Economic Production Cycles with Imperfect Production Processes

TLDR

The production system deteriorates during manufacturing, yielding a proportion of defective items. The study investigates how imperfect, dynamically deteriorating production processes affect the optimal production cycle time. The authors extend the model to allow the defective rate to depend on set‑up cost, jointly optimize set‑up cost and cycle time, analyze linear, exponential, and multi‑state deterioration, and illustrate results with numerical examples. The derived optimal cycle time is shorter than that predicted by the classical Economic Manufacturing Quantity model.

Abstract

Abstract In this paper, we study the effects of an imperfect production process on the optimal production cycle time. The system is assumed to deteriorate during the production process and produce some proportion of defective items. The optimal production cycle is derived, and is shown to be shorter than that of the classical Economic Manufacturing Quantity model. The analysis is extended to the case where the defective rate is a function of the set-up cost, for which the set-up cost level and the production cycle time are jointly optimized. Finally, we also consider the case where the deterioration process is dynamic in its nature, i.e., the proportion of defective items is not constant. Both linear, exponential, and multi-state deteriorating processes are studied. Numerical examples are provided to illustrate the derivation of the optimal production cycle time in these situations.