Modified Economic Manufacturing Quantity Model for Product with Quality Loss under the Serial Production System and Rectifying Inspection Plan

The optimum process mean setting is an important method of modern statistical process control for determining the quality level. In 1994, Al-Sultan presented a single sampling plan applied in determining the optimum process mean for two machines in a serial production system. However, he didn’t consider the quality cost for the product within the specification limits, pointed out that the non-conforming items in the sample of accepted lot is replaced or eliminated from the lot, and proposed an integrated model with production and quality. In this paper, the author proposes a modified economic manufacturing quantity (EMQ) model based on a modified Al-Sultan’s model with k machines in a serial production system and asymmetric quadratic quality loss function for obtaining the maximum expected total profit per unit of time.