Buffer sizing of a Heijunka Kanban system

Heijunka is a key-element of the Toyota production system which levels the release of production kanbans in order to achieve an even production flow over all possible types of products, thus, e.g. reducing the bullwhip effect. In this paper we analyze a kanban controlled and heijunka leveled production system where the arriving demands are controlled and limited by a kanban loop. The production system is modeled as a queueing network with synchronization stations. The aim is to determine the optimal number of production kanbans, and thus the buffer size that guarantees a given service level.