Ergonomic
ET
L5
Push full basket into retort.
Video
1
ET: Every time, EW: Everywhere, Data: Represents the available data about the finding, Pictures: for more details, see Appendix (Q), Video: For more details, Check attached CD. V+P: Video and Pictures are available
Page | 470
Table 7.54: Cont. safety and human factors survey.
Finding
Hazard Type
Date
Location
Description
Data
14
Ergonomic
ET
L5
Pull full basket from retort.
-
15
Chemical
ET
L5
Facing hot steam from sterilizing machine
Video
16
Ergonomic
ET
L5
Push full basket to unloading machine.
Video
17
Ergonomic
ET
L6
Pull & push to unload from basket to labeling machine.
Video
18
Ergonomic
ET
L6
Pull & Push empty basket back to empty crate area.
Video
19
Ergonomic
ET
L7
Labels are manually inspected by a single worker.
V+P
20
Ergonomic
ET
L8
Stacking product on pallets.
Video
21
Ergonomic
ET
L8
Pulling empty pallet.
V+P
22
Physical
ET
L9
Very high noise level next to the welding machine.
Video
23
Ergonomic
ET
L9
Loading welding machine with 5 to 10 kg group of blanks.
V+P
24
Ergonomic
ET
L9
Feeding slitting machine with tin sheets.
Video
25
Ergonomic
8\11
L9
Applying welding test on welded blanks.
Video
26
Ergonomic
8\11
L9
Using old and heavy tools to apply test.
Video
27
Ergonomic
8\11
L9
Operators setting up the seaming machine.
Video
28
Physical
17\11
EW
High temperature & humidity levels.
-
29
Physical
17\11
EW
Glare on instruction boards.
Picture
Page | 471
Table 7.55: Cont. safety and human factors survey.
Finding
Hazard Type
Date
Location
Description
Data
30
Safety
17\11
L2
Emergency exit was blocked.
video
31
Ergonomic
17\11
L2
Filling machine from heavy oil drums.
V+P
32
Physical
17\11
L5
Unstable pressure gauge.
Video
33
Ergonomic
17\11
L5
Operator setting up sterilizing machine.
Picture
34
Ergonomic
17\11
L7
Operator setting up labeling machine.
V+P
35
Safety
26\11
L1
Emergency exit was blocked.
Picture
36
Safety
26\11
L1
Lifting worker on a forklift
Video
37
Ergonomic
26\11
L3
Manual can filling.
Video
38
Safety
26\11
L3
Emergency exit was blocked.
V+P
39
Safety
26\11
L9
Emergency exit was blocked.
Picture
40
Safety
26\11
L 10
Emergency exit not obvious and hard to reach.
Video
41
Ergonomic
26\11
L 10
Control buttons are not classified.
Picture
42
Safety
26\11
L 11
Emergency exit was blocked and located next to the main door.
Picture
43
Safety
26\11
L 11
Lifting worker on a forklift.
Video
44
Ergonomic
28\11
L1
Workers lifting 50 kg beans bags to fill tanks.
Video
45
Safety
5\12
L8
Forklift bumps into worker.
Video
Page | 472
7.6 Quick-win Improvements Table 7.56: Quick win Improvement.
No.
Finding #
Hazard Description
1
2
Slippery floor
2
3,22
High noise level
3
4
No safety signs
4
5,11,19,20,24,37
Repetitive motion
5
7
Uncomfortable chairs.
6
8
Standing all the time.
7
15
Hot steam.
8
26
Old, heavy, and unergonomically designed tools.
9
28
High temperature and humidity level.
10
29
Glare on instruction board.
11
30,35,38,39,40,42
Blocked emergency exits.
12
32
Unstable pressure gauge.
13
36,43
Lifting workers on a forklift.
14
41
Control buttons without instructions.
Recommendations
Try as much as possible to minimize the amount of water while cleaning the factory. Wear boots.
Wear ear muffs.
Add instruction board that contains safety signs.
Educate workers on the importance of changing their body posture every once in a while. Change worker every so often.
Use chairs that are ergonomically designed.
Provide workers with chairs so that they can rest every once in a while.
Replace old tools with light, ergonomically designed tools.
Add fans to the factory to reduce the temperature and humidity levels.
Change the material of the board to a type that does not reflect light. Change the position of the board to reduce the glare effect.
Educate workers to the importance of clearing the area around the emergency exit.
Wear protective masks.
Replace with new one.
Educate workers to the risks of their action.
Add instructions to show their use.
Page | 473
Figure 7.9: Safety instruction board
7.7 Long-term Improvement Table 7.57: Long term improvement.
No.
Finding #
Tool Used
Hazard Description
Recommendations
1
1
-
H2S Gas.
The government should provide a sewage system.
2
9
-
Not easy to move from one machine to another.
Rearrange machine layout.
3
5,6,11,19,20,23,2 4,25,27,31,33,34, 44
RULA
Uncomfortable\awkward body posture with repetitive motion.
1
4
10,12,17,18,21
SNOOK tables
Push\pull heavy items (Create \Pallet).
*
5
20,23,44
NIOSH
Repetitive lifting with body twisting.
*
6
5,11,13,19,20, 23
RRM
Long working hours.
*
*
* Note that recommendations will be explained separately for each case in the next section.
Page | 474
Methodologies Human factors tools were applied on the findings introduced in the long term improvement table, to rank the findings and determine whether to change it.
RULA RULA is a quick survey method for use in ergonomic investigations of workplaces where muscular skeletal disorders are reported. It is a screening tool that assesses biomechanical and postural loading on the whole body. RULA scores indicate the level of intervention required to reduce MSD (Muscular skeletal disorders) risks. Furthermore, it compliments other ergonomic methods. RULA can be applied manually, through a program from the following site “http:\\www.rula.co.uk\survey.html”, or through Job Hazard Pro1. Most of the postures have been assessed manually except for a posture that has two different scores, one for the right hand and one for the left. The score was found using the program as an example. Print screen of the final outcome is available below. For the grand score “C” of the posture assessment: A score of one or two shows an acceptable posture. A score of three or four indicates further investigation is needed and changes may be required. A score of five or six indicates investigation and changes are required soon. A score of seven or more indicates investigation and changes are required immediately.
1
It includes five major risk assessment tools, which are recognized and recommended by OSHA.
