中文摘要：

基于Dynaform软件平台,建立Y型三通管热态内高压成形的三维弹塑性有限元模型。以左右冲头进给量、中间冲头后退量和内压力为因子,设计了正交试验方案,运用数值模拟分析方法,得到了三通管在不同加载路径下的支管高度和最小壁厚两个目标参数。探讨了各因素影响指标的主次顺序,采用综合平衡方法,获得了优化的加载路径。结果表明：通过优化的工艺方案可以得到综合质量较高的的Y型三通管。

英文摘要：

A 3D elastic-plastic finite element model for Y-shape tube heating hydroforming was established based on Dynaform software environment. Taking the left/right puncher pin feed, setback quantity of the mid- dle puncher pin and inner pressure as variances, a scheme for the orthogonal experiment was designed. With numerical simulation analysis method, the protrusion height and the minimum wall thickness of the three-way pipe in different loading path were obtained. The sequence of effects of various factors on the indexes is dis- cussed. The optimized loading path were obtained by integrated balance method and was confirmed bye FEM. The results show that the forming quality of Y-shaped tube can be improved with this method.