PTFE rectangular seal ring has the advantages of good chemical resistance and high section stability,which can effectively solve the sealing problem of corrosive media.However,in actual use,the size design of PTFE rectangular ring and its matching groove lacks reference.In view of the above problems,according to the shape and stress characteristics of the end sealing structure of high pressure vessels,a two-dimensional axisymmetric model of PTFE rectangular seal ring was established in Ansys Workbench,and a bilinear isotropic hardening model was used to characterize the mechanical properties of PTFE.The sealing structure of PTFE rectangular seal ring for high pressure vessels end face was analyzed and designed,and the influence of compression ratio,geometric parameters of PTFE rectangular seal ring and groove structure parameters on the physical quantities related to the sealing performance of pressure vessel end face was discussed.The results show that the compression ratio,height and width of the rectangular ring,and the gap between the rectangular ring and the groove sidewall have a greater impact on the sealing performance,while the inner diameter has a smaller impact on the sealing performance.Therefore,when designing,priority should be given to the parameters such as groove depth,cross-sectional size of the rectangular ring,and assembly position between the rectangular ring and the groove.The dimensions of PTFE rectangular seal ring and matching groove were determined,and the sealing performance of the designed sealing structure was verified using finite element simulation at room temperature and 30 MPa high pressure,confirming the rationality of the design.