Identification of manufacturing defects leading to rejection during manufacturing of stabiliser bar

The work in this paper will present a systematic and collective approach for quality improvement in stabiliser bar manufacturing units. The approach has been defined to identify manufacturing defects leading to rejection and to reduce it during manufacturing with the help of Juran quality tools. Data were collected from the manufacturing plant, which indicates that the defect rates were significant, ranging between 0.6% and 21% at various stages of production. The figure gave a clear indication that the number of defects could be significantly reduced to a few parts within the total production. This could be achieved if appropriate manufacturing practices were adopted with the aim of reducing the effect of manufacturing system variables that affects overall quality. A process inspection chart (PIC) has been introduced to monitor the defects. After regular monitoring, it has been found that the main rejection was due to threading. Main parameters that are responsible for threading rejection have been identified. Corrections have been done in the process, drawing and holding device of machine tool to reduce rejection. After three months of implementing changes, a 20% reduction in defects was achieved.