Determining the optimal manufacturing tolerance for a single machine with deteriorating processing times

This paper examines a manufacturing system that deteriorates with machine age. The deterioration effect is shown as an increase on the rework percentage due to increased product quality rejection rates. Hence, the job processing time will be the planned time in addition to the rework time defined by total actual processing time of jobs in front of it in the sequence. The scheduling problem is intended to provide the optimal job sequence and manufacturing tolerance for quality characteristic. The objective of this work is to formulate a model that jointly determines the optimal sequence under deteriorating manufacturing times. Product rework economics will be considered explicitly in the model by using the quality loss function. More specifically, product outcome quality empirical relations will be considered in an explicit way in the sequence objective function.