Lot sizing in MRP with item sequencing: application in a PVC manufacturing business

Abstract

One of the many challenges faced by any organization is how to plan production, which, if done incorrectly, can result in machines lying idle during the production process. Previous studies that have investigated the effect of sizing in MRP batches did not consider the sequencing of items. This study investigates the effects of variations in the lot size on MRP and its effect on machine idle time during the production process of a company in the PVC industry. With the change of batch rule from lot-for-lot (L4L) to fixed quantity (EOQ), the company achieved a significant reduction in machine idle time. The results show the importance of considering the sequencing of the components on the study of the MRP and its impact on machine idle time. We concluded that the sequence of items in the production process should be considered when lot-sizing decisions for MRP are made.