旋转式唇型圈停车密封开启全过程密封特性研究

Research on Sealing Characteristics of Rotary Lip Type Parking Seal in the Whole Opening Process

为探究旋转式密封圈脱开全过程的密封性能参数变化,借助非线性有限元软件ANSYS,建立三维的“超弹性体”的两参数Mooney-Rivlin橡胶模型、弹簧和“刚体”的静止轴模型,研究传统唇型密封圈和2种新型唇形密封圈(G形与S形)在脱开过程中接触压力、接触宽度、摩擦力的变化规律,分析入口压力、过盈量、弹簧力、橡胶密度对脱开转速的影响。结果表明:3种旋转式密封圈的接触压力、接触宽度均随转速增加而减少且减少的速率相同,摩擦力随转速的增加先增大再减少;3种旋转式密封圈的最大接触压力均发生在唇口靠近空气侧,空气侧与介质侧的接触宽度之比为2∶1,从唇口到空气侧的0.6 mm内,接触压力均趋近于最高值;入口压力对脱开转速影响最大,橡胶密度对脱开转速的影响也较大,而过盈量和弹簧力的影响较小;G形和S形唇形密封结构的脱开转速比传统密封结构低40%左右,证明了环形弹簧的离心力能够加速唇口的脱开。采用压力监控的实验精确地测定开启转速,实验结果与数值分析结果相差较小,证明了数值分析的准确性。

In order to explore the change of sealing performance parameters during the whole opening process of rotary sealing rings,a three-dimensional Mooney-Rivlin rubber model of“super elastic body”and a static shaft model of spring and“rigid body”were established by means of nonlinear finite element software ANSYS.The changes of contact pressure,contact width and friction force of traditional lip seal ring and two new lip seal rings(G-type and S-type structure)in the process of separation were analyzed.The influence of inlet pressure,interference,spring force and rubber density on the disengagement speed was analyzed.The results show that the contact pressure and contact width of the three rotary sealing decrease with the increase of rotating speed,and the decreasing rate is the same.The friction force increases first and then decreases with the increase of rotating speed.The maximum contact pressure of the three rotary sealing rings occurs near the air side of the lip.The ratio of the contact width between the air side and the medium side is 2∶1,and the contact pressure tends to the highest value within 0.6 mm from the lip to the air side.The inlet pressure has the greatest influence on the disengagement speed,the rubber density also has a great influence on the disengagement speed,while the interference and spring force have little influence.The disengagement speed of G-type and S-type sealing structure is about 40%lower than that of traditional sealing structure,which proves that the centrifugal force of ring spring can accelerate the disengagement of lip.The opening speed was accurately measured by the pressure monitoring experiment.The difference between the experimental results and the numerical analysis results is small,which proves the accuracy of the numerical analysis.