螺栓预紧力对双端面磨床结构特性影响规律研究

Effect of Bolt Preload on the Structural Performance of Double-End Grinding Machines

摘要: 针对MD7660磁性材料双端面磨床在运行过程中出现的结构变形问题，本文提出了一种基于有限元方法的主要结构分析与优化策略。利用ANSYS Workbench建立了简化后包含床身、送料组件的整机有限元模型，通过静力学分析、模态分析和谐响应分析，深入探讨了预紧力对机床变形、应力分布、接触刚度及动态响应的作用机制。研究结果表明：当预紧力从1000 N增加到5000 N时，整机最大变形从0.153 mm降低至0.088 mm，降幅42.5%；连接面接触刚度从2.1 × 10⁷ N/m提升至8.9 × 10⁷ N/m，增幅305%；前六阶固有频率分别提升至68.3 Hz、88.4 Hz、100.7 Hz、172.6 Hz、199.5 Hz和257.3 Hz。综合考虑静态刚度、应力分布和动态特性，确定4500~5500 N为最优预紧力区间，该区间内应力分布最均匀，结构刚度最优。研究成果为双端面磨床的装配工艺优化和性能提升提供了理论依据。

Abstract: To solve the problem of structure deformation of MD7660 magnetic material double-end grinding machine during operation, this paper puts forward a main structure analysis and optimization strategy based on finite element method. ANSYS workbench is used to establish a simplified finite element model of the whole machine, including the machine body and feeding components. Through static analysis, modal analysis and harmonic response analysis, the action mechanism of preload on machine deformation, stress distribution, contact stiffness and dynamic response is discussed. The results show that when the preload increases from 1000 N to 5000 N, the maximum deformation of the whole machine decreases from 0.153 mm to 0.088 mm, with a decrease of 42.5%; The contact rigidity of the connection surface is increased from 2.1 × 10⁷ N/m to 8.9 × 10⁷ N/m, with an increase of 305%; the first six natural frequencies are increased to 68.3 Hz, 88.4 Hz, 100.7 Hz, 172.6 Hz, 199.5 Hz and 257.3 Hz respectively. Comprehensively considering the static stiffness, stress distribution and dynamic characteristics, 4500~5500 N is determined as the optimal preload interval, in which the stress distribution is the most uniform and the structural stiffness is optimal. The research results provide a theoretical basis for the assembly process optimization and performance improvement of double-end grinding machine.