Research On The New Type Of Steam Seal With No Gap At The End Face Of Steam Turbine Shaft

As one of the three core equipment of thermal power plant,the working state of steam turbine can directly affect the economic benefits of the whole thermal power enterprise.Therefore,improving its relative internal efficiency can effectively achieve the purpose of energy conservation and emission reduction.However,there are many defects in the existing steam turbine shaft seal system,for example,it is easy to cause wear on the rotor,large steam leakage,etc.,these defects also cause the relative efficiency of the steam turbine unit to reduce,economic deterioration and so on.Under this background,a new type of shaft end face non gap contact steam seal is proposed in some literature,which can effectively reduce the steam leakage,even achieve the effect of zero steam leakage.In view of this new type of gland,this paper introduces its working principle,and makes a more detailed design on its structure.Through theoretical analysis and finite element numerical simulation,it analyzes and calculates the operation stability of the new type of gland itself and the rotor after the installation of the new type of gland.It also makes a model for the reliability of the new type of gland and the modal influence of the new type of gland on the rotor The feasibility of the new type of steam seal is verified by analysis.The simulation results show that the temperature distribution and stress distribution of the seal pair after rubbing are uniform and reasonable,which will not cause the bending deformation of the turbine shaft,and verify the reliability of the new type of steam seal.After adding a graphite ring with a certain axial end pressure at the disk of the rotor shaft end,the damping frequency and the corresponding critical speed of the rotor change compared with the original rotor in the allowable range In the enclosure,it shows that the use of the new type of steam seal will not affect the operation stability of the steam turbine.At the same time,it also provides the theoretical basis for the operation characteristics,reliability analysis and subsequent practical verification of the steam seal.