Analysis and optimisation of a network of closed-loop automobile assembly line using simulation

The work presented in this paper describes the development of a decision support system based on a discrete event simulation model. The model is aimed at a specific class of production lines with a four closed-loop network configuration of automobile assembly and preassembly lines connected by conveyors. The total number of pallets on the conveyors (which also act as intermediate buffers) remains constant, except for the fourth loop, which depends on the four-door car ratio implemented between the door disassembly and assembly stations of the car body. Some governing equations of the four closed loops are incompatible with the capacities of several intermediate buffers for certain values of the four-door car ratio. The simulation model can be used to assess the impact of variation in the length of the conveyors (hence, the size of the intermediate buffers) on the performance of the line. In addition, this paper also presents a proposal for the alteration of the length of the intermediate buffers that can maximise the performance of the production line and improve the availability of the manufacturing system for any value of four-door car ratio.