Page | 475
By using RULA software the final score, action, and action level for each location in the factory were obtained.1 Filling Line: Case description: In this case female workers repetitively separate the beans from dark or broken ones.
Final RULA score: 4
Action: Investigate further. Figure 7.10
Recommendation: Use ergonomically designed chairs with back rest, and lower the chair height so that the worker does not need to bend.
Case description: A male worker is filling a machine with oil. The process takes more than one minute in the same body posture. Final RULA score: 7 Action: Investigate and change immediately. Figure 7.11
Recommendation: Place the oil tank in a high place and use an alternative method for filling.
1
For more details, see Appendix (R)
Page | 476
Case Description: Male worker is repetitively loading cans into a crate, with 700 cans fitting into one crate.
Final RULA score: 7
Action: Investigate and change immediately.
Recommendation: Use an automated loading machine where the worker only has to operate it and not apply too much muscular force to load the cans into the crate. Figure 7.12
Case Description: Operator is setting up the labeling machine
Final RULA score: 3
Action: Investigate further.
Recommendation: Educate the worker on the importance of changing his body posture while setting up the machine; for example, bending his knees rather than his back. Figure 7.13
Page | 477
Case Description: Male worker inspects lables.
Final RULA score: 4
Action: Investigate further.
Recommendation: Educate the worker on the importance of changing his body posture every once in a while. Train different workers to do the same job to break the repetitive sequence. Figure 7.14
Case Description: Male worker is stacking the final product which in a box that contains 24 cans, weighing 400g each.
Final RULA score: 7
Action: Investigate and change immediately. Figure 7.11
Recommendation: Introduce an automated machine that stacks the boxes instead of the worker. The worker would only
Figure 7.15
have to operate it rather than repetitively lift the boxes.
Page | 478
Can Line: Case Description: Male worker is applying welding test on a welded can to check the quality of the weld.
Final RULA score: 7
Action: Investigate and change immediately. Recommendation:
Figure 7.16
Change the tool into an ergonomically designed one to make testing easier.
Page | 479
NIOSH National Institute for Occupational Safety and Health have developed an “occupational lifting” formula to compute recommended weight limits. This has great influence on the health of the carrier. There are certain assumptions related to applying the NIOSH equation such as the temperature being favorable for lifting, smooth lifting and so on. The measurements required are shown from figure 7.17 the calculations are done for the origin and destination of a certain act. One could be safe, the other harmful. NIOSH can be applied manually or through a program from the following site “http:\\www.emcins.com\lc\niosh.htm”.
Figure 7.17: Diagram showing all the distances required to substitute into the equation.
Page | 480
The Recommended weight limit is calculated from the following equation: RWL = LC * HM * VM * DM * AM * FM * CM LI = W \ RWL
Where, RWL: Recommended weight limit
AM: Asymmetric multiplier
LC: Load constant
FM: Frequency multiplier
HM: Horizontal multiplier
CM: Coupling multiplier
VM: Vertical multiplier
LI: Lifting index
DM: Distance multiplier
W: Load weight
Note that, If the lifting index is less than one then the posture is fine for most workers. If greater than one then the job has to be redesigned and finally if it is greater than 3 then it poses a significant risk.
Figure 7.18: All the factors in the equation, and how each multiplier is calculated from the real data
Page | 481
Case description: Male worker is repetitively lifting 5-10 kg metal blanks from the slitting machine to the wilding machine.
Origin
Destination
Figure 7.19 Table 7.58: Multipliers.
Hand location
Origin
Angle
Vert.
Dest.
Freq.
Dist.
Origin
Dest.
Lifts /min
H
V
H
V
D
A
A
F
36
112
66
176
64
0
135
9
Time
hours
Object coupling
C 10
poor
RWL = 23 * (25/36) * (1- (0.003*|110-75| ) * (0.82 + (4.5/64)) *0.57 * 0.15*0.9 = 23 * (0.695) * (0.895) * (0.891) * (0.77) = 0.9815 ~ 1 Kg W (actual weight of object) = 5 kg LI = W/RWL = 5 / .9815
LI = W/RWL = 10 / .9815 = 10.188 > 3 (significant risk)
= 5.094 > 3 (significant risk) W (actual weight of object) = 10 kg Page | 482
Recommendation: Reccomendation: Join the slitting machine with the welding machine by a conveyor to eliminate the lifting operation.
SNOOK Tables Snook tables19 were originally published by Snook in 1978 and by Snook and Ciriello in 1991. Snook tables are used for lowering, lifting, pushing and pulling efforts. Snook tables are less precise than NIOSH since they are based on psychophysical measures rather than biomechanical. Data required include the type of effort, whether the job is carried out by a male or female, the distance moved, and the frequency. Appropriate tables are then used in order to reach the maximum acceptable force. Can Loading: Case Discreption: A male worker pulling a 30kg create filled whith 700 cans, each can weighing 400g, for 10 meters. The height of his hand is 1.3 m, and he repeats this process every 30 minutes. • Result: maximum acceptable weight is 28 kg. From Snook pull table results, it was concluded that the worker exceeded the weight limit. It is recommended a hoist is added to carry the crates from the loading machine to the sterilizing machine.
19
Figure 7.20
For more details about Snook tables, see Appendix (T)
483
Case Discreption: A male worker pulling a 32kg pallet for 3 meters, where the height of his hand is 0.7m, and he aproximatly does this process every 30 min. • Result:
maximum
acceptable
weight is 37 kg. From Snook pull table results; we can conclude that the worker did not exceed the weight limit. Figure 7.21
Page | 484
Rest Required in Minutes To find the rest required in minutes we use the equation: R = T [(W-S)/(W-1.5)] Where; • T: Total work time in min. • W: Average energy consumption of work in kcal/min. • S: Recommended average energy expenditure (4 or 5 kcal/min). Working hours in the factory: 10 hrs/day = 600 min 55 min/day break Total time = 600-55 = 545min. The rest required for the beans inspection belt workers: W = 1.6 kcal/min. R=545[(1.6 - 4)/(1.6 -1.5)] = 22.71 minutes < 55 minutes. Therefore, the rest time is acceptable. The rest required for the label inspector: W = 3.75 kcal/min. R=545[(3.75 - 4)/(3.75 -1.5)] = 60.5 minutes > 55 minutes. Therefore, the worker needs more breaks. Calculating the rest required for the final product stacker: W = 8.75 kcal/min. R=545[(8.75 - 4)/(8.75 -1.5)] = 350 minutes >> 55 minutes. Therefore, the job is very risky and the worker needs more rest. Page | 485
Discomfort Survey A survey20 was distributed amongst seventy workers to record the level of discomfort for each body part. It contained questions about the type of discomfort that they suffer and to which part of the body.
