某型号汽车波纹管液压胀形工艺参数优化研究

目的 探究波纹管液压胀形成形技术及液压成形过程,优化波纹管成形效果和减薄率.方法 基于正交试验方案,利用有限元技术对成形过程进行数值模拟分析,研究成形内压、轴向进给路径以及保压力对成形效果和减薄率的影响.结果 综合考虑成形高度、减薄率2个指标,得到的较优工艺参数为成形内压为2 MPa,保压力为1.25 MPa,轴向进给路径为在前0.1 s进给5 mm、后0.9 s匀速进给至模具闭合,此时成形高度为12.01 mm,减薄率为9.9％.结论 通过正交试验设计分析,轴向进给路径既是成形高度的显著性影响因素,又是减薄率的显著性影响因素;同时,单独优化一个指标(成形高度、减薄率)时,另一个指标性能会下降,根据正交试验优化结果选取最优参数组合进行模拟验证,得到的试验结果其综合成形质量较高.

Optimization of Hydraulic Bulging Process Parameters of a Certain Type of Automobile Bellows

The work aims to investigate the hydraulic expansion forming technology and hydraulic forming process of bellows, so as to optimize the forming effect and thinning rate of bellows. The effects of forming internal pressure, axial feed path and holding pressure on forming quality and thinning rate were studied by numerical simulation of the forming process with finite element technology based on an orthogonal test plan. Taking into account the two indicators of forming height and thinning rate, the optimum process parameters were obtained with an internal forming pressure of 2 MPa, a holding pressure of 1.25 MPa, an axial feed path of 5 mm in the first 0.1 s and a uniform feed in the second 0.9 s until the mould closed, at which time the forming height was 12.01 mm and the thinning rate was 9.9%. The orthogonal test design analysis shows that the axial feed path is a significant influence factor on both the forming height and the thinning rate; at the same time, when optimizing one index (forming height, thinning rate) alone, the performance of the other index decreases. The optimal combination of parameters is selected for simulation verification based on the orthogonal test optimization results, and the test results obtained are of high comprehensive forming quality.