机械密封浮动环处O形密封圈动态刚度和阻尼的测量

利用INSTRON高频疲劳试验机对O形辅助密封圈进行松弛试验,获得气体和水润滑2种状态下O形辅助密封圈载荷随时间的变化曲线,通过数据处理获得其轴向动态刚度和阻尼,根据经验公式进一步确定其角向刚度和阻尼。分析O形辅助密封圈在气体和水润滑下动态刚度和阻尼随着加载频率、位移、转速的变化规律。结果表明:在气体和水润滑下,在一定范围内辅助密封圈的动态刚度和阻尼值随加载频率的升高而增大;在水润滑状态下,随着加载位移量的增大,辅助密封圈的动态刚度和阻尼值逐渐变小;在气体和水润滑下,都存在一转速临界值,在临界值之前,随转速的增加,轴向动态刚度增大,轴向动态阻尼减小;在临界值之后,轴向动态刚度和阻尼值不再变化,稳定在某一值。

Measurement of O-ring Dynamic Stiffness and Damping Used in a Flexibly Mounted Rotor Mechanical Seal

To obtain the load curves for the assistant O-ring under two states of gas lubrication and water lubrication,relaxation test of the O-ring was taken by using INSTRON high frequency Fatigue Stress Testing Machine.The axial dynamic stiffness and damping coefficients of the O-ring were gained by data processing,and its angular values confirmed further according to the empirical formula.The variation rules of O-ring dynamic stiffness and damping along with the loaded frequency,displacement and rotate speed under gas lubrication and water lubrication were analyzed.The results show that the dynamic stiffness and damping coefficients of the O-ring increase along with rising of loaded frequency in a certain range under gas and water lubrication;and decrease gradually along with increasing of loaded displacement under water lubrication state.There is a critical speed value existed all under gas and water lubrication.At less than speed critical value,the dynamic stiffness increases along with increasing of rotate speed,but the axial dynamic damping decreases.At more than the speed critical value,the axial dynamic stiffness and damping get the stable values.