Discomfort Survey 21
20
11 7
7 5
5 3
3
3
2
2
2
R
ig ht Le low ft er lo le Le wer g M ft l id sh eg lo old w R er er ig b Le ht s ac ft ho k up ld pe er R ra ig ht rm t R ig Le high ht ft up thi p g Le er h ft arm f U or a p R per rm ig ht bac fo k R ra ig rm ht w Bu ris t to t ck s
3
Figure 7.22
The Pareto Chart results show that most of the workers are complaining from their right and left lower leg. Suggested tips to minimize injury risk during standing work: 1. Remember to move around. 2. Take breaks and stretch. 3. Watch your posture.
20
For more details, check Appendix (U)
Page | 486
7.6 Management Control
After analyzing the results of the checklist and the survey table, it was suggested a new, specialized department to the management system, which consists of: Departmental Safety officer (DSO). Safety Supervisor (SS). DSO responsibilities: 1. Apply and update OSHA regulations. 2. Develop training and refresher courses about safety and ergonomics. These courses include:
Instructions about using personal protective equipment.
Instructions about doing the job in a safe way.
3. Develop a monthly journal which will be distributed to the workers. These journals contain:
The accidents that occurred in the previous month, as well as the causes of the accidents, the suggested corrective actions and the suggested preventive actions.
An honors list, containing the names of the workers who are following the safety rules.
Useful safety and ergonomics information that benefits the workers.
Workers comments and answers to workers questions.
4. Develop Safety Manual 5. Organize occupational safety and health committee which consists of the supervisors of the factory shops. Also prepare regular committee meetings to monitor the workers’ safety performance. 6. Develop yearly safety reports to monitor the safety performance in both the filling line, and the can production line. 7. Develop monthly injury records.
Page | 487
Safety Supervisor responsibilities: 1. Investigate the factory using workplace safety checklists21. 2. Observe workers safety performance during working hours. 3. Apply training and refreshing courses to the workers. 4. Apply safety and ergonomics tools and analyze the results. In order to do their job properly, it is imperative for the DSO and SS to communicate with the other departments and workers regularly, to keep them informed of what is expected. These departments are: Management: 1. Approval on training courses. 2. Funding. 3. Assessment of staff requirements. 4. Reactive response to existing problems. 5. Funds for modifying existing equipment. Engineering department: 1. Evaluation
of
basic
workstation
design
and
making
appropriate
modifications to reduce or eliminate physical stress. Line supervisor: 1. Record important information, such as high risk jobs. 2. Identify production trends. 3. Supervise workers and eliminate any risky actions. Operators: 1. Attentive, open to new ideas, and asking questions. 2. Suggest improvements that might control the jobs’ physical stress. 3. Follow the company’s procedures for reporting an accident.
21
Provided in Appendix (P)
Page | 488
Purchasing department: 1. Purchase appropriate ergonomics equipment and tools. Maintenance department: 1. Maintain factory machines. 2. Maintain safety and ergonomic equipment and tools. Injury and Accident Record It is important for the company to have a well recorded medical injury and accident record because it helps in understanding what happened in an accident and why it occurred, which can lead to preventive actions in similar situations. Record keeping steps after an accident or an injury occur include: 1. Investigate the accident. 2. Compile data in a report. 3. Analyze the report. 4. Take preventive actions so that further accidents of the same type will not occur again. Keeping records will make it easier to point to the direct and indirect costs of an accident..
Direct Costs: o Medical expenses. o Replacement of damaged items. o Compensation paid to an injured employee. o … Etc.
Page | 489
Indirect Costs: o Lost time of injured employees. o Time lost on investigation, and preparing reports. o Damage to tools, equipment, materials or property. o Losses resulting from reduced productivity of injured workers upon return to work. o Loss of profit because of lost work time and idle machines. o Overhead costs that continue during lost work.
Also, laws and regulations that require record keeping and reporting injuries are other reasons for keeping records. At the same time, records help in identifying hazards, are used in establishing or adjusting insurance rates, and to assign legal penalties.
Page | 490
7.7 Conclusion In this project, the working conditions inside the factory were assessed. When possible, hazards were removed from the workplace to try and minimize the chances of workers sustaining significant injuries. This was done by applying multiple human factors tools as RULA and Snook pull/push tables, to eradicate any unhealthy postures during work or activities that cause too much fatigue to the workers. Of the 45 problems identified, 61% were ergonomic, 22% safety, 13% physical, and 4% were chemical hazards. It was found that 45% of the findings have exceeded the maximum acceptable lifting weight, body posture score, or maximum acceptable pulling weight. It is hoped that the company has been educated as to the important role that safety and human factors engineers can play in ensuring the safety of their workers and avoiding any expensive accidents from occurring.
