The Research And Simulation Analysis Of Vibration Reduction Mechanism Of Check Valve In Subway Train Brake Pipeline

With the rapid development of engineering technology,hydraulic and pneumatic systems have been applied to every aspect of our life.Under the background of large-scale application,higher requirements are put forward for various types of hydraulic valves,such as improving the grade of noise reduction,energy saving,safety,stability and service life of various valve components on the existing basis.One-way valve is composed of valve spool,valve seat and back-moving spring,the faults which are easy to occur are unable be checked caused by not tightly sealed of valve spool,the service life of the whole valve greatly affected by the vibration wear of the spool,and pollution of working environment caused by greater noise.This paper analyzes the phenomenon of vibration and abnormal noise of one-way valve in train braking system of a Metro Line 2,abnormal vibration and howling of one-way valve are common in complex structure and high frequency system environment,this vibration and howling have great damage to pipeline system and pressure element and affect their service life,and howling is a great disturbance to daily fault detection and judgement of train.Aiming at these problems,the paper analyzes the causes of vibration and howling and gives solutions.In the first chapter of this paper,it summarizes the types of one-way valve and the existing research situation,introduces the effects of material,overall structure and medium on the performance of one-way valve,and summarizes the common causes and treatment of vibration of one-way valve in the system.In the second chapter,the working environment of one-way valve in train braking system of a Metro Line 2 is introduced,and the causes of the vibration of one-way valve in the system are obtained according to its special working environment,the main causes of vibration are: First,material aging of springs,resulting in its own natural frequency and one-way valve operating frequency range overlap which causes high-frequency resonance.Second,the degree of freedom of the spool is increased due to vibration wear of the coordination place of the guide holes of valve core and valve cover,the movement of the spool becomes increasingly irregular and intensifies the vibration.In the third chapter,a series of measures are listed and analyzed,including changing spring stiffness,increasing damping pad,adding damping chamber and damping hole.In terms ofcost-effectiveness ratio,opening damping holes on the valve guide hole wall is most suitable to improve the original one-way valve,on the basis of satisfying the damping effect,the parameters of the components are changed least and the economy is the highest.In addition,damping of the damping hole is increased while the stiffness of the spring is changed,it can better achieve the purpose of vibration and noise reduction.In the fourth chapter,it models a number of one-way valves listed in the third chapter through the use of AMESim software and analyzes simulation results.The simulation results show that increasing spring stiffness,adding damping chamber and damping hole.,and reasonably selecting parameters can greatly reduce the vibration and noise of one-way valve.In the fifth chapter,the one-way valve with damping holes on the guide hole wall of the valve cover is tested and verified,the test results show that the improved one-way valve has good vibration and noise reduction effect.