共查询到18条相似文献,搜索用时 156 毫秒
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介绍轴承座用冲压件代替铸钢件的制造方法,分析了冲压件轴承座的冲压工艺,提出了合理的成形工艺,对反拉深模结构设计、模具关键参数的选取以及模具工作过程作了阐述。利用限位装置成功解决反拉深起皱问题,保证了零件质量。 相似文献
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起皱和断裂是板料成形过程的主要失效模式,合理控制成形过程中的压边力,可以消除这些缺陷,提高成形性能。本文以圆锥形件的成形为例,采用Dynaform软件对变压边力控制的成形工艺进行了数值模拟计算,得到了最佳压边力变化曲线。本文还对模拟结果进行了实验验证。结果表明,变压边力拉深工艺能够极大提高板料的极限拉深高度。 相似文献
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数值模拟的双层金属板拉深成形工艺研究 总被引:1,自引:0,他引:1
某轿车排气歧管保护罩采用双层镀铝钢板同步拉深工艺制成,为获得最佳成形工艺参数,避免拉深时产生严重减薄及起皱现象,采用Dynaform软件对双层金属板同步拉深成形过程进行了有限元数值模拟,分析了压边力对拉深成形过程的影响,获得了不同压边力下保护罩内、外层板的壁厚减薄与增厚分布规律。结果表明,与单层板拉深成形相似,对于复杂型面双层金属板拉深件而言,单纯增加压边力并不能完全避免拉深过程中的起皱现象;采用压边力及合理布置拉深筋,可以保证内、外层板材料塑性流动均匀,有效抑制起皱、拉裂等缺陷。根据数值模拟结果进行了产品试制,获得了质量合格的拉深件。 相似文献
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基于Dynaform的汽车覆盖件拉延成形有限元模拟分析 总被引:1,自引:0,他引:1
基于Dynaform软件的基础,探讨了汽车覆盖件拉延成形过程有限元分析的关键步骤,重点研究了零件网格划分、工艺补充面建立、毛坯形状尺寸估算、拉延筋设置等关键内容以及模拟过程中应注意的问题。并利用Dynaform软件对该零件进行了拉延过程的有限元分析,根据模拟分析的结果,对拉延筋尺寸和分布方式以及工艺补充面的主截面线参数等工艺参数进行了优化调整,消除了拉裂及起皱现象,给出了相应的拉深工艺优化方案。 相似文献
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对向液压拉深是现代拉深成形工艺中的一项新技术。它利用凹模腔内液压室油液不可压缩的高弹性和油膜的高支撑强度及润滑性能,能有效地提高拉深件的形状精度、尺寸精度、成形件表面质量,提高成形极限,抑制侧壁起皱等拉深工艺缺陷。文章主要对对向液压拉深的液压系统设计及液压系统工作过程作了介绍。 相似文献
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以某半球形TA1钛合金拉深成形件为例,通过ABAQUS有限元软件建立了拉深成形三位模型和数值模拟正交试验方案。以是否破裂和起皱为衡量指标,探究凹凸模间隙、拉深速度和压边力对拉深成形件质量的影响,结果表明:起皱现象主要出现在压边区域不影响成形件质量,对底部最小厚度的影响从大到小依次为拉深速度、压边力以及凹凸模间隙。基于正交试验结果设计优化方案,得到最优工艺参数组合并将其应用于实际生产得到表面质量较好的拉深成形件,结果表明:基于正交试验对拉深成形工艺参数优化的方案可行,可以为企业生产提供指导,具有一定的工程应用价值。 相似文献
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Optimization of drawbead restraining forces and drawbead design in sheet metal forming process 总被引:1,自引:0,他引:1
H. Naceur Y. Q. Guo J. L. Batoz C. Knopf-Lenoir 《International Journal of Mechanical Sciences》2001,43(10)
This paper presents an optimization procedure of drawbead restraining forces in order to improve the sheet metal formability in deep drawing process. A simplified finite element method called inverse approach (IA) has been developed for sheet forming analysis with the consideration of the drawbead restraining forces. This IA is combined with a mathematical programming algorithm to optimize the restraining forces and then to design the drawbeads. The obtained optimization procedure is very efficient due to the simplified assumptions of the IA and the analytical sensitivity analysis. The Square cup of Numisheet’93 and the Renault Twingo dashpot cup are presented to demonstrate the usefulness of the proposed optimization procedure for industrial applications. Verifications of the obtained results have been carried out using a precise incremental commercial code OPTRISTM based on explicit dynamic approach to show the effectiveness of our approach. 相似文献
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Optimization of drawbead design in sheet forming using one step finite element method coupled with response surface methodology 总被引:1,自引:0,他引:1
Bingtao Tang Jixian Sun Zhen Zhao Jun Chen Xueyu Ruan 《The International Journal of Advanced Manufacturing Technology》2006,31(3-4):225-234
