Selecting machines and buffers in unreliable assembly/disassembly manufacturing networks

This paper formulates an optimal design model for assembly/disassembly manufacturing networks. The objective is to maximize production rate subject to a total cost constraint. Machines are chosen from a list of products available on the market, and sizes of the buffers are chosen within a predetermined range. Each machine type is characterized by its total cost of ownership, failure rate, repair rate and processing time. The buffers are also characterized by their total cost of ownership coefficients associated with the buffer size. To estimate assembly/disassembly network performance, a decomposition-type approximation is used. The optimal design model is formulated as a combinatorial optimization one in which the decision variables are buffers and types of machines. A genetic algorithm is proposed as an optimization technique. Numerical examples are used to highlight the benefit of selecting simultaneously the buffers and the machines.