In high-pressure die casting, various casting defects occur in serial production. To identify these defects, a comprehensive inspection process is necessary, including X-ray inspection, which is both time-consuming and demanding in terms of execution. The objective of this production process is to attain such control over the manufacturing process and its parameters that defective pieces are eliminated and X-ray inspection of entire serial production will no longer be necessary. The most significant quality issue encountered was the presence of porosity in the casting, which can be identified through X-ray inspection. By implementing the 6sigma method, we improved the tool pressures and consequently the quality of the casting. Additionally, utilizing the Taguchi method, we investigated the impact of the 3rd phase pressure on porosity formation in the casting. Through our research, we defined the appropriate process parameters that helped reduce the rejection rate to less than 5 % in 100 % X-ray inspection. Our findings revealed that the vacuum conditions and the condition of the casting piston have the greatest influence on porosity formation in the casting. Based on this knowledge, we transitioned from 100 % X-ray inspection to sample control. By adopting sample control, we decreased the production costs of each casting by 9 %. Furthermore, we enhanced process productivity by altering the lubrication of the pressure tool and reducing the cycle time by 23 %. After implementing all these process improvements, the manufacturing process is now effectively controlled, resulting in a total scrap rate, encompassing all work operations, of less than 7 %.
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