Improving the statistical process control chart by applying a DNOM chart for multiprocessor products

2nd International Conference on Engineering Sciences

Alkhafaji, Ahmed Abdulrasool^1 ; Al Obeidy, Nawres Qasim^1

Department of Mechanical Engineering, College of Engineering, University of Baghdad, Baghdad, Iraq^1

关键词: Lower specification limits;    Operation parameters;    Process capabilities;    Process capability indices;    Short-run production;    Statistical control charts;    Statistical process controls (SPC);    Upper specification limits;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/433/1/012068/pdf
DOI  :  10.1088/1757-899X/433/1/012068

来源: IOP

【 摘 要 】

Statistical control charts generally study only one property. The purpose of this research was thus to generate a control chart for a full set of properties for the product of the multiprocessors executing the operation of a lathe machine. In short-term production, there is often insufficient data in each product run to achieve an ideal estimate of operation parameters, which can result in reduced performance and inefficient control charts. A case study research methodology was applied in the Al-Noaman factory. Minitab-17 Software was used to calculate and plot control charts and to analyse the process capability index. The results of process capability (Cp) for three processes (drilling, face, and external length) were equal to 0.828, with the third process giving an external diameter equal to 0.248. Another index (Cpk) for shifting indicators, gave results for the lower specification limits for drilling and external diameter processes, while the other processes, face and external length, shifted towards the upper specification limit. The Cpm indicators showed the same behavior for Cp, and the Cpkm indicator gave results that suggested the same behavior as the Cpk.