A new policy for EPQ regarding the quality of items, destructive inspection, and rework

One of the unrealistic assumptions of the economical production quantity model is the perfect quality the goods produced. To this end, following the previous attempts, in this paper it is assumed to have destructive inspections and existence of imperfect and rejected items after rework. In developed models, the new EPQ model has been calculated under 3 circumstances: 1- Imperfect items are not counted into the inventory after inspection, 2- The mentioned items are kept in the stock up to the end of production period within each cycle in EPQ model, 3- Aforementioned items are kept in stock up to the end of cycle. Moreover, we found out that if we use the traditional amounts instead of new ones, the total cost per unit time will increase with the same order. Finally, as sum of the fractions of imperfect and reworkable items ascend the EPQ and total cost per unit time will increase. A numerical example is applied to address the reliability of the results.