Mohsen Fathollah bayati - Department of Industrial Engineering, Iran University of science and technology
Morteza Rasti Barzoki - Department of Industrial & Systems Engineering, Isfahan University of Technology
Seyed Reza Hejazi - Department of Industrial & Systems Engineering, Isfahan University of Technology

The economic production quantity (EPQ) is a commonly used inventory model. While most of the work has been reported to explore the traditional optimal batch quantity in ideal cases, little appears to have been done with rework option In this paper products are classified in the four groups of perfect products, imperfect products, defective but rework-able products, and, finally, non-rework-able defective products. The percentage of each type is assumed to be constant and deterministic. The objective of this paper is to determine the economic production quantity and optimal number of cycles with rework and reject situations in a single-stage system in which rework is done after N cycles causing less than the desired quantity of good products in each cycle. The model has been validated with illustrating numerical example.

economic production quantity (EPQ), rework, reject