摘要
薄壁机匣的径向刚度低,在加工过程中易出现颤振,影响工件表面加工质量和加工效率。因此,设计了一种橡胶减振柔性夹具,其可大面积地支撑工件内壁,从而提高工件的加工刚度。建立了工件-夹具系统等效动力学模型,通过机匣铣削实验验证了模型的准确性。对比分析了橡胶减振柔性夹具与传统夹具的减振性能,研究了铣削力加载频率、压板压力、T形压板压力和推动块压力对工件-夹具系统的振动影响。结果表明:工件在采用减振夹具工况下加速度有效值相较于采用传统夹具减小了43.33%;采用橡胶减振柔性夹具后,工件可以避开400~900 Hz范围内剧烈振动的频率区间,振动幅度大大减小;随着压板压力的增大,工件加速度有效值先减小后增大;针对不同高度工件,应采用不同的压板压力,以减小加工过程中工件的振动;在实际加工中,T形压板压力应超过3.56 MPa,推动块压力应超过0.26 MPa,即液压缸推力超过20 kN。研究结果对橡胶减振柔性夹具的现场应用具有重要的指导意义。
Because of the low radial stiffness of the thin-walled casing, chatter is easy to occur during machining, which affects the machining quality and efficiency of the workpiece surface. Therefore, a rubber damping flexible fixture was designed, which could support the inner wall of the workpiece in a large area, thereby improving the processing stiffness of the workpiece. An equivalent dynamics model of workpiece-fixture system was established, and the accuracy of the model was verified by the milling experiment of the casing. The vibration reduction performances of rubber damping flexible fixture and traditional fixture were compared and analyzed. The influence of milling force loading frequency,pressure of platen, pressure of T-shaped platen and pressure of pushing block on the vibration of workpiece-fixture system was studied. The results showed that the acceleration effective value of the workpiece under the working condition with damping fixture was reduced by 43.33% compared with the traditional fixture;with rubber damping flexible fixture, the workpiece could avoid the frequency range of violent vibration in the range of 400-900 Hz, and the vibration amplitude was greatly reduced;with the increase of the pressure of platen, the acceleration effective value of the workpiece decreased first and then increased;for workpieces with different heights, different pressures of platen should be used to reduce the vibration of workpieces during processing;in actual processing, the pressure of T-shaped platen should exceed 3.56 MPa, and the pressure of pushing block should exceed 0.26 MPa, that was, the thrust of hydraulic cylinder should exceed 20 kN. The research result has important guiding significance for the field application of rubber damping flexible fixture.
作者
张姚
祝效华
董亮亮
ZHANG Yao;ZHU Xiao-hua;DONG Liang-liang(School of Mechatronic Engineering,Southwest Petroleum University,Chengdu 610500,China)
出处
《工程设计学报》
CSCD
北大核心
2022年第5期587-594,共8页
Chinese Journal of Engineering Design
基金
四川省科技计划资助项目(2019YFG0380)。
关键词
机匣薄壁件
铣削振动
减振夹具
动力学模型
thin-walled casing
milling vibration
damping clamp
dynamics model
作者简介
张姚(1996-),男,四川内江人,硕士,从事薄壁机匣加工振动研究,E-mail:1623977166@qq.com;通信联系人:祝效华(1978-),男,山东菏泽人,教授,博士,从事油气井管柱力学与井下工具研究,E-mail:zxhth113@163.com,https://orcid.org/0000-0002-0507-3773。
