Storage assignment of (semi-)finished products in an environment with multiple plants, warehouses, and production lines

Abstract

Manufacturing systems are becoming increasingly complex with the involvement of several plants, dozens of production lines, and thousands of different SKUs. Products have to be stored between the production stages, and the export to the end-users. Within this context, storage assignment decisions are crucial in order to reduce the number of handling. This report considers an integrated approach of several streams of literature and methods to capture the characteristics of the system under study. The literature disciplines are storage assignment, ABC inventory classification, routing problems, and cross-docking. By means of a simulation with several heuristics, and multi-criteria decision-making with the application of the best-worst method, several storage policies and products-oriented rule sets are tested. The findings indicate that considering product features in the storage assignment, provides better performance on the number of handling, storage time, and meeting the due date. Particularly favouring important products results in a higher performance on these goods as well as on the overall performance of the system. The sensitivity of the multi-criteria policy is tested with disruptions in the production process, and the outcomes show that the performance even increases. Future research could integrate the products-oriented rules for the storage assignment and picking, and also with a possibility of relocation. Moreover, the equipment's (train and crane) could be included.