Page | 491
References
Safety and Health for engineers, Roger L.Brauer (1994)
Human Factors in engineering and design, Sanders and McCormick- Seventh Edition
http:\\ google.com
http:\\en.wikipedia.org
http:\\www.emcins.com\lc\niosh.htm
http:\\www.cdc.gov\niosh\
http:\\www.rula.co.uk\
http:\\www.osha.gov\
https:\\www.ekginc.com\?p=services_ergonomics
http:\\www.ccohs.ca\oshanswers\safety_haz\materials_handling\
http:\\libertymmhtables.libertymutual.com\CM_LMTablesWeb\taskSelection.do?action=initTas kSelection
http:\\www.minerals.csiro.au\safety\physhaz.htm
http:\\www.saftek.com\osha\checklists.html
http:\\www.ccohs.ca\oshanswers\safety_haz\forklift\checks.html?print
http:\\www.labour.gov.on.ca\english\hs\guidelines\lifttrucks\index.html
http:\\www.labour.gov.on.ca\english\hs\alerts\i10.html
http:\\www.worksmartontario.gov.on.ca\scripts\default.asp?contentID=2-61&mcategory=health#H2
http:\\www.stayingalive.ca\fire_checklist.html
http:\\www.stanford.edu\dept\EHS\prod\training\checklist\index_inspection.html
http:\\www.safety.uwa.edu.au\forms\workplace_safety_checklist
http:\\www.worksafesask.ca\topics\hazards.html
http:\\www.safety.uwa.edu.au\policies#physical
http:\\www.ccohs.ca\oshanswers\
http:\\www.cdc.gov\niosh\docs\2004-101\default.html
http:\\www.managementsuLort.com\factorytoolbox.htm
http:\\bfa.sdsu.edu\ehs\index.htm (A
Page | 492
8. Facilities Planning
Page | 493
Page | 494
8.1 Introduction
Facilities' planning determines how an activity’s fixed assets best support achieving the facility objectives. In general, 20%-50% of total operating expenses are attributed to material handling. With effective facilities planning, the material handling costs can be reduced by at least 30%. In this project the layout of the National Canned Food Production and Trading Co. was studied with the aim of achieving the facility’s objectives, in order to best be able to manufacture its products and deliver them to its customers by analyzing the existing problems and if possible finding appropriate solutions. Enhancing the satisfaction of the objectives and relationships of the fourteen major departments was attempted. The function of each department and its relationship with the others was studied. The flow of raw materials, semi-finished products and final products between the departments was focused on.
Problem Statment
The following are the problems that were noticed regarding the current layout of the factory:
The machines are too crammed.
Pathways are obstructed.
Inventory spread throughout the factory.
Wasted Space.
Floor area not clearly visible.
Throughout this study, the feasibility of eliminating these problems was studied.
Page | 495
Objectives
The following objectives are what were aimed to be achieved throughout this study of the facility layout and the relationship and interactions that exists between the departments. A.
Minimize the cost of distance traveled.
B.
Smooth intradepartmental flow.
C.
Improve the overall aesthetics of the layout.
D.
Utilize space more efficiently.
Solution Approach
The current layout of the facility was studied and new layouts were proposed by using the RDM and CRAFT software. Both layouts were scored based on their ability to meet the criteria set in the objectives of the study, and the one that best met the criteria was chosen. The costs of adopting the new layout were justified by means of cash flow analysis.
Page | 496
8.2 Current Layout
Departments
1. Can Production; The can production department includes all the machines used to make the empty cans. After they are produced, an overhead conveyor is used to move the empty cans to the empty can storage department.
Figure 8.23: Seaming machine (part of the can production department).
Page | 497
2. Empty Storage Can; The produced empty cans arrive to this area by the overhead conveyors; they are palletized and kept until they are needed.
Figure 8.24: Empty cans in storage.
3. Storage and Mixing tanks; In the storage and mixing department, the beans are brought from the cold storage area and are soaked in the tanks with the all the additives necessary until they are ready to be taken to the hoppers in the raw material preparation department.
Page | 498
4. Raw Material Preparation; In this department, the beans are brought from the storage and mixing tanks and are left to soak until the beans are soft enough, and are then washed in the real washer and manually inspected for any defective beans.
Figure 8.25: Workers manually inspect the beans.
Page | 499
5. Can Filling and Coding; In this department, the empty cans are filled using a solid filler machine with the beans that come from the raw material preparation, and with brine using the liquid filler machine. The cans are then coded with the production and expiration dates by the coding machine.
Figure 8.26: Codes showing production and expiry dates.
Page | 500
6. Can Sterilizing; After the cans have been filled and coded, they are taken to the sterilizing department by crates. There, the cans are put in four rotaries which use steam to cook and sterilize the can.
Figure 8.27: Can Sterilizing Machine.
Page | 501
7. Labeling and Packaging; After the cans have been through the sterilizing department, they are moved by crates to the labeling and packaging department where the cans are manually transported, from the crate to the conveyor, by a worker. The cans go through the labeling machine, then each 12 cans are wrapped together and placed on a small box that the packaging machine makes. Every two boxes are placed on top of each other to form a carton.
Figure 8.28: Packed cartons wrapped in plastic.
Page | 502
8. Filled Cans Inventory Store: After the cans have been packaged into cartons of 24 cans, they are palletized and taken to the filled cans inventory store by a forklift.
Figure 8.29: Inventory Storage.
9. Labels Storage; The labels storage department is a small space where the boxes of empty labels are stored until they are ready to be used by the labeling machine. When needed, boxes of labels are transported to the labeling machine by a worker using a crate.
Figure 8.30: Labels moved from storage by crates.
Page | 503
10. Cold Storage Area; The beans are stored in the cold storage area until they are needed for production and are taken to the storage and mixing tanks.
11. Office; There is one office for one employee inside the can plant. It’s very small and is currently located next to the raw material preparation department.
12. Maintenance Room; The maintenance room is the room where all the maintenance tools and equipment are kept.
13. Water Treatment Room; The water treatment room is where the water that is to be used in the production line is cleaned and purified. It also supplies the water needed through pipes.
14. Vinegar Production Line; The National Canned Food Production and Trading Co. also produce vinegar. The vinegar production line is inside the can plant, and occupies a very small area.
Page | 504
Blue Print of Factory
Figure 8.9: Blue Print of the Factory.
505
As-Is Layout #5 Can Filling #10 Cold
#6 Can Sterilizing
and
Storage Coding
#13
Treat-
#8 Filled
#14 Vinegar
Line
Water
Cans
ment Room
Inventor
#4 Raw
y
Material
Storage
Preparatio n
#3 Storage
#1 Can Production 1.
#7 Labeling and
and Mixing
Packaging
Tanks
#2 Empty Cans
12.25 m
Storage #11
#12
Offic.
Main t.
Figure 8.10: As-Is Layout of the Factory.
#9 Labels inventor y Page | 506
As-Is Layout with dimensions
Figure 8.11: As-Is Layout of the Factory with dimensions.
Page | 507
As-Is Layout showing flow between departments
Figure 8.12: As-Is Layout of the Factory with dimensions.
Page | 508
Department Areas Table 8.59: Departments' Areas.