In a sheet forming process, drawbead plays an important role on the control of the material flow. In this paper, a numerical procedure for the design of forming processes is described. It is based on the coupling of an optimization technique and the simplified one step finite element method (also called inverse approach). The optimization technique allows adjustment of the process parameters so that specified criteria are fulfilled. Response surface methodology (RSM) is a global approximation method, which is ideally suited for solving highly nonlinear optimization problems. The finite element method, in addition to predicting the response of the process to certain parameters, allows assessment of the effect of a variation in these parameters on this response. The authors utilize the one step method at the preliminary design stage to supply stress or strain information for the following optimization using RSM. The procedure for this optimization process is fully described. The front fender for Numisheet 2002 is presented and the real defect free workpiece is produced to demonstrate the usefulness of the proposed optimization procedure. A comparison between the two forming limit curves (FLC) before and after optimization and results obtained using the precise incremental commercial software DYNAFORM based on the explicit dynamic approach verify that the optimization design method of drawbead could be successfully applied in designing actual tools of auto body cover panels. 相似文献
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The problem analyzed here is a sheet metal forming process which requires a drawbead. The drawbead provides the sheet metal enough tension to be deformed plastically along the punch face and consequently, ensures a proper shape of final products by fixing the sheet to the die. Therefore, the optimum design of drawbead is indispensable in obtaining the desired formability. A static-explicit Finite element analysis is carried out to provide a perspective tool for designing the drawbead. The finite element formulation is constructed from static equilibrium equation and takes into account the boundary condition that involves a proper contact condition. The deformation behavior of sheet material is formulated by the elastic-plastic constitutive equation. The finite element formulation has been solved based on an existing method that is called the static-explicit method. The main features of the static-explicit method are first that there is no convergence problem. Second, the problem of contact and friction is easily solved by application of very small time interval. During the analysis of drawbead processes, the strain distribution and the drawing force on drawbead can be analyzed. And the effects of bead shape and number of beads on sheet forming processes were investigated. The results of the static explicit analysis of drawbead processes show no convergence problem and comparatively accurate results even though severe high geometric and contact-friction nonlinearity. Moreover, the computational results of a static-explicit finite element analysis can supply very valuable information for designing the drawbead process in which the defects of final sheet product can be removed. 相似文献
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针对在覆盖件冲压成形领域对快速、自动化的有限元网格建模方法的迫切需求,提出一种快速的汽车覆盖件冲压仿真建模的思路与方法.将覆盖件冲压工艺设计与冲压成形仿真前处理集成,使用散乱三角面片模型,在自主开发的CAE前处理软件中,进行参数化的工艺补充面和压料面设计.模型的网格剖分与冲压工艺设计同时进行,自动生成整套模具的网格模型供冲压仿真计算.为了真实地模拟板料网格的流动,提出了参数化的真实拉深筋的模型建模方法和板料网格的预细分方法.完成了相关软件的开发.多个汽车覆盖件冲压工艺设计和冲压仿真计算实例说明了该方法的有效性. 相似文献
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主要讨论了用有限元逆算法进行钣金展开计算的方法,并用方盒和叶片的展开设计算例验证了这种方法的有效性。同其它的展开算法相比,有限元逆算法是一种计算精度较高,计算时间短的数值模拟工具。 相似文献