
第42卷第5期 Vol.42No.5
假压技木
FORGING & STAMPING TECHNOLOGY
大型机床床身热变形及其结构优化
徐化文
(四川工程职业技术学院车辆工程系,四川德阳618000)
2017年5月 May 2017
摘要:在采用Pro/Engineer软件建立大型床身三维几何模型的基础上,运用Pro/Mechanica模块对该模型进行了热变形有限元分析,获得了热平衡状态下的床身温度场分布情况以及床身沿Y、Z方向的热变形量。依据分析结果,对床身的内部结构进行优化并增添外部冷却装置,然后再次进行热变形有限元分析和效果验证。在以上研究的基础上,进行了床身湿升与热变形实。研究结果表明,有限元分析值与检测值一致性较佳,经过优化设计的床身热变形量明显减小,既有效提升了工作效率,又降低了生产成本,使机床精度进一步提升。
关键词:大型床身;热变形;有限元分析;Pro/Engineer;机床精度 DOI: 10. 13330/j. issn. 1000-3940. 2017. 05. 015
中图分类号:TH122
文献标识码:A
文章编号:1000-3940(2017)05-0081-05
Thermal deformationand structure optimization onalargemachinebed
XuHuawen
( Vehicle Engineering Department, Sichuan Engineering Technical College, Deyang 618000, China)
Abstract: The three-dimensional geometric model of large machine bed was established by Pro/Engineer, and then the finite element analysis of thermal deformation was carried out by Pro/Engineer module. Therefore, both the distribution of temperature field for the machine bed under the thermal equilibrium state and the amount of thermal deformation for the machine bed along the Y and Z directions were obtained. The internal structure of the machine bed was optimized and an extermal cooling device was added based on the analysis re-sult. Furthermore, a finite element analysis of themal deformation was performed again, and the effect was verified once again. Based on the research above, the machine bed temperature rise and thermal deformation experiments were carried out. The results show that the ralues of finite element analysis and the detection are in good consistency, and the heat deformation of the machine bed designed by optimization is significantly reduced. With the improved working efficiency and the reduced production cost, the accuracy of machine is further improved. Key words : large machine bed; thermal deformation; finite element analysis; Pro/Engineer; machine accuracy
大型、重型装备制造是装备制造业的重要组成部分,在提升中国制造业整体水平上具有不可忽视的作用,也是我国由“制造大国”向“制造强国” 转变的必由之路。作为因轮加工装备中的基础部件大型床身在保证机床自身精度和零件加工质量方面的作用不容忽视。随着生产自动化和精密加工技术的迅猛发展,床身的精度以及精度的稳定性有了更高的要求。然而在长时间生产加工过程中,机床电机、机械运动部件、工件切削等会产生大量的热、这些热一部分会散发到空气中,另一部分会传递给机床本身,造成机床各部分的温升不均匀,出现温
收稿日期:20161216;修订日期:20170226 基金项目:四川省教育厅科研资助项目(16ZB0495)
作者简介:徐化文(1984-),男,硕士,讲师 E-mail: xuhuawen3@ 163. com
万方数据
度场并产生相应的热变形,最终对机床的形态精度和加工精度造成显著影响。其中,床身热变形是影响机床加工精度的重要因素,最高可达机床总加工误差的70%[1]
针对机床热变形对工件加工精度的影响,国内外众多专家学者进行了大量的研究工作[2-]。德国柏林工业大学运用有限元软件对机床部件及整机的温度场建立变形场模型并进行了分析(了。龚伟等运用三维软件Pro/Engineer对矩台平面磨床床身进行了精确的虚拟样机建模,并对该虚拟样机模型进行了热变形仿真,得出了机床变形的实测结果与仿真结果非常吻合的结论"」。李立新等从机床主要部件的结构出发,对机床热变形进行了简略推导,研究了机床热误差对刀具与工件间的相对位置的影响规律[9]。唐开勇运用几种不同的方法建立了导轨热变形的数学模型,既可方便数控编程,又可保证和提