#
Department name
Area (m2)
1
Can Production
254.8
2
Empty Can Storage
107.8
3
Storage and Mixing Tanks
75.14
4
Raw Material Preparations
169.6
5
Can Filling and Coding
65
6
Can Sterilizing
147.6
7
Labeling and Packaging
171.15
8
Filled Cans Inventory Store
183.52
9
Labels Storage
43.4
10
Cold Storage Area
64.24
11
Office
6.25
12
Maintenance Room
6.25
13
Water Treatment Room
30.15
14
Vinegar Production Line
7.2
Total
1332.1
509
Grid Layout For the grid layout, all areas were rounded to the nearest 25m 2 Departments 10, 11 and 14 were ignored because they are not involved in can production/filling, and they are small. Table 8.60: Number of Grids.
#
Area (m2) Rounded # Grids
1
254.8
250
10
2
107.8
100
4
3
75.14
75
3
4
169.6
175
7
5
65
75
3
6
147.6
150
6
7
171.15
175
7
8
183.52
175
7
9
43.4
50
2
10
64.24
75
3
11
6.25
0
0
12
6.25
0
0
13
30.15
25
1
14
7.2
0
0
510
Each Grid represents 25m2
10
5
10
10
5
6
6
6
6
6
6
5
4
3
1
1
7
7
8
13
4
3
1
1
7
7
8
8
2
4
3
1
1
7
7
8
8
2
4
4
1
1
7
8
8
2
4
4
1
1
9
9
2 Figure 8.13: Grid Blocks representing the As-Is Layout.
Page | 511
8.3 Material Handling
The following are the material handling modes that were considered. They represent the way material andcans are moved from one department to the other. The material handling modes are described in more detail in section 4. Empty Can's Overhead Conveyors
Figure 8.14: Overhead Conveyor.
Conveyor
Figure 8.15: Conveyor linking raw material preparation department and can filling department.
Page | 512
Forklifts
Figure 8.16: Forklifts.
Crates
Figure 8.17: Crate.
Pipes: Flow through pipes was neglected because its cost represents a negligible proportion of the total costs.
Page | 513
Forklifts Material Handling Modes between Departments
Crates Overhead Conveyor Conveyor Can Making Flow
1
2
Can
Can Inventory
Production
Storage
Water Pipes Can Filling Flow 9
13
Label
Water
Storage
Treatment Room
10
3
4
5
Cold
Storage and
Raw
Can Filling
Storage
Mixing
Material
and Coding
Tanks
Prep.
11
12
14
Office
Maintenanc
Vinegar
e
Line
6 Can Sterilizing
7 Labeling and Packaging
8 Filled Can Inventory Storage
514
Table 8.3-Material Handling Modes.
1 2 3 4 5 6 7 8 9 10 11 12 13 14
1
2
3
4
5
6
7
8
9
10
11
12
13
14
―
conveyor
0
0
0
0
0
0
0
0
0
0
0
0
―
0
0
conveyor
0
0
0
0
0
0
0
0
0
―
forklifts
0
0
0
0
0
0
0
0
pipes
0
―
conveyor
0
0
0
0
forklifts
0
0
pipes
0
―
crates
0
0
0
0
0
0
0
0
―
crates
0
0
0
0
0
pipes
0
―
forklifts
crates
0
0
0
0
0
―
0
0
0
0
0
0
―
0
0
0
0
0
―
0
0
0
0
―
0
0
0
―
0
0
―
0 ―
515
Table 8.61: Average Number of trips or units per day.
1 1 2 3 4 5 6 7 8 9 10 11
―
2 96000 ―
(1)
3
4
5
0
0
0
0 ―
0 (3)
20
―
84000
(2)
0 84000 ―
(2)
6
7
8
9
10
11
12
13
14
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
(3)
0
0
0
20
0
0
0
0
120
0
0
0
0
0
0
0
0
―
120
0
0
0
0
0
0
0
(6)
0
0
0
0
0
0
0
0
0
0
0
―
0
0
0
0
0
―
0
0
0
0
―
0
0
0
―
0
0
―
0
(4)
(4)
―
(5)
39
―
1
12 13 14
―
N.B. (n) denotes that the data point will be explained in the Data Collection and Calculations section.
516
Table 8.62: Average Cost (KD) per trip or unit.
1 1 2 3 4 5 6 7 8 9 10 11 12 13 14
―
2 (7)
3.3E-06 ―
3
4
5
0
0
0
0 ―
(7)
0 0.0944 ―
3.3E-06 (8)
0 (9)
2.7E-05 ―
6
7
8
9
10
11
12
13
14
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
―
0
0
0
0
0
―
0
0
0
0
―
0
0
0
―
0
0
―
0
0 (10)
0.03068 ―
0
0
0
0
0
0
(10)
0.03068 ―
0
0.0944
0 (8)
0.0944 ―
(8)
(10)
0.03068
―
Page | 517
Table 8.63: Average Cost(KD) per day.
1 2 3 4 5 6 7
1
2
3
4
5
6
7
8
9
10
11
12
13
14
―
0.32043
0
0
0
0
0
0
0
0
0
0
0
0
―
0
0
0.28037
0
0
0
0
0
0
0
0
0
―
1.89E+00
0
0
0
0
0
0
0
0
0
0
―
0.45125
0
0
0
0
1.89E+00
0
0
0
0
―
3.68208
0
0
0
0
0
0
0
0
―
3.68208
0
0
0
0
0
0
0
―
3.68E+00
3.07E-
0
0
0
0
0
0
0
0
0
0
0
―
0
0
0
0
0
―
0
0
0
0
―
0
0
0
―
0
0
―
0
02 8 9 10 11 12 13 14
―
―
Page | 518
Data Collection and Calculations
Avg. Number of trips/units (1) 96,000 empty cans are produced in the can production department, and are moved by overhead conveyors to the empty can storage area. (2) 84,000 empty cans are moved to join the can filling and coding department through overhead conveyors. (3) 20 forklift trips are needed to move the raw materials needed from the storage and mixing tanks to the raw material preparation department. (4) 120 crate trips are needed to move the filled cans from the can filling and coding department to the can sterilizing department and from there to the labeling and packaging department. (5) 39 forklift trips are needed to move the cans to the final inventory storage. (6) 1 crate load trip is needed to move the required labels from the labels storage to the labeling and packaging department. Avg. Cost/trip or Avg. Cost/unit (7) Conveyor costs 0.3204 KD/day ; 3.33778E-06 KD/can. (8) Forklifts' drivers' average salary is KD 95.735 /month; (÷ 26 days/month) = 3.682 KD/day; (÷ 39 trips/day) = 0.094414 KD/trip. (9) Conveyor Costs 2.256 KD/day; 2.686E-05 KD/can. (10) Worker's (pushing crate) salary is 3.682 KD/day; (÷ 120 trips/day) = 0.030684 KD/trip.
