Reducing defects in Mile line Of Rolling Plate Departement Using Six Sigma Method

Abstract

PT. Krakatau Posco is steel company that produces steel and distributes its products both for national and international market. PT. Krakatau Posco produces slabs and plates steel. In meeting the requirements of the markets, the high-quality products are a necessary, thus the company should improve their product quality by reducing defects. The purpose of this study is to identify product defects and to determine the factors that cause during the production process, to propose corrective actions to reduce the number of defects. This research was conducted at Mill Line on Plate Rolling Department PT. Krakatau Posco. The research uses the Six Sigma method. Following the Six Sigma method, the result of DPMO is 568 with δ value is 4.87 which is still under the world target which is 6δ (3.4 DPMO). Proposals steps for improving the quality of plate products are doing routine maintenance and repairing of the machine, checking engine calibration conditions, improving the quality of slab material, heating slab time > 180 minutes, setting parameters (thickness, width, and length) as specified, and checking the straightness of the product plate during the rolling process (camber correction). A post-publication change was made to this article on 20 Apr 2020 as an incorrect version was published.