| Hydraulic cone valves are important basic components in hydraulic transmission and control due to their good sealing performance,simple structure,and no "dead zone" when opening.However,in engineering applications,the problems of reduced control accuracy,noise pollution,and even hydraulic valve function failure caused by steady-state hydraulic power and vibration seriously limit the application of cone valves.With the development of hydraulic transmission technology towards high pressure,high precision,and large flow,engineering applications have put forward higher requirements for the performance of cone valves.Therefore,studying the steady-state hydraulic power and vibration characteristics of hydraulic cone valves is of great significance.This article uses a combination of theoretical analysis,numerical simulation,and experimental analysis to study the steady-state hydraulic power and vibration characteristics of cone valves.There is a close correlation between steady-state hydraulic force and vibration of cone valves.In previous studies on the vibration characteristics of cone valves,the research results have shown that the source of cone valve core vibration is the imbalance of force on the cone valve core,and the important reason for this imbalance is the steadystate hydraulic force received by the valve core during its movement.Therefore,this article first studied the steady-state hydraulic force of the cone valve.Based on the momentum theorem and the analysis of the steady-state hydraulic force mechanism,the formula for calculating the steady-state hydraulic force of the cone valve was modified.In response to the key factors that affect the steady-state hydraulic force in the formula,a cone valve structure scheme that can compensate for the steady-state hydraulic force of the cone valve was proposed,that is,adding an arc structure on the cone surface of the cone valve to compensate for the steady-state hydraulic force,Then,by using the method of flow field simulation,the influence of arc structure parameters on steady-state hydrodynamic force was explored,and the optimal arc structure parameters were obtained.The results were verified through experiments and AMEsim software.The results showed that:(1)the corrected steady-state hydrodynamic force formula was correct;(2)The conical valve core with an arc structure can achieve steady-state hydraulic compensation.Under the optimal arc size,the steady-state hydraulic compensation effect of the conical valve core increases with the increase of the opening degree.Under the working conditions of a pressure difference of 1.7 MPa and an opening degree of 2.02 mm,the steady-state hydraulic compensation can be 25 N.Taking the designed steady state hydrodynamic compensation poppet valve and the original poppet valve as the research object,based on the dynamic simulation model of the poppet valve and the experimental platform,the axial and radial vibration characteristics of the poppet valve cores with two structures under various parameter changes were studied by using the Control variates through the combination of theory and experiment,and the relationship between the vibration characteristics and the steady state hydrodynamic force was explored by comparing the vibration characteristics of the poppet valve cores with two structures,conclusion:(1)The influence of steady-state hydraulic force and spring force on vibration characteristics is similar.When the force of both increases,the vibration balance position of the experimental cone valve will decrease,and the valve core opening will decrease;(2)The cone valve designed in this article can compensate for steady-state hydraulic force.Due to its steady-state hydraulic force compensation effect,under the same inlet pressure,outlet pressure,and spring pre compression,the axial vibration balance position of the cone valve core is larger than that of the unmodified cone valve core;(3)Under small opening,the steady-state hydrodynamic compensation structure can reduce the axial and radial vibration amplitude;(4)As the experimental inlet and outlet pressures,as well as the pre compression amount of the spring change,the vibration characteristics of the steady-state hydraulic compensation cone valve and the original cone valve generally have consistency.That is,as the inlet pressure increases,the axial and radial amplitudes of the two valve core structures increase,and the axial vibration balance position increases,but the growth rate gradually decreases.The gradual decrease in growth rate is caused by the increase in steady-state hydraulic growth rate.As the outlet pressure increases,The axial and radial amplitudes of the valve core first decrease and then increase,and the balance position value of the axial vibration of the valve core decreases and the deceleration gradually accelerates.As the pre compression of the spring continues to increase,the balance position value of the axial vibration of the valve core decreases,the axial amplitude decreases,and the radial amplitude decreases.This article designs a cone valve core structure that can compensate for steady-state hydraulic force.This structure can be applied in practical engineering to achieve the effect of steady-state hydraulic force compensation,and can also reduce the vibration amplitude of the valve core under small opening degrees;The influence of inlet and outlet pressure and spring pre compression on the vibration characteristics of two types of cone shaped cone valves was studied,providing a theoretical basis for eliminating the vibration of cone shaped cone valves.The relationship between steady-state hydraulic force and vibration characteristics was also explored,providing a reference basis for the joint optimization of steady-state hydraulic force and vibration characteristics of cone shaped cone valves. |
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