Deterministic ınventory models with non-perishable product: a comparative study

Today's business environments are increasingly competitive, so establishing inventory policies allows for greater permanence. The objective of this research applies a comparison of deterministic models of inventories, based on current policies, in search of the optimal method based on total costs. For its development an industrial company of the plastic sector in the city of Cartagena—Colombia was taken. An initial diagnosis shows that the company has not implemented an adequate inventory method based on variable demand. The proposed methodology develops four stages, (i) Description of the case study, (ii) Data collection and analysis, (iii) Processing of inventory model methods and (iv) Analysis of results. Validation was carried out in a practical way, initially in the laboratory and later on site. The findings established that the higher the number of orders, the higher the order costs and the total costs, and that the maintenance cost is zero when the volume of orders is high and increases as orders stabilise. Finally, a better inventory policy is obtained when operating with algorithms, mixed integer linear programming optimisation and discrete simulation with deterministic variables.