双连续弯曲半径铝合金管件推弯成形可行性分析

Analysis on push-bending feasibility of aluminum tube with double continuous bending radius

针对焊接结构降低双连续弯曲半径管件力学性能的缺点,提出利用推弯模具限制成形的特点进行该类管件成形,并对其可行性进行分析。根据单弯曲半径推弯的经验,设计双连续弯曲半径推弯模具型腔,在Forge 3D软件中建立有限元模型,分别模拟有、无内置芯模与管坯端头预倒角的3种工况的成形过程,并对模拟结果进行分析。研究结果表明,芯模和端头预成形分别起到支撑和引导金属流动的作用,两者缺一不可。结合良好工艺条件下的推弯验证试验可得,双连续弯曲半径铝合金管件推弯成形的横截面畸变能够得到有效抑制,该成形方法是可行的。

For the issues of mechanical properties decrease of the weld tube with double continuous bending radius, the push-bending process based on the characteristics of restraint forming by push-bending die was proposed, and its feasibility was analyzed. The die cavity of push-bending with double continuous bending radius was designed according to the experience of push-bending the single bending radius tube. The finite element model （FEM） was established by Forge 3D software, and three working conditions that with the inner mandrel, without the inner mandrel and chamfered end were simulated respectively, and the simulation results were analyzed. The results show that the inner mandrel can support the tube and the chamfered end can guide metal flow, either of which is indispensable. The push-bending test under the good bending conditions is carried out. The cross section distortion of the tube with double continuous bending radius by push-bending can be suppressed effectively, and the forming method is feasible.