共查询到18条相似文献,搜索用时 234 毫秒
1.
2.
3.
三通管内高压成形工艺研究 总被引:4,自引:1,他引:4
管件内高压成形工艺是近几年发展起来的一种新的塑性成形技术.本文分析了三通管内高压成形时的主要变形特点和技术关键,采用数值模拟方法给出了不同轴向进给速度下零件的壁厚及等效应变分布,并分析了轴向进给速度对成形性能的影响.分析结果表明,当轴向进给速度过快时,主管中部壁厚增厚严重,形成死皱.当轴向进给速度过慢时,主管中部容易导致变形区补料不足而破裂.因此轴向进给速度的选取对内高压成形三通管具有重要影响,对于成形TP2紫铜三通管,合理的轴向进给速度是0.5mm·s-1. 相似文献
4.
加载路径对X形管内高压成形质量至关重要,只有加载路径的各参数匹配得当,才能获得合格的成形件。利用DYNAFORM软件模拟不同加载路径下X形管的成形性能。并基于Box-Behnken Design试验设计和响应面法,以内压力、轴向进给量、背向位移量以及摩擦因数为试验因素,分别建立以最小壁厚、支管高度和极限圆角半径为目标的响应面模型。通过方差分析和回归方程分析,对X形管内高压成形过程的加载路径进行设计和优化,有效地改善了壁厚分布、减小了极限圆角半径、提高了支管高度。采用软件的数值优化功能筛选出最优的加载路径,并在此加载路径下对X形管内高压成形模拟结果和试验结果进行对比,发现误差在5%以内,并且壁厚分布具有一致性,说明了该加载路径优化方法具有较高的准确性和较好的可行性。 相似文献
5.
基于正交试验法的T型三通管内高压成形仿真与优化 总被引:1,自引:0,他引:1
针对T型三通管内高压成形过程中易出现的破裂和起皱等问题,为提升三通管的成形质量,选择最小壁厚与胀形高度等关键参数作为管件成形质量的评价指标。首先借助内高压成形设备开展T型三通管的实验研究,获取三通管成形的关键参数,并利用非线性软件DYNAFORM对T型三通管内高压成形过程进行仿真分析,通过与实验结果对比,验证有限元模型建立与仿真分析的正确性。基于此采用正交试验法对T型三通管的加载路径进行优化,提出所选工艺参数范围内的最优加载路径,通过实验验证了基于数值仿真与正交试验法获取加载路径的可行性与正确性,并为相关管件的内高压成形研究提供了参考。 相似文献
6.
7.
基于Dynaform软件平台,建立了Y型异径三通管三维弹塑性有限元模型。运用数值模拟方法,研究了AZ31镁合金Y型异径三通管热态内高压成形过程、成形缺陷、等效应变分布。探讨了初始管坯长度、左右冲头轴向进给量与成形支管高度之间的关系;研究得到了相同支管长度下成形不同Y型夹角三通管所需的左右冲头进给量。结果表明:随着初始管坯长度减小,支管高度随之增加;在左右进给量相同的情况下,左侧金属流向支管阻力更小,支管高度增加明显;随着Y型夹角的增大,右侧冲头进给增加,轴向补料比减小,总补料比增加,当夹角为90°时,左右补料相同。 相似文献
8.
9.
10.
内高压成形是以某种传力介质,使管材成形的一种现代塑性加工技术.与传统工艺制造出的三通管相比,内高压成形的异径三通管质量高(强度高、精度高),且成本低(减少成形和装配工序.本文进行了异径三通管内高压胀形的一系列实验研究,分析了异径三通管成形的主要影响因素,获得合理的工艺参数.结果表明,选用纯石蜡为胀形传力介质,成形结果较理想;几何尺寸也是较重要的参数;轴向压力为17MPa~22MPa、平衡压力为3.5MPa~4.5MPa时,成形效果较好. 相似文献
11.
