Economic Lot Scheduling for Two-Product Problem

In this paper we propose an algorithm for the two-product single machine Economic Lot Scheduling Problem (ELSP). Past research on this problem has relied heavily on the assumption that both products are produced cyclically. In particular Boctor's algorithm provides optimal solution to the two-product problem under such assumption. We first simplify Boctor's algorithm and then propose an algorithm which allows for the unequal cycle time for the more frequently manufactured product. We show that the cost corresponding to our solution is either less than 1.015 times the cost obtained from the Independent Solution, which is a lower bound of the optimal solution, or is better than that obtained by Boctor's algorithm. An example is used to show that the difference in cost can be as much as 24%.