Increasing the output of mixed-model assembly lines for industrialised housebuilding: learnings from a case-based simulation study

In industrialised housebuilding, wall elements for on-site construction are prefabricated on mixed-model assembly lines with several workstations connected in series. The balance of a line is often disturbed by implementing new technical standards or product innovations, which makes it necessary to identify bottleneck stations and to analyse the effects of necessary activity adaptations. This paper presents the modelling requirements of this specific reconfiguring problem. A hybrid approach that covers configuration modelling and discrete event simulation is presented that links data describing product characteristics to processes of the simulation model. The use of controls provides a flexible and extendable production configuration environment for experiments, which can work with various activity assignments to stations. Several experiments were conducted, including worker flexibilisation, technical and process changeovers, a shift of work content between stations, and a combination of these scenarios and changes in the production programme. The performance of the production line can be increased in most scenarios, with the best results being achieved with flexibilisation measures that reduce the average production time per station by 13%. The results also show negative effects, if design options are offered to customers, that have an unfavourable impact on the balance of the production line.