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.