Improvement of Material Flow in the Production and Supply Chain of ...

More documents

Recommendations

Info

There are many methods to measure reliability. The purpose of this section is to investigate and compare the assembly line reliability estimated from yield simulation model. Generally speaking, yield is a measurement of reliability. Yield is defined as the ratio of the number of usable devices after the completion of a production process to the number of devices at the beginning of a process (Kyungmee & Kim, 2008). Yield is related to the profitability of any production line. Predicting yield for new technologies is important to determine the cost to modify layout for the yield improvement (Kyungmee & Kim, 2008). Reliability will be estimated from the yield simulation model set in the first part of this chapter. Such reliability is more useful, than reliability estimated from field failure data (such as failure rate of production), for determining whether a reliability requirement will be met or not. The volume of production of the first three solutions has been simulated in section 4.3. The results shown in Table 4.7 and Table 4.9 indicate the reliability of the first and third solutions meet the requirement while the second solution will satisfy the reliability requirement by employing workers overwork three or four shifts. The reliability in the last two solutions is stochastic situation, because both of the solutions depend on the employees and workers’ performance are hard to forecast. So we can say that in the point of reliability the first and third methods are the best. Followed is the second method. The last two are disadvantaged methods. 4.4.3 Lead Time comparing “Lead time is the total time required to complete one unit of a product or service.” (Elsmar, viewed 2008) Lead-time is typically a product of: 1. The frequency with which dealer orders are submitted 2. The relative timing of dealer order entry and OEM order review activities 3. The time lag between order entry/acceptance and production 4. Order confirmation delays due to limitations posed by supply constraints, and whether the dealer has earned allocation of those constraints (Elsmar, viewed 2008). Analyze the lead time will help people to learn that reducing lead time contributes directly to improving Quality, Safety, Customer Satisfaction, etc. The consequences of longer lead times will often (David, viewed 2007): 1. Less dependable forecasts as these have to be made earlier; the long lead times make the manufacturer vulnerable to unforeseen changes and inaccurate demand forecasts. 2. Reduced production flexibility; i.e. greater difficulties to adjust to order changes 3. Higher levels of inventory; a manufacturer will account for the uncertainties 34
and unforeseen events by keeping safety stocks. The safety stocks assure the necessary flexibility; or rather they act as buffers for the lacks of flexibility in supply chain. 4. Miss some customers. Since all of the solutions discussed in this paper will help achieve the market requirement, the lead time will be reduced. It is evident that the third solution will reduce the lead time most since two new machines are invested as well as the repair time is reduced. For the first and third solutions, it is difficult to compare these two but both of them decrease the lead time. And they are better than the last two methods. Comparing the last two, it is easy to get the result that the forth one is better than the last one from the aspect of reducing lead time. So the order from the lead time view is that the third solution takes the first; then is the first and second solutions; and next is the forth solution; the fifth solution stands the fifth. 4.5 Results Based on the discussion above, a table is used to shown the result clearly. In this table, using the mark denote different levels. The number one gets five, number two gets four, then the third one gets three, the forth gets two, and the last one get one. After calculate the total mark of each solution, the solution with the maximal mark will be the best one. From the result shown in Table 4.10, the solutions focus on the bottlenecks get similar marks with higher records. So the core to improve current situation is managing to solve the problems of bottlenecks. Table 4.10 Comparison Results of Different Solutions Invest machines at station 8 and station 2 Invest machine at station8 & cut down TTR & three shifts overwork Invest machines at station 8 and 2 & cut down TTR Three shifts & cut down TTR Three shifts & more effective work time Cost 5 5 3 2 2 Reliability 5 3 5 2 2 Lead Time 4 4 5 2 1 Once the productivity is confirmed to reach the production volume demand in 2008, investigation in material flow among suppliers, the company and customers is taking place. In the next chapters, pitfalls in the supply chain will be investigated and suggestions in optimization will be given. 35
Page 1 and 2: ROYAL INSTITUTE OF TECHNOLOGY Impro
Page 3 and 4: Needs to be pointed out is that in
Page 5 and 6: TABLE OF CONTENTS ABSTRACT.........
Page 7 and 8: List of Tables Table 3.1 Descriptiv
Page 9 and 10: CHAPTER 1 INTRODUCTION OF THE RESEA
Page 11 and 12: 1.2 Present problems Haldex faces i
Page 13 and 14: CHAPTER 2 RESEARCH THEORY AND METHO
Page 15 and 16: mindset simply does not accurately
Page 17 and 18: the customers. Both of them are pri
Page 19 and 20: processing in station 5b. In the re
Page 21 and 22: After deleting the un-normal data i
Page 23 and 24: data of preassembly line accords wi
Page 25 and 26: Standard Deviation 68.49 Standard D
Page 27 and 28: Table 3.6 Values of Parameters of T
Page 29 and 30: line. In order to simplify the mode
Page 31 and 32: Table 4.3 Output Date Come From the
Page 33 and 34: Table 4.5 Current Production Volume
Page 35 and 36: Table 4.7 listed the simulation res
Page 37 and 38: 4.3.3 Increasing the operation time
Page 39 and 40: ottlenecks. Obviously, from the poi
Page 41: the first one. For the third soluti
Page 46 and 47: separately and the supply chain emp
Page 48 and 49: 5.2.1 Current distribution of suppl
Page 50 and 51: Table 5.2* Delivery Information of
Page 52 and 53: ecause this only gets from experien
Page 54 and 55: 5.3.2 Inventory and suppliers’ se
Page 56 and 57: Table 5.3 Integrative Estimation of
Page 58 and 59: CHAPTER 6 INVENTORY REDUCTION AND D
Page 60 and 61: How to get the best value from a su
Page 62 and 63: calculation, 420 pallets can be suc
Page 64 and 65: each day. The maximum load of one t
Page 66 and 67: and can also overworking during wee
Page 68 and 69: CHAPTER 7 CONCLUSION AND FUTURE WOR
Page 70 and 71: Reference Books and papers • Ahma
Page 72 and 73: y Chapman&Hall. • Vickery, Shawne
Page 74 and 75: Appendix A Table 1 TTF & TTR Data o
Page 76 and 77: Table 5.1 Suppliers & Suppliers’
Page 78 and 79: Appendix B Figure 1 Assembly line M
Page 80 and 81: Figure 3 Current Assembly Line Mode
Page 82 and 83: Figure 5 Assembly Line Model in Sol

Improvement of Material Flow in the Production and Supply Chain of ...

Create successful ePaper yourself

Delete template?

Save as template?