Jurnal Sistem Teknik Industri
Vol. 28 No. 1 (2026): JSTI Volume 28 Number 1 January 2026

Quality Control Analysis Using the Seven Tools and Kaizen Methods to Minimize Terminal Defects in the Crimping Process

Al-Bar, Arba (Unknown)
Tjahyono, Rudi (Unknown)



Article Info

Publish Date
23 Feb 2026

Abstract

Product quality control plays a crucial role in maintaining competitiveness in manufacturing industries, particularly in high-volume production processes where minor defects can significantly affect product functionality. This study analyzes quality issues in the crimping process of wiring harness terminals at PT XYZ, where 1,170,016 terminals were produced over an eight-month period, resulting in 1,755 defective units (0.15%). The Seven Tools method including check sheets, histograms, scatter diagrams, control charts, pareto diagrams, fishbone diagrams, and stratification was employed to identify defect types and root causes. The analysis revealed that “too short” defects were the most dominant, accounting for 69.17% of total defects. The p-chart control chart indicated that the defect proportion fluctuated beyond control limits in several periods, signaling process instability. Furthermore, root cause analysis identified five main contributing factors: human, material, method, machine, and environment. Based on these findings, improvement proposals were formulated using the Kaizen approach through the Five-Step Plan and Five-M Checklist, focusing on standardization, training, preventive maintenance, and workplace organization. The proposed improvements are expected to enhance process stability, reduce defect occurrence, and support continuous quality improvement in the crimping process.

Copyrights © 2026






Journal Info

Abbrev

jsti

Publisher

Subject

Control & Systems Engineering Decision Sciences, Operations Research & Management Engineering Industrial & Manufacturing Engineering

Description

Jurnal Sistem Teknik Industri (JSTI) of Universitas Sumatera Utara, Faculty of Engineering, Department of Industrial Engineering, was published in 1998. Until now, the number of publications has reached 21 volumes, each of which is published by TALENTA Publisher twice a year . Each volume has two ...