519
8.4 Method 1: Relationship Diagramming (RDM) Method
The Relationship Diagramming Method is a procedure applied in many layout algorithms. It involves creating a relationship chart which identifies the priority of the presence of one department next to the other by using letters. Table 8.64: REL Key.
Letter
Relation
A
Absolutely Important
E
Essential
I
Important
O
Ordinary
U
Unimportant
X
Undesirable
The following REL chart was created by studying the flow between the departments and asking factory employees and management about the necessity of the proximity between each department and the others.
520
REL Chart Table 8.65: Deparment Relationships.
14. Vinegar
production line
13. Water treatment
room
12. Maintenance
room
11. Office
10. Cold storage
area
9. Labels storage
14. Vinegar production line
8. Filled cans
13. Water treatment room
inventory store
12. Maintenance room
7. Labeling and
11. Office
packaging
10. Cold storage area
6. Can sterilizing
9. Labels storage
5. Can filling and
8. Filled cans inventory store
Coding
7. Labeling and packaging
4. Raw material
6. Can sterilizing
preparations
5. Can filling and Coding
3. Storage and
4. Raw material preparations
Mixing tanks
3. Storage and Mixing tanks
2. Empty can
2. Empty can storage
-
storage
1. Can production
1. Can production
E
O
O
E
O
O
U
U
U
X
U
I
U
-
I
O
E
U
U
E
U
U
U
U
O
U
-
E
O
O
O
U
U
E
X
U
I
U
-
A
I
I
I
U
E
O
U
E
U
-
A
I
I
U
U
X
U
I
U
-
A
I
U
U
X
U
E
U
-
A
E
U
O
U
O
U
-
O
U
U
U
O
U
-
U
U
U
O
U
-
U
U
O
U
-
U
O
U
-
O
U
-
U -
521
REL Diagram
Figure 8.18: REL Diagram.
522
Relationship Diagramming Worksheet Table 8.66:REL Diagramming Worksheet.
1
2
3
A E
2,5
1,5,8
4,10
4
5
6
7
8
5
4,6
5,7
7,8
3,10,1
1,2
13
9
2
9
7
10
11
12
3,4
13
14
4,6
3 I
13
O 3,4,6,
3
2,13
6,7,8
7,8,13
4,8
4,5
4,5
4,13
5,6,7
1,2,11
3
1,3
1,3,11,1
9,13
7
5 8,13
13
4,7,13
13
3
2,7,8,9 10,11,1 2
U 8,9,1
6,7,9,1
8,9,1
9,12,1
9,10,1
2,9,1
2,10,12
1,3,10
1,2,3,4,
1,2,5,6
2,8,9,1
1,2,3,
0
0
2
4
2
0
14
11,12,1
5
7,8,9,1
0
4
5
14
11,12,1
14
14
12,1
4
6,10,11
1
12,14
5,6,7,
6,7,8,9
12,14
12,14
8
10,11,1
9,10,1
2
1
13
4
4
14
1,2,3,4,
14 X
11
11
11
11
1,3,5,6
523
Iteration 1 Start with department #5 since it’s one of the departments with the highest number of “A” relationships and it has the largest E relationships.
5
Figure 8.19: Iteration 1.
Iteration 2 Place department #6 because it has the highest number of “A” relationships with department 5.
6
5
Figure 8.20: Iteration 2.
The next iterations are based on the following ranking hierarchy: “AA”, “AE”, “AI”, “EE”, “EI”, “E*”, “II”, “I*”. Where * corresponds to “O” and “U”.
Page | 524
Iteration 3 From the table below, department #4 was selected. Table 8.67: Iteration 3.
Dept. 1 E5*6
Dept. 9 *5*6
Dept. 2 E5*6
Dept.
*5*6
10 Dept. 3 *5*6
Dept.
*5*6
11 Dept. 4 A5I6
Dept.
*5*6
12 Dept. 7 I5
Dept.
E6I5
13 Dept. 8 I5
Dept.
*5*6
14
4 6
5
Figure 8.21: Iteration 3.
Page | 525
Iteration 4 From the table below, department #13 was selected. Table 8.68: Iteration 4.
Dept. 1 E5*4*6
Dept. 10
E4*5*6
Dept. 2 E5*4*6
Dept. 11
*4*5*6
Dept. 3 E4*5*6
Dept. 12
*5*6*4
Dept. 7 I4I5
Dept. 13
E6E4I5
Dept. 8 I4I5
Dept. 14
*4*5*6
Dept. 9 *4*5*6
4
13
6
5
Figure 8.22: Iteration 4.
Page | 526
Iteration 5 From the table below, department #1 was selected. Table 8.69: Iteration 5.
Dept. 1 E5I13*4*6
Dept. 9 *4*5*6*13
Dept. 2 E5*13*4*6 Dept.
E4*5*6*13
10 Dept. 3 E4I13*5*6
Dept.
*4*5*6*13
11 Dept. 7 I4I5*13
Dept.
*5*6*4*13
12 Dept. 8 I4I5*13
Dept.
*4*5*6*13
14
4
13
6
5
1
Figure 8.23: Iteration 5.
Page | 527
Iteration 6 From the table below, department #2 was selected. Table 8.70: Iteration 6.
Dept. 2 E1E5*13*4*6 Dept.
E4*1*5*6*13
10 Dept. 3 E4I13*5*6
Dept.
*4*5*6*13
11 Dept. 7 I4I5*1*13
Dept.
*1*5*6*4*13
12 Dept. 8 I4I5*1*13
Dept.
*1*4*5*6*13
14 Dept. 9 *1*4*5*6*13
4
13
2
6
5
1
Figure 8.24: Iteration 6.
Page | 528
Iteration 7 From the table below, department #10 was selected. Table 8.71: Iteration 7.
Dept. 3 E4I2I13*5*6
Dept.
E2E4*1*5*6*13
10 Dept. 7 I4I5*1*2*13
Dept.
