A method to enhance volume flexibility in JIT production control

The issue of strategic flexibility in manufacturing is reviewed to establish the links between output flexibilities and resource level characteristics. Through these links, and considering a JIT environment, the need for flexible Kanban determination is then recognised with respect to demand fluctuations in the marketplace. This is also confirmed through a review of the related literature. Based on this recognition, a method is proposed, using an integer linear programming technique, to flexibly determine the number of Kanbans for each stage of a JIT production system, minimising total inventory cost for a given planning horizon. The effectiveness of the proposed method is then examined and compared with the results for the conventional method of fixed Kanban determination. The comparison proved a cost advantage for the proposed method over the conventional method in fluctuating demand situations while the cost advantage increases with increase in demand fluctuations. The proposed method incorporates practical limitations for changing the number of Kanbans in any stage of production. This aspect of the method is also discussed in the paper.