This paper presents a model of PDC, developed in Arena® 5.0, which aims at providing information about the total time of the retrieving process as the system is working under unexpected situations. This time is influenced by several variables such as shelves dimensions, routing velocity and mass of the parts. Elaborated solutions are presented to model those variables emphasizing the route, which is considered as the main factor that influences the process time. The results obtained in simulations make understandable the dynamic system and are also capable of supporting managers in decisions such as estimating the required number of employees responsible to order consolidation. It is also possible to establish relationship among pattern flow and random movement for several sizes of companies.