Assessing the assembly quality of a T-bar ceiling suspension by using an advanced multi-process performance analysis chart with asymmetric tolerance

Process capability indices (PCIs) are highly effective means for assessing the process potential and performance in manufacturing industry. However, the approaches developed for process capability indices (PCIs) can not analyse multi-process products. Some PCIs cause either the problems of sampling error of point estimates or full inspection. This paper aims to develop an advanced multi-process performance analysis chart with asymmetric tolerances (AMPPAC-AT) to assess the process performance of multi-process products. This approach takes into account interval estimates of the PCIs to overcome the shortcomings of full inspection or sampling error of point estimates. It can precisely measure an entire product composed of symmetric tolerances, asymmetric tolerances, larger-the-better, and smaller-the better characteristics. For application study, T-bar ceiling suspension system is handled to demonstrate the implementation process of AMPPAC-AT approach. We believe that our approach helps continuous improvement on overall assembly quality with asymmetric tolerances. [Received 19 March 2015; Revised 25 August 2015; Accepted: 22 September 2015]