Study on the Sealing Performance Analysis and Design Method of Graphite Gasket

In order to systematically study the sealing performance analysis and design method of graphite gasket, test, theoretical calculation and numerical simulation are carried out in this paper simultaneously. The graphite gasket mechanical deformation analysis model and three-dimensional bolt-flange-gasket sealing analysis model are established. Characteristic of compression-resilience curve of gasket, coordinated deformation mechanism of bolt-flange-gasket, contact stress variation law under typical working conditions are studied. The study results show that, the compression-resilience process of gasket represents nonlinear deformation which can be divided into four typical deformation stages. Numerical simulation result of compression-resilience fits well with test result curve which verifies the correctness and effectiveness of the numerical analysis method. The sealing analysis result of bolt-flange-gasket shows that, the gasket stress and sealing pressure under preloading and working condition all meet the design requirements. In transient condition, the increased axial load caused by medium pressure and temperature gradient is mainly supported by the outer metal ring, and sufficient radial size of the outer metal ring is critical to ensure the sealing stability of the graphite ring.