Component commonality in closed-loop manufacturing systems

Much of the literature on forward supply chain management has focused on the importance of product design. In this research, we follow this approach and apply it to manufacturing systems in a closed-loop supply chain. We consider two closed-loop manufacturing structures: parallel and mixed structures. In the parallel structure, the assembly and disassembly are performed by separate lines, whereas in the mixed structure, they are performed by the same production line. We study effect of the use of a common component, the location of a common component, and the degree of delayed differentiation on the mean and variance of the cycle time for assembly (CTA). We find that the use of a common component significantly reduces the mean and variance of the CTA. The effect is pronounced when the variation in the disassembly service time is high, the structure is parallel, the utilization rate is high, the new-parts inventory level is low, and/or the return rate is high. Furthermore, placing the common component at the center of the manufacturing system yields the lowest mean and variance of the CTA. However, the effect is not statistically significant. Although increasing the degree of delayed differentiation significantly reduces the mean and variance of the CTA, the effectiveness is very sensitive to the process parameters.