Construction of Process Quality Assessment Model for Ratchet Torque Wrench  
Author Chun-Min Yu


Co-Author(s) Tsang-Chuan Chang; Kuen-Suan Chen; Huo-Tsan Chang


Abstract This paper conducts a case study on ratchet torque wrenches and develops an assessment and verification model of process quality as a means of assisting hand tool manufacturers in managing the quality of ratchet torque wrench products and promoting the on-going development in the hand tool industry. We first propose the process quality index (PQI) that can directly determine a precise level of quality based on the relationship between various process capability indices and Six Sigma quality levels. Using inference, we further develop a testing model of PQI to evaluate the quality level reached of process performance. The present case study is investigated to illustrate the practical applicability of the proposed method.


Keywords Hand tools, ratchet torque wrench, process quality index, quality level, statistical inference
    Article #:  22022
Proceedings of the 22nd ISSAT International Conference on Reliability and Quality in Design
August 4-6, 2016 - Los Angeles, California, U.S.A.