Research On End Faces Deformation And Performance Of Auxiliary Seal Of Deep Sea Mechanical Seal

Deep-sea thrusters and other underwater operating equipment have many performance indicators,and the rotary shaft seal plays a vital role in the stability and safety of the system.As a form of common rotary seal,mechanical seal has the characteristics of stable sealing performance and long service life.With the change of working depth and speed of underwater operating equipment,the temperature field and end faces deformation of the sealing ring are affected by water pressure,low temperature and other factors,and there is a complex thermo-mechanical coupling effect.In addition,the internal stress and deformation of the auxiliary seal change with the change of working conditions,and the sealing performance is greatly affected by the initial conditions.In this paper,the mechanical seal used in underwater working equipment such as deep-sea thrusters is taken as the research object.The temperature field of the mechanical seal,the deformation law of the end faces,the sealing performance and micro-motion characteristics of the auxiliary seal are studied.It is helpful to explore the deformation control method of mechanical seal faces in marine environment and improve the sealing stability.The main research contents are as follows:(1)The finite element model of the mechanical seal rings is established,and the stress state of the mechanical seal rings is analyzed.The deformation law and the actual contact state of the end faces after stress are studied.(2)The temperature field of mechanical seal ring is studied.According to the working characteristics of underwater working equipment such as deep-sea thrusters,the temperature field and temperature rising law of mechanical seal ring under different depth of water and different navigational speed are studied.The thermal deformation of the end faces and the actual contact state of the end faces after deformation are studied by two analysis methods.(3)The thermal-mechanical coupling deformation of mechanical seal end faces under steady state condition was studied by indirect coupling analysis method.The results were compared with those of mechanical deformation and thermal deformation,and then the deformation law of end faces was summarized based on it.The direct coupling analysis method was used to study the temperature field distribution of mechanical seal rings under transient conditions.(4)Based on the study of temperature field and end faces deformation of mechanical seal rings,several structural optimization schemes are proposed to reduce end faces temperature,thermal deformation and edge stress concentration.(5)Nonlinear finite element analysis was carried out to study the influence of initial compression ratio,material hardness and medium pressure on the sealing performance of auxiliary ring.The micro-motion characteristics of compensation ring and shaft seal ring were also studied,in order to find out the influence of micro-motion on seal rings.