Assessment of layout solutions for restructuring a manufaturing process

Planning the layout of machining and assembling departments is a common problem for mechanical industries that aim at improving their production performance. Indeed, the relation between complicated layouts and poor productivity has been confirmed by several studies. In this respect, two key decisions are the precise positioning of machines and the planning of buffer capacity. Several approaches to layout analysis have been proposed: some employ optimization techniques taking into consideration traditional performance measures, while others are based on more recent management concepts, such as lean manufacturing or quick response manufacturing, and use heuristic methods or simulation. The paper presents a study carried out in a manufacturing company which produces ship engines, focused on two departments: component machining and module assembly. The study examined a project for material flow improvement based on lean manufacturing concepts and tools. In particular, the Value Stream Mapping was employed, which allows analyzing the “as-is” and outlining the “to-be” situations, eventually leading to the redefinition of the production layout. In accordance with the waste minimization principle, it was decided to realize a new warehouse with a capacity lower than the pre-existing one. Such decisions, however, required to minimize the congestion of the internal routes, in order to supply the needed material at the right time with an adequate fleet of forklift trucks. To validate the effectiveness of the foreseeable results and understand the behavior of the entire production line, varying some parameters and the new truck fleet in place, a simulation model was carried out, which allowed to establish the operational feasibility of the proposed solution.