梁形零件等效建模方法及实验研究

发布时间：2018-05-02 03:27

本文选题：弯曲校正 + 等效建模　；参考：《中国矿业大学》2017年硕士论文

【摘要】：随着资源节约型、环境友好型社会的发展,再制造技术受到广泛关注。目前的再制造主要针对零件的表面修复。而针对变形零件的自动校正的研究较少。已有的校正理论的研究主要集中在少数几种具有规则截面的零件,这种方法不具有通用性。为此,本文针对梁形弯曲变形零件,通过等效建模,将复杂化的弯曲变形零件截面参数简单化,将多样化的校直模型统一化,为实现零件的自动化校正提供了理论参考。论文提出对称梁形零件的等效建模方法,以工型截面梁为研究对象,建立工型截面梁的等效矩形截面梁;分别建立工型截面梁及其等效梁的校正理论模型,得到各自的校正反弯曲率方程;进一步得到校正反弯行程,对比在相同初始弯曲程度下,工型梁及其等效梁的校正参数,验证该等效建模方法的可行性;最后,通过有限元仿真及实验进一步对等效建模方法进行验证。论文针对非对称梁形零件,以U型截面梁为研究对象,提出矩形度概念;基于矩形度,对U型截面梁进行等效建模,得到U型截面梁的等效矩形截面梁;基于矩形度,分别建立不同截面矩形度下的U型截面梁及其等效梁的校正模型,得到各自的校正反弯曲率方程,并进一步得到校正反弯行程;对比在相同初始弯曲程度下U型截面梁及其等效梁的校正参数,验证非对称梁形零件等效建模方法的可行性;最后通过有限元仿真和实验对非对称梁形零件的等效建模方法进行验证。论文提出变截面梁形零件的等效建模方法,以开槽变截面梁为研究对象,建立开槽变截面梁的等效矩形变截面梁;建立等效梁的载荷-挠度、载荷-残余挠度理论模型,并运用有限差分进行求解;分别对开槽变截面梁及其等效梁进行有限元仿真,通过对比等效梁有限差分法与有限元法的载荷-挠度以及载荷-残余挠度曲线,对建立的理论模型进行验证;通过对比有限元仿真中开槽变截面梁及其等效梁相同下压行程下的残余挠度,验证变截面梁形零件等效建模方法的可行性;最后通过实验对仿真结果进行验证。论文给出实验装置的结构设计方案;进行数据采集系统设计,对下压载荷及零件的弯曲程度进行实时监控;制作实验装置,分别对工型梁及其等效梁、U型梁及其等效梁、变截面梁及其等效梁进行三点压弯实验,验证等效建模方法的可行性。
[Abstract]:With the development of resource-saving and environment-friendly society, re-manufacturing technology has been paid more and more attention. Current re-manufacturing is mainly aimed at surface repair of parts. However, there are few researches on automatic correction of deformed parts. The existing correction theory is mainly focused on a few kinds of parts with regular cross section, this method is not universal. For this reason, through equivalent modeling, this paper simplifies the cross-section parameters of complicated bending deformation parts and unifies the various straightening models, which provides a theoretical reference for the automatic correction of the parts. In this paper, an equivalent modeling method for symmetrical beam parts is proposed. The equivalent rectangular section beam of the I-section beam is established, and the correction theory model of the I-section beam and its equivalent beam is established respectively, taking the I-section beam as the research object, and the equivalent rectangular cross-section beam of the I-section beam as the research object. The correct reverse bending stroke is obtained, and the correction parameters of the I-beam and its equivalent beam under the same initial bending degree are compared to verify the feasibility of the equivalent modeling method. The equivalent modeling method is further verified by finite element simulation and experiment. Taking U section beam as the research object, this paper puts forward the concept of rectangle degree, based on the rectangle degree, carries on the equivalent modeling to the U section beam, obtains the equivalent rectangular section beam of the U section beam, based on the rectangle degree, The correction models of U-shaped cross-section beams and their equivalent beams with different cross-section rectangular degrees are established, and their corrected inverse bending ratio equations are obtained, and the corrected reverse bending stroke is further obtained. The calibration parameters of U-section beam and its equivalent beam under the same initial bending degree are compared to verify the feasibility of the equivalent modeling method for asymmetric beam. Finally, the equivalent modeling method of asymmetric beam is verified by finite element simulation and experiment. In this paper, an equivalent modeling method for beam parts with variable cross-section is proposed. Taking the slotted beam with variable section as the research object, the equivalent rectangular variable section beam of the slotted variable section beam is established, and the load-deflection, load-residual deflection theory model of the equivalent beam is established. The finite element simulation of the slotted variable section beam and its equivalent beam is carried out, and the load-deflection curves and load-residual deflection curves of the finite difference method and the finite element method are compared. By comparing the residual deflection of slotted variable section beam and its equivalent beam under the same compression stroke in finite element simulation, the feasibility of equivalent modeling method of variable section beam is verified. Finally, the simulation results are verified by experiments. The structure design scheme of the experimental device is given, the data acquisition system is designed to monitor the pressure load and the bending degree of the parts in real time, and the experimental device is made, respectively, for the workpiece beam and its equivalent beam and its equivalent beam. The three point bending experiment of variable section beam and its equivalent beam is carried out to verify the feasibility of the equivalent modeling method.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TH16

【参考文献】