基于不同加工工艺的微孔节流空气静压轴承的特性研究

Study on the Characteristics of Micro-hole Throttling Aerostatic Bearings Based on Different Processing Methods

随着超精密加工技术和地面微低重力仿真的发展,相关产业对空气静压轴承的性能要求越来越高。由于传统的孔式节流器其结构特点不能完全满足实际使用的需要,节流孔直径与气膜间隙同一数量级的微孔节流空气静压轴承因其良好的刚度和承载特性,越来越受到关注。但在微孔节流器的发展过程中,微孔的加工工艺却限制了其推广应用。针对目前常用的三类微孔加工工艺,进行了理论仿真研究,通过建立不同加工工艺轴承仿真模型,运用双向流固耦合仿真方法,对比分析了基于不同加工工艺的微孔节流空气静压轴承的动静态特性。研究结果表明:锥孔类轴承承载性能优于其他两类,但耗气量大且在小间隙时刚度较差;薄壁直孔类轴承承载性能稍逊,但在大间隙下轴承刚度较佳;嵌套类轴承承载性能较差,但在小间隙下轴承刚度较大且耗气量较低。

With the development of ultra-precision machining technology and ground micro-low gravity simulation,the performance requirements for aerostatic bearings are getting higher and higher.Because the structural characteristics of the traditional orifice restrictors cannot fully meet the needs of the actual use,the micro-hole throttling aerostatic bearing restrictors with the same order of magnitude as the air membrane gap has attracted attention more and more,due to its good stiffness and bearing characteristics.However,in the development of micro-hole throttle aerostatic bearing,the processing technology of micro-hole limits its popularization and application.Theoretical simulation research on three prevalent micro-hole machining processes was conducted.By constructing simulation models for each process and employing bidirectional fluid-solid coupling simulation methods,the dynamic and static characteristics of micro-hole restrictor aerostatic bearings produced by these processes were compared and analyzed.The results indicate that tapered hole bearings exhibit superior load-carrying capacity compared to the other two types,albeit with higher air consumption and reduced stiffness at low clearances;thin-walled straight-hole bearings demonstrate marginally lower load-carrying capacity,yet they maintain better stiffness at higher clearances;mosaic bearings,while exhibiting less optimal performance in load-carrying,provide greater stiffness and lower air consumption when the clearance is minimal.