A Study of Quality Costs in a Multi Component and Low Volume Products Automated Manufacturing System

In this paper, we illustrate how to design screening inspections for minimizing quality costs in a multi-stage automated manufacturing system. The total quality cost model consists of inspection costs, internal failure costs, external failure costs, and Taguchi’s loss function. Although, the use of an automatic test equipment such as machine vision and CMM (coordinate measuring machine) have greatly increased the inspection speed and its accuracy, screening (100% inspection) could be considered only as a short-term method to remove nonconforming items from the population, and not as a long-term quality improvement strategy. However, screening may be used before costly operations, or after unsatisfactory operations.