工作介质属性对水基推力静压轴承刚度的影响

Influence of working medium properties on stiffness of water-based thrust hydrostatic bearing

针对水基静压轴承存在刚度较低的问题,研究了水基推力静压轴承工作介质的属性与轴承刚度之间的关系。首先,采用梯形丝杆、测力传感器、位移传感器和节流器等元件构建了一种水基静压轴承刚度评估装置,静压轴承的刚度通过施加到支承台上的实测载荷和轴承位移来计算;其次,分别采用自来水和纯水作为工作介质,考察了工作介质属性对水基静压轴承刚度的影响;最后,在改变水的成分和水的温度的情况下,对轴承的刚度进行了试验,并在试验中通过测量轴承的载荷和刚度,对轴承的性能进行了评价。研究结果表明:(1)随着轴承位移的不断增加,两种情况下的轴承刚度均呈现先升后降的趋势;(2)使用纯水作为工作介质时,在水温20℃~50℃范围内,轴承最大刚度随水温升高而增加;(3)使用自来水作为工作介质时,在水温20℃~50℃范围内,轴承最大刚度呈现先升后降的趋势;该试验结果可为改善水基静压轴承的刚度提供参考。

Aiming at the problem of low stiffness of water-based hydrostatic bearing,the relationship between the properties of working medium and bearing stiffness of water-based hydrostatic bearing was studied.Firstly,a stiffness evaluation device for water-based hydrostatic bearings was constructed by using trapezoidal lead screw,force sensor,displacement sensor and throttle.The stiffness of hydrostatic bearing could be calculated by the measured load and bearing displacement applied to the bearing platform.Secondly,tap water and pure water were respectively used as working medium,and the influence of working medium attributes on the stiffness of water-based hydrostatic bearing was investigated.Finally,in the case of changing the composition of the water and the temperature of the water of the bearing,the stiffness of the bearing was tested.In the test,the performance of the bearing was evaluated by measuring the load and stiffness of the bearing.The experimental results show that:(1)with the increasing of bearing displacement,the bearing stiffness in both cases shows a trend of rising first and then falling;(2)when pure water is used as working medium,the maximum bearing stiffness increases with the increase of water temperature in the range of 20℃to 50℃;(3)when tap water is used as working medium,the maximum bearing stiffness increases first and then decreases in the range of 20℃to 50℃.The test results provide feasible suggestions for improving the stiffness of water-based hydrostatic bearings.