Cost of Quality Reduction in NEMA Coils Assembly Lines

Abstract

The Cost of Quality (COQ) is a proactive cost associated with a prevention investment needed to ensure requirements are met to avoid nonconformances. There are two components to ensure companies meet requirements: internal costs and external costs. The internal costs occur prior to delivery of goods and services, and external costs occur after delivery or shipment. In this paper, the focus is on COQ reduction for a production line in a manufacturing facility. The NEMA Coils area is one of the top assembly lines for the company. Improvement projects were needed in order to reduce recent influx in non-conformance and to accommodate high demands at both short-term and long-term horizons. Root cause analyses were carried out and, as a result, the top 5 defects were determined to be associated with incomplete molding, incomplete winding, wrong stamping, wire split, and bad winding. In addition, two of these defects contributed up to 50% of the total non conformances found at these assembly lines. A time study was performed in NEMA coils and process changes were carried out which resulted in new assembly lines layout. After implementation line capacity increased by 25%, the downtime was reduced by 20%, and the COQ was reduced by 34%. Key Terms ⎯ Cost of Quality; Root Cause Analysis; Nonconformance; Process Improvement.