Model Sequencing and Changeover Time Reduction in Mixed Model Assembly Line

Changeover time is a time between last good product of a specific model, to a first good product of another specific model. During this changeover time, materials, equipment and layout can be changed and this causes non-value added activities. This study aims the reduction of changeover time losses in the sixth line of a worldwide factory which produces combi boilers. Before developing the solution alternatives, causes of time losses were determined. After that, solutions have been searched with process design improvements. A simulation model and decision support system were generated to set the differences between proposed and current situation. While developing solutions, for specific symptoms, various technics were used such as 5S, Lean Manufacturing methods and Quality Function Deployment. Based on these studies, the current situation of the assembly line during changeover process has been improved.