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Abstract The thin-walled cup is considered an important part of developing aeronautic, aerospace, rocket capsule components, military industry, and other manufacturing processes for daily use parts. These parts can be produced by conventional spinning with rollers or by ball spinning process. The recent development of ball spinning of tubes and thin wall thickness cups faces the challenge of limiting the large reductions due to built-up material formation in front of the forming balls. The current study introduces a new ball set design to overcome the pile-up problem during large reduction tube spinning. The proposed design consists of 4 balls distributed in four planes, having one ball in each plane. The first plane is set to suppress the pile-up formation, the second, the third, and the fourth planes are set for the main forming process. Every two consecutive planes are shifted by 90 deg. from each other to contribute to the thickness reduction. The new design is investigated experimentally through Latin Hypercube Design of Experiments. The surface responses of the experimental results are statistically analyzed using second-order linear regression. The results analysis shows that the new design has shown the potential to significantly overcome the pile-up formation in front of the forming balls at high thickness reduction operation. The optimum rotational speed of the mandrel with the optimum feed rate of tool regarding the process load were determined. The optimum working conditions for minimum material pile-up, minimum average diameter deviation percentage, minimum average thickness deviation percentage, and minimum average surface roughness Ra are determined and presented. |