Reducing non conformance quality of yarn using pareto principles and fishbone diagram in textile industry

摘要

Non Conformance quality of yarn in the Ring Spinning machine is high unevenness (U%) on the yarn. Unevenness is a measure of yarn quality which states the amount of mass deviation per length, whose existence cannot be avoided. This paper focuses on improving quality, by using pareto and fishbone analysis to solve problems. Through the loepfe sensor on the winding machine, it can be observed that there are Yarn with high unevenness that cannot pass through the sensor and cannot winding. After test using Uster Tester 5, it can be seen that the yarn has an unevenness percentage 10.74% compare with a standard is 9.92%, which means that the quality of unevenness is high and quality deviations occur. It can be seen in the Spectrogram mass that the area of unevenness occurs in the area of 10 cm-1 m with the source of information received from the quality control (QC) and maintenance of the area occurs in the technical or machine parts, namely on the top roll in the Ring Spinning machine. Through technical observations it was found that the top roll surface was uneven and this was the cause of the high level of unevenness in the P/V 30's Yarn. The solution to solve this case is a technical solution by grinding the top roll. Through this settlement, the quality improvement of the unevenness of the Yarn can be seen again from the Uster Tester 5, where the unevenness rate has decreased to 9.28% and the figure is included in the classification of yarn uneven quality standards.