Six Sigma Implementation on Wash Motor Twin Tub Washing Machine: A Case Study

Industrial Engineering Department, Faculty of Engineering, Universitas Sebelas Maret, Surakarta, Jawa Tengah, Indonesia.

^* Corresponding author: erysaaputri@gmail.com
^† Corresponding author: retnowulan@staff.uns.ac.id

Abstract

The competition of electronics and household industry in Indonesia is very tight, thus encouraging the industries to be more creative and innovative to attract customers. PT XYZ as a company that produces washing machines, especially twin tub washing machine, often experiences problems related to the quality of its constituent parts. Part refers to products manufactured by the supplier. One of them is wash motor, which still many of line drops in production line. Based on the calculation of the average DPMO (Defects per Million Opportunities) and the average sigma value in January 2023 were 251.69 and 4.99. This shows that the sigma level value of the company is between levels 4 and 5 which is in the position of the US industry average. The aim of this study is to reduce the number of defects in twin tub washing machine production using Six Sigma method through the Define, Measure, Analyze, Improve, and Control (DMAIC) phases. The results show that there are four dominant types of defects, namely rivet loose, rusty, noise, and no function. Five-M checklist determines suggested improvements based on man, machine, method, material, and environment factors. The Six Sigma approach has the opportunity to be used to support quality control activities to overcome defects that appear on wash motor and to improve product quality in washing machine factories by providing alternative approaches to suppliers.