重切龙门镗铣加工中心结构静动态特性分析

Analysis of Static and Dynamic Characteristics of the Structure of the Heavy Cutting Gantry Boring and Milling Machining Center

为了在设计阶段精准评估重切龙门镗铣加工中心结构的动静态特性,建立加工中心整机结构有限元仿真模型,分析其静、动态特性。通过模态测试验证动态仿真模型的准确性和有效性,根据分析结果提出加工中心的结构优化建议。结果表明:由于滑枕的静刚度不足,导致加工中心Y方向的静刚度较低,在1 500 N切削力作用下,最大变形可达0.008 137 mm;加工中心的前6阶实测固有频率分别是41.87、55.69、88.06、103.45、129.68、159.41 Hz,前6阶固有频率的平均仿真计算误差为6.5%,立柱和滑枕位置在外部激振力作用下易发生较大的动态变形响应。

In order to accurately evaluate the dynamic and static characteristics of the structure of the heavy cutting gantry boring and milling machining center during the design phase,a finite element model was established for the entire structure of the machining center,and the static and dynamic characteristics as analyzed.The accuracy and effectiveness of the dynamic simulation model were verified through modal testing,and suggestions for structural optimization of the machining center were proposed based on the analysis results.The results show that the static stiffness in the Y direction of the machining center is low due to the insufficient static stiffness of the ram,under 1 500 N cutting force,the maximum deformation can reach 0.008 137 mm.The first six measured natural frequencies of the machining center are 41.87 Hz,55.69 Hz,88.06 Hz,103.45 Hz,129.68 Hz and 159.41 Hz,respectively.The average simulation calculation error of the first six natural frequencies is 6.5%.The positions of the columns and rams are prone to significant dynamic deformation response under external excitation forces.