多工位级进模模具结构偏载分析及优化设计

发布时间：2018-01-01 03:06

本文关键词：多工位级进模模具结构偏载分析及优化设计　出处：《华南理工大学》2016年硕士论文　论文类型：学位论文

【摘要】：随着高强板在汽车等行业内的广泛应用,对多工位级进模结构强度的要求也越来越高。因高强板的屈服强度高、成形性能差,冲压过程中大型多工位级进模受力更加复杂恶劣,容易造成模具结构偏载、损毁、失效等问题。因此,有必要针对大型多工位级进模模具结构进行受力分析和结构优化设计,特别是对于受侧向力较明显的凸模需进行偏载分析,以判断凸模侧向位移是否会影响成形质量。对于大型复杂多工位级进模,工件尺寸大,冲孔、修边、整形等工序的分布较分散,工作部分会采用组合子模的方式安装在模具母体上,模具母体在冲压过程中会产生较大的变形,严重影响工件的制造精度,造成产品冲压质量不稳定,从而延长了修模试模的时间,继而降低了模具的生产效率。因此,对多工位级进模的母体进行结构分析,以保证模具强度、刚度、减小冲压时模具结构变形为目标进行优化设计,实现材料的最优分布,达到模具结构轻量化的效果,具有非常大的实用价值。本文以某油箱支架件为研究对象,通过对其多工位级进冲压成形及冲裁工序进行数值模拟,获得了板料与模具之间的接触力,将该接触力应用至多工位级进模结构进行受力分析,提取出侧向力并进行偏载分析,在此基础上对模具母体结构进行拓扑优化设计。研究内容如下:(1)对某油箱支架结构件多工位级进冲压成形工序进行有限元数值模拟。基于CAE分析软件Dynaform对成形工序进行有限元建模,完成成形工序的数值模拟,通过对*dyn文件中的控制输出文件进行修改,获得出板料上各节点的成形力模拟结果,并提取出凹凸模所受侧向力信息。(2)对某油箱支架结构件多工位级进冲裁工序进行有限元数值模拟。基于CAE分析软件Deform-3D对冲裁工序进行建模,建模时通过预先对板料刃口附近区域进行网格细划分、减小网格规模,获得了准确的模拟结果。完成了该油箱支架结构件多工位级进冲裁所有工序的数值模拟,得到了各个工序冲裁力的模拟结果,并与冲裁力的理论计算值进行了对比分析,提取出冲裁工具与板料的接触力。(3)针对冲压过程中凹凸模受侧向力作用,将数值模拟获得的侧向力作为力的边界条件对凹凸模进行偏载分析。利用结构分析软件HyperWorks对该多工位级进模上模结构和下模结构进行受力分析。借助本项目组自主开发的载荷映射工具,将冲压载荷准确映射到模具结构分析有限元模型上。多工位级进模的零部件数量多,结构复杂,为提高运算效率,可适当简化模型,如可将浮料板和氮气弹簧进行简化。利用结构分析求解器Radioss完成对模具结构的受力分析。(4)基于变密度法对该油箱支架结构件用大型多工位级进模模具结构进行了拓扑优化设计。根据结构受力分析结果设定优化目标,以减小模具变形为目的,实现材料的最优分布。基于拓扑优化结果,综合考虑模具干涉、落料、加工制造等因素,在UG中对模具结构进行重构。为了验证重构后的模具结构强度是否满足要求,再次对重构后的模具结构进行受力分析,并与原结构变形量进行对比。结果表明,优化重构后的模具结构变形有所减小,模具减重约19%。(5)基于应变电测法对模具结构的应变值进行了取点测量,并与结构分析模拟结果进行了对比。结果表明,测量值与模拟结果的相对误差普遍较小,相对误差在10%以内。因此,本文所采用的多工位级进模结构分析方法是准确的,进而保证了多工位级进模结构拓扑优化结果的可靠性。
[Abstract]:With the wide application of high strength steel in automotive industry, the requirements of multi position progressive die structure strength is more and more high. Because of the high strength in high yield strength, poor formability, the stamping process of the large multi position progressive die stress more complex, easy to cause the mould structure of partial load, damage, failure so, it is necessary for large multi station progressive die structure stress analysis and structural optimization design, especially for the convex die under lateral force obviously require partial load analysis, to determine whether it will affect the lateral displacement of the punch forming quality. For large complex progressive die, the workpiece large size, punching, trimming, distribution is more dispersed shaping process, working parts using a combination of sub module is installed in the die, the die will produce large deformation during the stamping process, seriously affecting the workpiece precision manufacturing The degree of product quality is not stable, resulting in stamping, thus extending the model repaired time, then reduce the mold production efficiency. Therefore, analyzing the structure of the matrix of multi position progressive die, to ensure the mold strength, stiffness, reduce stamping die structure deformation for optimized design, to achieve the optimal distribution materials, achieve the lightweight mold structure effect, has great practical value. This paper takes a tank bracket as the research object, through the progressive stamping and blanking process by numerical simulation, obtained the contact force between the blank and die, the contact force applied at station level progressive die structure stress analysis, extraction and analysis of lateral force of eccentric load, on the basis of the die structure design of topology optimization. The contents are as follows: (1) of a fuel tank bracket structure progressive punching Pressure forming process numerical simulation by finite element analysis software Dynaform CAE. A finite element model of the forming process based on the complete numerical simulation of forming process, modified by controlling the output file of the *dyn file, get out of the forming force of each node of the sheet on the simulation results, and extract the die by lateral force information. (2) of a fuel tank bracket structure of progressive blanking process numerical simulation by finite element analysis software Deform-3D. CAE blanking process modeling based on modeling by pre on the sheet area near the edge of the grid partition, decreasing the grid size, obtain accurate simulation results. The numerical simulation of the fuel tank bracket structure of progressive blanking process all the simulation results are obtained in various processes of blanking force, and the calculated values were compared with the blanking force theory, extract The contact force of punching tool and sheet. (3) according to the stamping process of bump die under lateral force, the numerical simulation of lateral force obtained as force boundary conditions on the embossing die for partial load analysis. Using the software HyperWorks of the multi position progressive die mold structure and mold structure of the force analysis of structural analysis. With the help of load mapping tools developed by the project team, will load accurately mapped to the stamping die structure analysis on the finite element model. The parts multi position progressive die number, complex structure, in order to improve operation efficiency, may be appropriate to simplify the model, such as the floating plate and the nitrogen spring is simplified. Structure analysis of Radioss solver to analyze stress of die structure. (4) the variable density method of the fuel tank bracket structure for large multi station progressive die structure for topology optimization based on the design. According to the structure stress points The results of analysis to set the optimization goal, in order to reduce the mold deformation for the purpose of achieving the optimal distribution of materials. The results of topology optimization based on the comprehensive consideration of the mold interference, blanking, machining and other factors, to reconstruct the mold structure in UG. In order to verify the reconstructed mold structure strength meets the requirements of the mold structure reconstruction again after the stress analysis, and compared with the original structure deformation. The results show that the optimization of die structure reconstruction after deformation is reduced, the mold weight about 19%. (5) strain electrical measurement method of the die structure were taken based on the measurements and the simulation results are compared and analyzed. The results show that the structure the measurement value is generally small, the relative error of the simulated results with relative error less than 10%. Therefore, the multi position progressive die structure analysis method is accurate, and the multi position progressive die The reliability of the structural topology optimization results.

【学位授予单位】：华南理工大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：U466;TG385

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