Usulan Perbaikan Kualitas Menggunakan Metode Taguchi’s Loss Function dan Metode Fault Tree Analysis (FTA) untuk Meningkatkan Kualitas Produk Meja Lipat

Abstract

The manufacturing and service industries in Indonesia are currently experiencing increasingly competitive competition. The manufacturing industry is required to be able to produce good quality products in order to survive in competition. PT. Starindo Prima is a furniture manufacturing industry that produces wooden furniture products. One of the products with the highest demand at PT. Starindo Prima is a folding table. The problem faced by PT Starindo Prima, namely the varying thickness of folding table products which do not comply with the standards set by the company, namely 20 mm, which results in loss of quality. The aim of this research is to determine loss of quality and the factors causing it to improve the folding table production process using Taguchi's Quality Loss Function and Fault Tree Analysis (FTA). Analysis of variations in folding table thickness using Taguchi's Quality Loss Function method was carried out by calculating control maps and production capabilities. The control map shows that the thickness of the folding table is within the control limits with variations in the range of 19,380 mm to 22,108 mm. Calculation of the process capability index obtained Cp = 0.3522, indicating that the process has not been able to meet the specified standards. Based on calculations, a loss of quality of Rp. 187,835,840 per month for folding table products. Loss of quality of folding table products is caused by 2 main factors (top events), namely inaccurate measurements and inappropriate smoothing. Based on the Fault Tree Analysis of the two top events, it was found that the root causes of loss of quality from the top event, inaccurate measurement, were the operator's lack of focus, operator fatigue, the quality of raw materials not according to specifications, and lack of inspection of raw materials from suppliers, while from the top event, fine-tuning was not appropriate is that the measurement time is too short, the operator lacks focus, the machine is old, and maintenance on the machine is not carried out preventively.