analisis pengendalian kualitas proses assembling busi untuk mencegah terjadinya defect menggunakan metode DMAIC di PT XYZ Indonesia

Abstract

PT. XYZ Indonesia is a company engaged in the automotive industry that produces several types of spark plugs. The problem that occurs in the company is that there are still defects in the production of LKR type spark plugs and there are several factors that contribute to the occurrence of defect products. The purpose of this study is to determine the factors causing the occurrence of product defects in the manufacture of LKR type spark plugs on the assembling line machine, knowing the sigma level that exists in the company at this time and after the repair phase. Based on the results of the study using the DMAIC method, the define stage is determining Critical to Quality where there are 3 CTQs, which are diameters of Mizo, Hexagon, and broken insulators, from the results of the Pareto diagram, the highest defect is 54.7% with a large Mizo diameter defect type. At the measure stage, initial measurements of control chart p, DPMO value, sigma level, and cost due to product defects are measured. In the analyze phase, which is to make fishbone diagrams and FMEA tables, it aims to find out the root of the problem and prevent it from causing the problem. After knowing the cause of this type of defect, improve phase is performed. Corrective action is applied based on the highest RPN value, namely changing the pressure parameters on the machine to adjust the condition of material quality, conducting additional training, making maintenance schedules, making or always updating the work instructions and putting it near the machine. As for the improvement phase, the sigma level is 4.157 σ, which means an increase of 0.018 σ. Next measure the cost due to product defects in the current condition of Rp. 844,825,000, and after the repair phase of Rp. 511,675,000 which means decreased costs due to defect products by Rp. 333,150,000.