Balancing inventory generated from a disassembly line: mathematical approach

Abstract

Product recovery is a new trend that many manufacturers practice to minimize the fast depletion of virgin resources and to realize economical benefits from recovering end-of-life (EOL) products. However, the practice of recovering components and materials is challenging as it often requires disassembly. There are many distinctive complications associated with the disassembly process. One of the complications stems from the disassembly line balancing problem (DLBP). DLBP has recently been actively researched in the literature and several heuristic models have been introduced to provide near optimal work contents at each workstation of the disassembly line. However, due to the disparity between demands for parts and their yields, there are many inventory problems that arise during the disassembly line balancing process. In this paper, we identify the issue of unbalanced inventories generated at various workstations of a disassembly line and discuss how to overcome this. A case example involving a personal computer (PC) is considered for discussion. In order to provide a full analysis of the problem, measures of performances are defined. Measures of performances reflect the state of the system and the ability to meet the demand while maintaining consistent flow of parts. We also discuss and compare various issues associated with the assembly systems and the disassembly systems. While it is clear that the inventory issues surrounding the disassembly line offer a new challenge, the understating that we have gained from solving the traditional inventory problems, nevertheless, provide helpful insights in overcoming this new challenge.