重型等温锻造液压机刚度研究与检测

发布时间：2018-05-19 20:13

本文选题：液压机 + 应变片检测　；参考：《天津理工大学》2015年硕士论文

【摘要】：等温锻造液压机是大飞机、航空、军工制造业的基础设备,随着我国航空航天领域的快速发展,如何加工出符合需求的高精度钛合金锻件成为了一大难题。等温锻造液压机的制造就是为了完成钛合金模锻工艺的重要装备。而如何制造出高刚度的系列化机架装备尤为重要。本文以THP11D-20000为试验对象,对液压机刚度检测、有限元模拟、优化方案、模态分析进行了研究。1.对THP11D-20000等温锻造液压机进行检测,制定机身刚度检测规范,采用应变片检测刚度,对200MN重型数控超塑性等温锻造液压机样机进行联机检测,完成样机在不同载荷下的刚度检测,以验证重型整体组合框架式机身结构设计的可靠性。用数学方程的形式表达机身关键性部件的变形特征,得出非线性曲线。2.建立液压机—模具耦合模型,通过有限元分析法得到液压机在满载状况下的刚度、强度;并将有限元分析结果与试验结果相比较,通过对比所得结果可以验证出设计模型及模拟分析结果的准确性。3.通过对液压机两个重要的部件可改善参数的分析,分别在组合上下横梁确定下4个影响因素较大的优化变量。运用Box-Behnken Design(BBD)设计方法得出响应面模型的拟合方程及方差分析,并分别以挠度和质量为优化目标。上横梁挠度降低了0.256mm。下横梁挠度降低了0.012mm。上横梁质量降低了3.92 t。下横梁质量降低了39.31 t。4.对THP11D-20000等温锻造液压机进行模态分析。首先,介绍了有限元模态分析的概念、理论,再利用Workbench分别对液压机预紧状态和满载预紧状态下的整体机架进行有限元模态分析,得到了机架的前六阶模态的固有频率和相应的固有振型,并对各个状态下的前六阶固有频率和振型进行了详尽的分析和评价。机架整体的刚度和质量分布较为均衡,无明显的薄弱部位和过剩部位,只需在维保时注意大小拉杆的预紧力。地脚螺钉在五阶振型中出现应力交替变化的现象,材料可能会开裂或疲劳断裂。各阶固有频率都在5~17Hz,属于次声波范围,会产生一定的噪音,因此,应注意防护噪音污染。
[Abstract]:Isothermal forging hydraulic press is the basic equipment of large aircraft, aviation and military manufacturing industry. With the rapid development of aerospace industry in China, how to process high-precision titanium alloy forgings that meet the requirements has become a major problem. The manufacture of isothermal forging hydraulic press is to complete the important equipment of titanium alloy die forging process. And how to produce high rigidity serialized frame equipment is particularly important. In this paper, THP11D-20000 is taken as the experimental object. The stiffness test, finite element simulation, optimization scheme and modal analysis of hydraulic press are studied. The THP11D-20000 isothermal forging hydraulic press was tested, and the stiffness test criterion of fuselage was established. The strain gauge was used to detect the stiffness of the 200MN heavy-duty NC superplastic isothermal forging hydraulic press. The stiffness of the prototype was tested under different loads. In order to verify the reliability of heavy integrated frame structure design. The deformation characteristics of the key parts of the fuselage are expressed in the form of mathematical equation, and the nonlinear curve. 2. 2. The coupling model of hydraulic press and die is established, the stiffness and strength of hydraulic press under full load are obtained by finite element analysis, and the results of finite element analysis are compared with the test results. The accuracy of the design model and the simulation results can be verified by comparing the results. Through the analysis of two important parts of hydraulic press which can improve the parameters, four optimization variables with larger influence factors are determined under the combination of upper and lower cross beams respectively. The fitting equation and variance analysis of the response surface model are obtained by using the Box-Behnken design method, and the deflection and mass are taken as the optimization objectives respectively. The deflection of the upper beam is reduced by 0.256 mm. The deflection of the lower beam is reduced by 0.012 mm. The mass of the upper beam was reduced by 3.92 t. The mass of the lower beam is reduced by 39.31 t.4. Modal analysis of THP11D-20000 isothermal forging hydraulic press is carried out. Firstly, the concept and theory of finite element modal analysis are introduced, and then the finite element modal analysis of the whole frame under the preload state and the full load preloading state is carried out by using Workbench, respectively. The natural frequencies and corresponding natural modes of the first six modes of the frame are obtained, and the first six natural frequencies and modes are analyzed and evaluated in detail. The stiffness and mass distribution of the whole frame is more balanced, and there is no obvious weak part and excess part, only need to pay attention to the pre-tension force of the large and small strut during the maintenance period. The stress changes alternately in the fifth-order mode, and the material may crack or fatigue fracture. The natural frequencies of each order are at 5 ~ 17 Hz, which belong to infrasonic wave range and produce certain noise. Therefore, attention should be paid to the prevention of noise pollution.
【学位授予单位】：天津理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TG315

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