Abstract:Aimed at the valve used in oil product pipeline,the analysis model of the sealing structure of the stem was established,the relationship between the sealing effect and the sealing medium pressure was studied for three kinds of different sealing structures.A new valve stem seal performance comprehensive evaluation method was proposed.The results show that the sealing performance of the valve stem can be evaluated from three aspects,the maximum contact stress between the sealing contact surface,the peak Mises stress in the actual working condition of the seal and the deformation of the seal under the pressure of sealing medium.The sealing performance of the sealing ring with Vshaped groove is the strongest among the three kinds of sealing structures,and the slip ringtype combination ring with rectangular groove posses the worst sealing performance.Under the same conditions,the peak value of Mises stress of the sealing ring with Vshaped groove is the largest,and the peak value of Mises stress of the slip ringtype combination ring with rectangular groove is the smallest.The combination of the combined ring with the rectangular groove can effectively solve the problem that the seal ring is squeezed into the groove.