Research On Mechanism And Characteristic Of Single Labiate Type Sealing Ring Of High Pressure Quick Actuating Structure

Based on the needs of scientific research and deep-sea equipment testing,the project proposed the development of a test platform capable of simulating the deep-sea pressure environment,of which the key equipment is a horizontal high-pressure cylinder.The paper established a nonlinear finite element analysis method of rubber sealing structure based on the Rezone technology to research the quick actuating sealing structure,and preliminary revealed the characteristics and mechanism of the single labiate type sealing structure,and analyzed the influence of various factors on its comprehensive performance.The main works of thesis are listed as follows:(1)The constant temperature tensile test of nitrile rubber at different temperatures was completed,and the constitutive model of rubber material was established.By comparing the advantages and disadvantages of various constitutive models of rubber materials,the suitable constitutive model was determined.Meanwhile,the trend of mechanical properties of nitrile rubber was analysed when the operating temperature changed.(2)Aiming at the characteristics of the single labiate type seal structure,a nonlinear finite element analysis method based on Rezone technology is established.The main parameters and the reasonable contact analysis algorithm of the high-pressure quick actuating seal structure were determined.The use of Rezone technology has been solved the problem of grid distortion and convergence caused by the large deformation of the seal.A finite element analysis program including the loop calculation of re-mesh has written,and the failure criterion for the single labiate type seal structure was determined.(3)The numerical simulation analysis of the single labiate type seal structure under different pressures was completed,the results of which preliminarily revealed the self-tightening mechanism of seal structure.According to the deformation of the single labiate type seal ring and the distribution of the contact pressure on the seal surface,the relationship between the maximum contact pressure and the medium pressurethe was established,which showed the effect of medium pressure change on the contact pressure.The results showed that the maximum contact pressure on the sealing surface was always greater than the medium pressure in the design pressure range of the horizontal pressure cylinder,and there is a positive correlation between the two.(4)The effects of radial compression,axial compression and seal cross-sectional area on the performance of the single labiate type seals were studied,the results of which helped to optimize the key parameters of the high pressure quick actuating sealing structure.Considering the sealing performance of the structure,it was determined that the mounting resistance of the sealing ring and the opening and closing resistance of the cylinder cover,the reasonable assembly relationship between the sealing ring and the sealing groove.Based on the same amount of radial compression and axial compression,the increase of the cross-sectional area of the sealing ring could maintain the original sealing performance as well as effectively reduce the installation resistance of the sealing ring and the opening and closing resistance of the cylinder cover.It could slow the extrusion of the sealing ring and reduce its shear stress,which helped to improve the number of repeated use of the single labiate type seal.