Transient Analysis And Vibration Suppression Of Dry Gas Seal Friction

With the replacement of sealing equipment,the popularity of dry gas seals is getting higher and higher.It is widely used in the petrochemical field.The dry gas seal realizes the non-contact operation which can not be achieved by the traditional mechanical seal.Dry gas seal has the advantages of less leakage,less wear and low running cost,but in the start and stop phase of the dry gas seal,due to insufficient air film pressure generated by the moving ring,the seal ring will produce dry friction unavoidably,causing problems such as friction and wear,vibration and noise,and even material peeling,which seriously shortens the service life of the seal.In this paper,a three-dimensional model was established for the double-face dry gas seal structure widely used in industrial production.The structure meshes were divided by Hypermesh.Instantaneous dynamic analysis of seal ring dry friction was carried out based on Abaqus.The influence of factors such as the groove,groove depth,groove type,material and friction coefficient on the magnitude of frictional vibration were investigated.It was found in the study that under the simulated actual sealing chamber pressure,the vibration amplitude of the friction pair with the groove of the moving ring was obviously larger than that without the groove,which was caused by the difference of the contact pressure distribution;the groove depth had little effect on the friction vibration.The double SiC sealing ring pairing was better than the graphiteSiC pairing;when the friction coefficient was reduced,the friction vibration generated by the system would be significantly reduced;The friction pair of the T-shaped groove moving ring showed better friction properties than the classical spiral groove under the same working condition.In order to achieve the purpose of vibration suppression,the shape of tiling,vertical stripes and diamond grooved bionic textures were designed.The vibration characteristics of different texture surfaces were simulated by the flat-slider model.The vibration of the diamond texture was the most stable.For the secondary optimization of the diamond texture size,it was found that the larger the diamondshaped region,the smaller the root mean square value of the friction vibration,which was beneficial to the system operation.Once again,the optimization of the diamond angle showed that the 70° groove damping effect was the best,and it was continuously set in different positions of the static ring for calculation.The friction pair set in the inner ring of the static ring(corresponding to the moving ring dam area)showed good vibration damping effect.The finite element transient analysis of the dry friction movement in the dry-gas seal start-stop phase was carried out for the first time.The friction and vibration characteristics of the sealing system under different structures and parameters were discussed.The designed pangolin bionic fabrics achieved the purpose of vibration suppression,and the simulation results lay a solid foundation for future experiments and engineering applications.