模具约束条件对H96黄铜双脊矩形管E弯截面变形的影响

 双脊矩形管的绕弯成形受内外侧模具的共同约束,不同模具约束下管坯的受力不同,使得其截面变形情况也不相同,而截面变形严重地影响弯管件的成形质量和使用性能。因此,基于ABAQUS有限元平台建立了双脊矩形管E弯成形三维有限元模型,并通过实验验证了模型的可靠性。采用所建模型,研究了内外侧模具约束条件对双脊矩形管E弯截面变形的影响规律,发现当只有内腹板脊槽受约束时,内腹板脊槽的内缩变形可得到较好的控制,而其他部位的变形则有增大的趋势;当只有外腹板脊槽受约束时,内腹板脊槽宽度变形基本不发生变化,而其他部位的变形则有减小的趋势;当内外腹板脊槽均受约束时,可较好地控制双脊矩形管E弯过程中的截面变形。芯头个数对整管截面高度、宽度、外腹板脊槽宽度与两脊槽底部的间距的变形影响较大,但对内腹板脊槽宽度的变形影响不显著。

Influence of die constraint condition on cross-sectional deformation of H96 brass double-ridged rectangular tube in E-typed rotary draw bending process

The rotary draw bending process of the double-ridged rectangular tube is a complex nonlinear physical process with the internal and external die constraints. The stresses of the tubes under different die constraint conditions are different, which changes the situation of the cross-sectional deformation. And the deformation affects the quality and usability of double-ridged rectangular bending tube seriously. Then, based on the FE platform of ABAQUS/Explicit, the 3D-FE model is established for E-typed rotary draw bending of H96 brass double-ridged rectangular tube and validated by the experiment. Using the model, the influence of the internal and external die constraint conditions on cross-sectional deformation of the double-ridged rectangular tube in E-typed rotary draw bending process is researched. The results show that only when the inner ridge groove is constrained, the inner ridge groove shrinkage deformation can be better controlled, but other deformation is larger. Only when the outer ridge groove is constrained, the inner ridge groove width deformation does not change basically, but other deformation is smaller. When the inner and outer ridge grooves are both constrained, the cross-sectional deformation can be controlled effectively. The number of cores has more significant effect on the cross-sectional deformation, including the height and width of the global tube, the outer ridge groove width and the two ridge grooves spacing deformation, but has no significant impact on the width deformation of inner ridge groove.