*4*5*6*13
11 Dept. 8 I4I5*2*9*13
Dept.
*1*2*5*6*4*13
12 Dept. 9 *1*2*4*5*6*13 Dept.
*1*2*4*5*6*13
14
10 4
13
2
6
5
1
Figure 8.25: Iteration 7.
Page | 529
Iteration 8 From the table below, department #3 was selected. Table 8.72: Iteration 8.
Dept. 3 E4E10I2I13*5*6
Dept.
*4*5*6*10*13
11 Dept. 7 I4I5*1*10*2*13
Dept.
*1*2*4*5*6*10*13
12 Dept. 8 I4I5*2*9*10*13
Dept.
*1*2*4*5*6*10*13
14 Dept. 9 *1*2*4*5*6*10*13
3
10
4
13
2
6
5
1
Figure 8.26: Iteration 8.
Page | 530
Iteration 9 From the table below, department #7 was selected. Table 8.73: Iteration 9.
Dept. 7 I4I5*1*3*10*2*13
Dept.
*4*5*6*10*13
11 Dept. 8 I4I5*2*3*1*10*13
Dept.
*1*2*3*4*5*6*10*13
12 Dept. 9 *1*2*3*4*5*6*10*13 Dept.
*1*2*3*4*5*6*10*13
14
7
3
10
4
13
2
6
5
1
Figure 8.27: Iteration 9.
Page | 531
Iteration 10 From the table below, department #9 was selected. Table 8.74: Iteration 10.
Dept. 8 I4I5*2*3*9*10*13
Dept.
*1*2*3*4*5*6*7*10*13
12 Dept. 9 E7*1*2*3*4*5*6*10*13 Dept.
*1*2*3*4*5*6*7*10*13
14 Dept.
*4*5*6*7*10*13
11
3
10
7
4
13
2
9
6
5
1
Figure 8.28: Iteration 10.
Page | 532
Iteration 11 From the table below, department #8 was selected. Table 8.75: Iteration 11.
Dept. 8 I4I5*2*3*1*9*10*13
Dept. 12
*1*2*3*4*5*9*6*7*10*13
Dept.
Dept. 14
*1*2*3*4*5*6*7*9*10*13
*4*5*6*7*10*9*13
11
3
10
7
4
13
2
9
6
5
1
8
Figure 8.29: Iteration 11.
Page | 533
Iteration 12 All other departments were randomly assigned since they have the same ranking code and they are not necessary in the can production/filling line. 3
10
7
4
13
2
9
6
5
1
14
11
8
12
Figure 8.30: Iteration 12.
Page | 534
8.5 Method 2: CRAFT
CRAFT (computerized Relative Allocation of Facilities Technique) is the first computer aided layout algorithm. It was introduced by Armour and Buffa in 1963. The input data is represented in the form of an initial block layout and flow and cost matrices. The main objective behind CRAFT is to minimize total transportation cost. CRAFT uses the input data and calculates the centroid of each department and the rectilinear distances between the centroids, then stores them in a matrix. It then determines the initial layout score by multiplying the from-to-chart i.e. the flow matrix, by the distance and cost matrices. Next, CRAFT aims to improve the layout by performing all-possible two-way exchanges, which involve switching the place of two departments, and three-way exchanges, which involve changing three. It selects the interchange that results in the least cost at each iteration, unless no further reduction in cost is possible. CRAFT was used to develop a layout alternative for the factory's current layout, if possible, resulting in lower material handling costs.
Page | 535
CRAFT Output Initial Layout
Figure 8.31: CRAFT Initial Layout.
Initial MH Cost (KD/day)
124.1587
CRAFT Alternatives
Figure 8.32: 2-way Exchange.
2-way Exchange MH Cost (KD/day)
94.50639
Page | 536
Figure 8.33: 3-way Exchange.
3-way Exchange MH Cost (KD/day)
110.7229
Figure 8.34: 2-way followed by 3-way Exchange.
2-way followed by 3-way Exchange MH Cost (KD/day)
94.50639
Figure 8.35: 3-way followed by 2-way Exchange.
2-way followed by 3-way Exchange MH Cost (KD/day)
74.18327
Page | 537
The best layout developed by CRAFT was using the 3-way followed by 2-way exchange method. This layout alternative was massaged and compared with the layout developed by the RDM method.
8.6 Comparison of Method 1 and Method 2: Massaged Layouts
A: CRAFT Alternative 10
2
2
2
1
1
1
12
10
2
5
5
1
1
1
10
13
4
5
6
1
1
3
4
4
4
6
1
1
8
8
3
4
4
4
6
6
11
8
8
3
7
7
7
6
6
14
8
8
7
7
7
7
9
9
8
Figure 8.36: Grid Blocks representing the CRAFT Alternative Layout.
\
Page | 538
B: RDM Alternative 2
2
9
9
6
7
7
2
2
3
5
6
7
7
8
1
1
3
5
6
7
7
8
8
1
1
3
5
6
7
8
8
1
1
4
4
6
10
8
8
1
1
4
4
6
10
1
1
4
4
13
10
14
11
12
Figure 8.37: Grid Blocks representing the RDM Alternative Layout.
After massaging both alternatives, the layouts were input into CRAFT to display the actual MH cost associated with our massaged layouts.
Page | 539
A: CRAFT Layout
Figure 8.38: CRAFT Alternative Layout.
CRAFT Layout MH Cost
50.52348
B: RDM Layout
Figure 8.39: RDM Alternative Layout.
RDM Layout MH Cost
79.45359
Page | 540
Prioritization Matrix The following evaluation criteria were selected to be used in comparing both layout alternatives in order to determine which is better. Each criterion was then compared to the other and a score was given based on how important each criterion was with respect to the other. Table 8.76: Weights used to compare the importance of each pair.
Weight 1 5 10 1/5 1/10
Meaning Equally Important Significantly more important Extremely more important Significantly less important Extremely less important
Evaluation Criteria: A. Minimize the cost of distance traveled. B. Smooth intradepartmental flow. C. Improve the overall aesthetics of the layout. D. Space utilization.
NB. Relative Weight = Row Totals/Total. Table 8.77: Prioritization Matrix.
