Study On Interacted Vibration Characteristics Of High Parameterized Spiral Groove Mechanical Sealing System

In the rotating equipment of petrochemical industry at home and abroad,bellows mechanical seal has been widely used because of its good sealing performance,high reliability,small leakage and long service life.However,the working parameters of bellows mechanical seals are also developing towards high parameters and complex working conditions.Especially in the case of high temperature,high pressure,extreme cold and heat conditions in Xinjiang,the friction pairs of bellows mechanical seals will appear coupling vibration,which will cause leakage and affect the sealing performance.Although there are some studies on the coupling analysis of mechanical seal system at home and abroad,they all focus on the thermal fluid-solid multi-field coupling analysis,and do not consider the rigid-flexible multi-body of bellows mechanical seal system,so there are still many problems.Firstly,bellows mechanical seal is a rigid flexible multi-body structure,which includes bellows,moving rings,static rings,fluid film,rotating shaft and other components.Under the comprehensive influence of heat-fluid-solid multi-field coupling,including the thermodynamic interaction between sealing rings and the Thermal-Fluid-solid interaction between fluid film and solid sealing rings at the interface of friction pairs,there is a very complex non-linear relationship between components.Previous studies mainly focused on qualitative analysis,and the establishment of specific theoretical models was not perfect enough.At the same time,there are many literatures on the dynamics of rigid-flexible multi-body coupling system,but most of them do dynamic modeling and analysis for simple mechanical system,while the numerical modeling and vibration characteristics of rigid-flexible multi-body coupling and Thermo-Fluid-Solid multi-field coupling complex system such as bellows mechanical seal system are very few at home and abroad,so the mechanical seal system of bellows is seldom studied.The research on multi-body multi-field coupled vibration and failure analysis has important theoretical and scientific significance.Based on this background,this paper presents a method to study the coupled vibration characteristics of welded metal bellows mechanical seal system,establishes a mathematical model of the coupled vibration of the dynamic and static rings of welded metal bellows and end friction pairs,and solves the vibration equation of the multi-degree-of-freedom system by programming with Python tool.The motion composition of the coupled vibration of the friction pairs of mechanical seals and its relationship with the structure of the system are analyzed.The influence of different working parameters on the coupling vibration of welded metal bellows mechanical seals is obtained,which provides a useful reference for the design of bellows mechanical seals and a way of thinking and direction for controlling the coupling vibration.