Production planning and scheduling for a plastic container and packaging company | |
| Author | Somporn Temudomsomboon |
| Call Number | AIT Thesis no.IE-89-24 |
| Subject(s) | Scheduling (Management) Production planning |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering |
| Publisher | Asian Institute of Technology |
| Abstract | This study concerns the development of production planning and scheduling models for a plastic container and packaging company in Thailand. The problems related to the production costs, high setup time machine and combination mold scheduling, and inappropriate inventory level are minimized by the developed procedures. First, the medium-range production planning model is developed to cover 6 months of planning horizon. Both fixed and variable combination molds are the major difficulty in the planning process. Developed lot-sizing heuristics cannot be applied to the problem because of the mold constraints. Thus, a mathematical programming approach is employed. To make the solution procedure possible, product classification made according to the demand patterns can help reduce the size of the problem. A Simple Plant Location Problem (SPLP) formulation is used for the aggregate production planning model because of its efficient computational time with the aid of a formatting program. Another model to serve the medium-range planning is the variable combination mold selection model of which the near optimal product combinations in the molds are determined. The problem is a quadratic non- linear mixed integer programming even after the number of molds in a period is fixed. An iterative heuristic approach is developed and some special characteristics of the problem are discovered. Analysis of the company's new policy which will eliminate this type of molds is carried out. Finally, a short-range planning model is developed to determine the production sequencing for day-to-day operations. A heuristic method is proposed and a computer program is coded to support the solution procedure. Although the comparison between the new methodology and the existing procedure is based on the result of only one instance because of the time constraint, the result reveals that the new methodology can improve the costs by about 5%. However, some other benefits can be achieved by the new approach. The more appropriate inventory level together with the new sequencing procedure can improve the customer service and reduce the job lateness. Significant reduction in setup times can indirectly increase machine capacity. This allows the company to serve customers with higher efficiency and more flexibility. Moreover, the new approach is computerized and based on the optimization techniques for which extension and modification can be made to cover other areas and situations in the factory. |
| Year | 1989 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Department of Industrial Systems Engineering (DISE) |
| Academic Program/FoS | Industrial Engineering (IE) |
| Chairperson(s) | Van Oudheusden, D.L.; |
| Examination Committee(s) | Tabucanon, Mario T.;Fujiwara, Okitsugu; |
| Scholarship Donor(s) | The Siam Cement Co., Ltd.; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1989 |