A
B
C
D 5
Row Totals 21
Relative Weight 0.57
A
1
5
10
B
1/5
1
5
1
7.2
0.20
C
1/10
1/5
1
1/5
1.5
0.04
D
1/5
1
5
1
7.2
0.20
Column Total
1.5
7.2
21
7.2
36.9
1.00
Page | 541
A: Minimize Cost of Distance Traveled Table 8.78: Criterion A.
A
CRAFT
RDM 5
Row Totals 6
Relative Weight 0.83
CRAFT
1
RDM
1/5
1
1 1/5
0.17
Column Totals
1.2
6
7.2
1
A lower MH cost was associated with the CRAFT alternative.
B: Smooth Intradepartmental Flow Table 8.79: Criterion B.
B
CRAFT
RDM 10
Row Totals 11
Relative Weight 1.53
CRAFT
1
RDM
1/10
1
1 1/10
0.15
Column Totals
1.1
11
12.1
1.68
Based on the study of the flow between the departments, the alternative developed by CRAFT had a smooth flow, resulting in fewer overlapping flows.
Page | 542
C: Improve Overall Aesthetics of the Layout Table 8.80: Criterion C.
C
CRAFT
RDM 1/5
Row Totals 1.2
Relative Weight 0.17
CRAFT
1
RDM
5
1
6
0.83
Column Totals
6
1 1/5
7.2
1
The alternative developed by the RDM had more regular shaped departments than the alternative developed by CRAFT, therefore it was deemed to look better than the alternative developed by CRAFT.
D: Space Utilization Table 8.81: Criterion D.
D
CRAFT
RDM 1/5
Row Totals 1.2
Relative Weight 0.17
CRAFT
1
RDM
5
1
6
0.83
Column Totals
6
1 1/5
7.2
1
The RDM layout gathered all the originally wasted space into one area which the factory could then use parts of as storage instead of having to randomly store items throughout the factory.
Page | 543
Ranking Alternatives Based on Scores Table 8.82: Final Ranking of Alternatives.
A
B
C
D 0.03
Row Totals 0.81
Relative Weight 0.72
CRAFT
0.47
0.30
0.01
RDM
0.09
0.03
0.03
0.16
0.32
0.28
Column Totals
0.57
0.33
0.04
0.20
1.13
1.00
Table 8.83: Alternative Scores.
Alternative
Score
A
72%
B
28%
Based on the final score, the CRAFT alternative was considered to be the better choice as the new layout.
Page | 544
8.7 Proposed Layout #9 Labels inventory
#6 Can Sterilizing
#2 Empty Cans Storage
#7 Labeling and Packaging
#5 Can Filling and
#3 storage and Mixing Tanks
#8 Filled
Coding
Cans Inventor y Storage
#1 Can Production #4 Raw Material Prep. #13 Water
Room
Storage Area
#14 Vinegar
ment
#10 Cold
Line
Treat-
#12
#11
Main
Offic.
t.
Figure 8.40: Proposed Factory Layout.
Page | 545
8.8 Savings in Cost Table 8.84: Summary of Costs and Savings.
Material handling cost in initial condition
124.1587 KD/day
Material handling cost in proposed layout
50.52348 KD/day
Savings
59.3 %
Annual Savings
22,975 KD
Average Annual profit = 775911.15 KD.
Average Daily profit = 2487 KD (assuming 12 months, 26 working days).
Therefore, the average daily loss in production, for every day the factory has to stop working in order to change the layout will equal the average daily profit. Assuming it would take approximately 14 – 21 days to change the factory layout, it would cause a 34,818 - 52,227 KD loss in production, on average. Also, assuming productive labor are hired to do the job at an average cost of 2000 KD to change the layout, the total cost is between 37,000 – 55,000 KD.
22,975 KD 22,975 KD
0
1
2
22,975 KD
3
22,975 KD 22,975 KD 22,975 KD 22,975 KD
4
5
6
7
P= 37,000~55,000 KD
Figure 8.41: Cash Flow Diagram.
Page | 546
Taken P = 37,000 KD •
P = P + A(P/A, i=12%, n=2) = - 37,000 + 22,975(1.69) = 1,827 KD.
Taken P = 55,000 KD •
P = P + A(P/A, i=12%, n=3) = - 55,000 + 22,975(2.40) = 140 KD.
This change in layout is profitable in almost 2 years if 37,000 KD was invested in changing the layout and is profitable in almost 3 years if 55,000 KD was invested.
Page | 547
8.9 Conclusion
Facilities planning techniques were used throughout this study in order to propose a new layout that would minimize material handling costs, improve space utilization, allow a smoother interdepartmental flow, and improve the overall aesthetics of the layout. The factory was split into 14 departments while keeping in mind that every department contained a part of the production line that was inseparable.
Two methods were used to propose new, better layouts. To apply those two methods it was necessary to develop a relationship chart, which explains the importance of the existence of every department with respect to the other, to be used in the relationship diagramming method. The flow and cost of the flow between departments and the material handling modes, was also collected and used in CRAFT software.
The layouts developed by both methods were compared based on selected criteria and the best layout was chosen and massaged. The costs of changing the layout were justified showing it would be profitable in a couple of years.
Page | 548
9. Conclusion
Page | 549
Page | 550
General Conclusion
By applying IMSE tools on the problems faced at the factory, many improvements were achieved. To start off, the over filling of cans was eliminated. Proper quality control procedures including adequate documentation and statistically reliable raw material sampling plans were also introduced. Also, a safer, more ergonomic work environment was provided for the employees, in order to avoid significant injuries in the workplace and thereby minimize any compensation or repair costs associated with major accidents. By breaking down and analyzing all the costs of the company, areas of waste such as over filling of cans and disparately high transportation costs for some markets, were highlighted and minimized. Furthermore, after studying the current maintenance policies, new plans were proposed. By using Arena simulation software, it was proven that these new plans minimize the maintenance costs whilst increasing daily production. In addition, specialized inventory models, including the EOQ and EPQ, were introduced to optimize the company’s production plans and help meet the demand forecasted for the near future. Having noticed that the transportation costs were high, and that the company is struggling to meet demand, burdened by excessive overtime, distribution plans were developed in order to reduce transportation costs and increase production capacity. Finally, a new proposed layout was introduced to minimize material handling costs, utilize space more efficiently, and improve the overall aesthetics of the factory.
Page | 551