Optimization of spinning process parameters for the large-diameter thin-walled cylinder based on the drum shape

Thinning spinning has the advantage of enhancing the performance of a product, and it is an effective method for manufacturing large-diameter ultrathin cylindrical parts. However, the rigidity of a large-diameter ultrathin wall cylinder is poor, the spinning process and forming quality are sensitive to the process parameters, and the drum-shaped result of the spinning process is prone to instability, which can cause the spinning process to be unbalanced. Therefore, it is a great challenge to select the appropriate process parameters for achieving the long-range stable spinning of large-diameter ultrathin wall cylinders. Based on the analysis of the thin-walled cylinder spinning mechanism, this study analyzed the effects of key process parameters on the drum shape of a C-276 thin-walled cylinder spinning process by serial experiments. The results of serialization experiments show that the thinning rate has a great influence on the spinning process state, the feed rate is secondary, and the speed has the least influence. On the basis of experimental analysis, the optimized process parameters of thin-walled cylinder spinning are obtained by using the support vector machine method: the wall thickness reduction rate cannot exceed 45% in single-pass spinning; 30~40% is a reasonable choice interval; the feed rate can range from 0.8 to 1.0 mm/r; and the rotation speed can range from 80 to 100 r/min. Finally, a comparative experiment and stability test of thin-walled cylinder thinning spinning over a long range is carried out, which verifies that the optimized spinning parameters can be used for the long-range stable spinning of large-diameter ultrathin cylinder parts.