The Status Performance And Leakage Rate Finite Element Analysis For The C-rings In Dry Gas Seal

Dry gas seal is a new-style non-contact seal.It is used in rotating machinery such as compressors,pumps,gas turbines,expanders and so on.Dry gas seal could be used in the harsh condition,such as high temperature and high pressure.Dry gas seal has more small abrasion,less leakage,lower power consumption compared with traditional mechanical seal.Dry gas seal mainly consists of two parts: gas film seal between dynamic and statics rings,seal of auxiliary seal ring.Auxiliary seal ring not only plays a role in sealing but also affects following nature of compensation ring.It will influence the film thickness,film rigidity,film speed and so on,these change will affect the leakage of dry gas seal,it makes seal will lose efficacy.So auxiliary seal rings is very important in the whole dry gas seal system and reasonable installation and used of compensation is also very important for the whole dry gas seal system.The finite element analysis of the status performance and leakage rate of C-rings.In this paper,the PTFE material parameters of the main material of C-rings was determined by uniaxial tensile test.Finite element method and MSC Marc soft ware were used to build the three-dimensional model of C-rings.Three nonlinear problems and their solving methods are described of C-rings.The influence compression ratio and medium pressure on the C-rings max Von Mises stress,the contact stress were analyzed and the spring plays role in the C-rings seal.The most easily damaged parts of C-rings were determined.Last,the C-rings leakage rate was analyzed by Roth.A leakage theory.Analysis results show that the material model of PTFE is described by two order Mooney-Rivlin model.The cross-sectional area of the tensile specimen decreases with increase of tensile length,and reduce speed becomes slower and slower.The contact stress and max Von Mises of C-rings the whole is enlarged with the medium pressure and the compression ratio.The most vulnerable parts of C-rings appears it contact with springs gap and the maximum Von Mises stress deformation in here.The existence of the spring has a great influence on the stress intensile and distribution of C-rings.Although the spring increase Von Mises stress of C-rings,it also increases contact stress.And it make the sealing performance of C-rings becomes better.The leakage rate of C-rings decreases with the increases of compression ratio,and it increase of sealing surface roughness,and it increase with the medium pressure increases.So,appropriately increasing the compression ratio and surface roughness is more helpful for sealing.The reference is provided for the design and selection of C-rings for dry gas seal.