背压对并列双支管内高压成形充模能力与壁厚的影响

Effects of Back Pressure on Die Filling Capacity and Wall Thickness of Parallel Double Branch Tube during Internal High Pressure Forming

为了探究并列双支管内高压成形过程中管件成形性能,本文采用数值模拟方法研究了背压对管件充模能力以及壁厚的影响。结果表明：在最大内压和轴向进给量不变的情况下,相比无背压冲头的加载路径,具有背压加载路径的并列双支管的充模能力提高5.6%,支管顶部最大减薄率降低39%,有效防止了管件破裂。背压加载路径有效提高管件的充模能力和延缓壁厚减薄,从而提高管件成形性能。随着背压冲头后退速度增加,并列双支管的充模能力基本不变,最大减薄率和支管高度增大。

In order to investigate the formability of the parallel double branch tube in the process of intemal high pressure forming, the effects of back pressure on the die filling capacity and wall thickness of the tube were investigated by numerical simulation. The results show that under the condition that the maximum internal pressure and the axial feeding remain constant, compared with the loading path without back pressure punch, the die filling capacity of the parallel double branch tube with the back pressure loading path is increased by 5.6%, and the maximum thinning rate of the top of the branch pipe is reduced by 39%, so as to effectively prevent the tube rupture. The back pressure loading path can effectively improve the die filling ability of the tube and delay the wall thickness reduction, thus improving the forming performance of the tube. With the increase of the back velocity of the back pressure punch, the die filling capacity of the parallel double branch tube is basically the same, and the maximum thinning rate and the height of the branch tube increase.