Analytical methods for performance evaluation of transfer lines with shared repair capacity at Scania

Performance of real transfer lines is affected by several configuration parameters, like the size of the decoupling buffer areas and availability factors of the different machines. Indeed, machine availability is influenced by the nature of the machining operations performed, i.e. tool breakage, feeder problems, etc. and by the size and the skill of the repair crew in charge of the repair activity. Moreover, the capability of this repair crew is usually shared among different machines, and composed by repairman with different skills. In a collaboration project between Scania CV AB (Södertalje, Sweden), Politecnico di Milano (Milano, Italy) and KTH Royal Institute of technology (Stockholm, Sweden), we propose a new methodology, based on analytical methods, to evaluate the performance of transfer lines with shared repair capacity and different repairman skills. The application of this approach to the Scania six-cylinder engine-block machining line enabled a remarkable increment in system performance.