【作者】 李增楼；

【导师】 赖一楠；

【作者基本信息】 哈尔滨理工大学 ， 机械设计及理论， 2011， 硕士

【摘要】 随着工业生产和科学技术的不断发展,管材的弯曲加工,在金属结构、工程机械、石油化工、动力机械以及锅炉、轻工、航空航天、管道工程等工业部门,占有着越来越重要的地位,也对管材的加工技术提出了更高、更新的要求。这就使得对管材弯成形质量缺陷的预测和控制成为研究与发展管材弯曲成形技术迫切需要解的难题。本文基于电站锅炉弯管,深入的进行了对数控弯管成形技术的相关问题的研究。在对国内外学者对数控弯管成形质量研究现状的分析基础上,分析弯管受力情况,建立数控弯管理论力学模型。介绍冷弯管加工过程,定义回弹角的计算;介绍塑性成形理论,分析塑性成形中的屈服准则、流动各向同性硬化、塑性本构关系以及推导了塑性求解过程;分析弯管过程受力分析,得到弯曲管件截面上轴向应力的分布,推导出了弯管回弹角的计算公式。通过对有限元分析中材料本构关系的确定、接触边界条件的处理、求解算法的确定等关键技术的处理,运用大型非线性有限元分析软件Marc,建立了数控弯管有限元模型。通过本模型的运算分析,可以对影响弯管成形质量和弯曲回弹量有影响的因素进行分析。实际应用表明通过改善这些因素可以来提高弯管的成形质量和得到准确的弯管成形角。在上述相关技术的研究基础上,本文基于成熟的商业软件VC++6.0集成弯管CAD/CAPP/CAE系统,成功加载了Proe二次开发模块、ansys有限元分析模块、CAPP工艺设计模块、Marc结果分析模块加载智能控制系统模块,开发了简单明了的人机界面,实现了CAD、CAPP、CAE之间数据无障碍传输,缩短了设计生产周期。更多还原

【Abstract】 With the development of industry production and technology , the processing of tube-bending has been more and more important in many industrial sectors such as structural hardware, engineering machine, power machine, boiler, light industry and aeronautics and space industry, but at the same time higher and more advanced tube-bending technology is required. The prediction and control of tube shaping defection and improvement of tube bending technology have become tough problems to be solved.This paper is based on the bending process of power station boiler tube, and I studied the relevant issues of NC tube bending technology in depth. I analyzed present researches of the shaping quality of NC tube bending from home and abroad, and based on these analyses, I analyzed the working condition of the tube when being bended and established the theoretical mechanics model of NC tube bending. I also introduced the process of tube cold bending, defined the calculation of the spring back angle, introduced the plastic forming theory, analyzed the yield criterion of plastic forming process, fluxion isotropic hardening, plastic constitution relationship and derived the plastic solve process. By analyzing the working condition of the tube being bended, I got the axial stress distribution on the section of the curved tube, and then derived the calculating formula of the spring back angle. The NC tube bending FEA model was built in large nonlinear finite element software--Marc by setting the material construction relationship of FEA method, handling the boundary condition, setting the solving algorithm and handling other critical technology. The factors that can influence the tube bending quality and the spring back quantity can be analyzed by arithmetic analysis of the model. And the practical applications shows that we can improve the shaping quality and the accuracy of the shaping angle by improve those factors. Based on studies of relative technology, the integrated CAD/CAPP/CAE bending system based on mutual commercial software–VC++6.0 has been developed, which has successfully loaded Pro/E re-develop module, FEA module based on ANSYS, CAPP module and result analysis module based on Marc, I also developed a simple human-computer interface. Data transmission without obstacles is realized by this integrated system and the design cycle was reduced.更多还原