Investigation of maintenance assumptions for an automotive production line using simulation modeling

This research paper presents an interesting finding on assuming assembly line average MTTR/MTBF data to predict the line throughput. A simulation modeling study is presented here for an automated robotic automotive welding assembly line. The assembly line layout for this study consists of 10 assembly process stations involving material handling robots, welding robots, sealing, metal piercing, optical gauging, and unload stations. There is no buffers in-between the process stations. The parts are transferred by robot-t-robot “hand-off” process. This is completely an automated assembly line with no operator. The aim of this paper is to develop a simulation modeling for the welding assembly line. Also, develop various scenario analyses to investigate the effects of using the average, minimum and maximum Mean Time Between Failure (MTBF) and the Mean Time To Repair (MTTR) values to predict the assembly line throughput. The simulation model predicted results show that the average MTBF/MTTR value actually produces poor results. The simulation model results show that the productivity could be improved by 13% using the actual maintenance data instead of using average assumption data.