带壁厚偏差管坯液压胀形加载路径的研究

建立了带壁厚偏差管坯液压胀形的力学模型,揭示了不同轴向应力状态下壁厚偏差对管坯成形的影响规律,给出了带壁厚偏差管坯液压胀形加载路径设计的标准.针对某重型卡车桥壳预成形管坯的液压胀形工艺,进行了3种不同壁厚偏差管坯在不同典型加载路径下的有限元模拟,结果表明:内压升高至最大保持恒定,管坯薄壁侧均在合模前发生开裂且薄壁侧与厚...

Research on the loading path of hydroforming for tube with wall thickness deviation

A mechanical model of hydroforming for tube with wall thickness deviation was established.The influence of wall thickness deviation on tube blank forming under different axial stress states was revealed.The standard for the design of the hydroforming loading path of tube blank with wall thickness deviation is provided.For the hydroforming process of the preformed tube blank of a heavy truck′s axle-housing,the simulation of three different wall thickness tubes under different typical loading paths was carried out.When the internal pressure increases to the maximum value and remains constant,the thin-wall side of the tube blanks cracks before die closing and the deformation difference between the thin-wall side and the thick-wall side is large.When the internal pressure increases first and then decreases,all the thick-wall side of the tube blanks are unstable to form folds and the deformation difference between the thin-wall side and the thick-wall side is small.When the internal pressure first increases,then decreases,and finally increases,the tube blank will be formed and meet the process requirements.The loading path suitable for hydroforming of tube blank with wall thickness deviation is determined.The hydroforming test was carried out on a special hydraulic press,and the obtained experiment results were consistent with the numerical simulation.