Hydroforming process optimization of aluminum alloy tube using intelligent control technique 总被引:1,自引:0,他引:1
Ken-ichi Manabe Masamitsu Suetake Hiroshi Koyama Ming Yang 《International Journal of Machine Tools and Manufacture》2006,46(11):1207-1211
In this study, to determine the optimal loading path of tube hydroforming process, a database-assisted fuzzy process control algorithm proposed previously by the authors was applied to T-branch forming with a counterpunch. The tubular material used is aluminum alloy (A6063-T1) and has an outer diameter of 42.7 mm and wall thickness of 1.2 mm. Control variables is axial feed, counterpunch displacement, and internal pressure. The first two variables are dependent on the last one, which is an independent variable. In the control algorithm, new evaluation functions are adopted for buckling at the shoulder part of the branch and for contact fitting with a counterpunch. For a “virtual control system” including fuzzy algorithm with the evaluation functions, an explicit dynamic finite element code is used in the simulation. The experiments are carried out using a fuzzy controlled path obtained by the virtual control system, compared with the conventional manual control path that is attained by a trial-and-error approach. As a result, a T-branch product is successfully hydroformed. This result shows that the fuzzy control algorithm and virtual control system can provide an adequate loading path in the hydroforming process for an aluminum alloy tube. 相似文献
12.
S.J. Yuan C. Han X.S. Wang 《International Journal of Machine Tools and Manufacture》2006,46(11):1201-1206
An experimental and numerical simulation was conducted to investigate hydroforming of automotive rectangular-section structural components and the results were used as guidelines for some prototypes. The effect of loading path on the failures and thickness distribution was discussed and the reasons were analyzed for the failures, such as bursting and folding. Hydroforming with axial feeding is strongly sensitive to the loading path. Bursting occurs in transition zone in the calibration when the internal pressure increases faster than the axial feeding. Otherwise, folding will take place due to too much axial feeding. There is the maximum thickness at central point of the side of cross-section and the minimum thickness at the transition area. If the n value of the tube material is bigger, the thickness of the final part will be more uniform. By using a petal-like perform section shape, the pressure for forming the transition radii was greatly reduced and components with small radii can be formed with relatively low pressure. 相似文献
13.
14.
15.
Loading path optimization of tube hydroforming process 总被引:3,自引:1,他引:3
M. Imaninejad G. Subhash A. Loukus 《International Journal of Machine Tools and Manufacture》2005,45(12-13):1504-1514
Optimization methods along with finite element simulations were utilized to determine the optimum loading paths for closed-die and T-joint tube hydroforming processes. The objective was to produce a part with minimum thickness variation while keeping the maximum effective stress below the material ultimate stress during the forming process. In the closed-die hydroforming, the intent was also to conform the tube to the die shape whereas in the T-joint design, maximum T-branch height was sought. It is shown that utilization of optimized loading paths yields a better conformance of the part to the die shape or leads to a higher bulge height. Finite element simulations also revealed that, in an optimized loading path, the majority of the axial feed needs to be provided after the tube material yields under the applied internal pressure. These results were validated by conducting experiments on aluminum tubes where a good correlation between the experimental results and simulations were obtained. 相似文献
16.
空心双拐曲轴内高压成形数值模拟 总被引:1,自引:0,他引:1
应用动态显式有限元法对空心双拐曲轴的内高压成形过程进行了模拟分析,研究了加载路径对内高压成形的影响,指出了在加载曲线中存在着最佳成形区间,成形压力小于20MPa时,管坯产生起皱,成形压力大于32MPa时,管坯发生开裂,只有合理的应用加载路径,成形压力介于20MPa与30MPa之间,使轴向进给量可以正好补偿径向的变形量才能获得壁厚较为均匀的合格零件。 相似文献
17.
以薄壁Y形管为例,进行Y形管有限元建模。运用Dynaform有限元仿真软件进行内高压成形数值仿真,探讨Y形管成形规律、主要缺陷形式及缺陷产生位置;分析几何形貌参数、摩擦因数和加载路径等工艺参数对成形质量的影响。选取起皱间隙和贴模长度作为逻辑控制输入,评价成形状态;为优化Y形管内高压成形加载路径,将成形过程分为4个阶段进行模糊控制系统设计。结果表明:加载路径优化后,充模效果获得较大提升。将内高压成形工艺和模糊控制系统应用于某汽车排气系统Y形歧管,进行结构改进与成形工艺优化,获得了满足质量的合格零件。 相似文献