Research On Wear Failure Model Of Electro-Hydraulic Servo/Proportional Valve

As the core component of electro-hydraulic servo/proportional control system,electro-hydraulic servo/proportional valve has been widely used in engineering technology.In order to improve the work performance of the electrohydraulic servo/proportional valve and reduce the dependence on foreign servo/proportional valve products,it is necessary to conduct in-depth research on the key factors affecting the valve performance and life.Electro-hydraulic servo/proportional valves generally use slide valve components as their power stage,which act as hydraulic booster in the hydraulic system.After the slide valve is working for a period of time,the valve sleeve and the valve core will have different degrees of wear,which are manifested by the increase of the radial clearance of the valve sleeve and the deformation of the throttle edge.These failure modes have a huge impact on the flow field characteristics inside the valve body,causing different changes in the flow area and flow velocity of the spool valve port.At the same time,the flow coefficient of the slide valve is also one of the important parameters reflecting the flow characteristics of the valve port.It is not only related to the opening degree and the shape of the throttle side,but also related to the radial gap between the valve sleeve and the valve core.Therefore,the main research content of this paper is to simulate the erosion wear simulation and flow field characteristics of slide valves with different throttling forms.This paper takes the typical slide valve structure as the research object,proposed a similar model of the internal wear of the slide valve.Combined with the actual situation,the wear condition of the slide valve and the throttle edge,a three-dimensional slide valve model is established by using SolidWorks,and using the finite element analysis software ANSYS/Fluent to simulate the erosion wear of the throttle,which is used to judge the life of the slide valve.Then,the flow field simulation analysis is carried out on the slide valve model with different forms of throttling edge.The relationship between the over-flow area of the valve port and the opening degree is given for the slide valve port under different throttle sides,and the approximate value of the over-flow area is calculated,based on the principle of minimum cross-section as the valve port flow area.The static characteristics of each model under different opening degrees are analyzed,including valve port flow characteristics,velocity characteristics,internal leakage characteristics,and the theoretical and simulation analysis of the flow coefficient changes is also carried out.At last,the hydraulic test bench is used to test the internal leakage characteristics of the slide valve,based on the theoretical calculation and modeling simulation.Taking the valve core as the test object,and three different type of throttle as the working edge,obtain the internal leakage characteristic curve of the slide valve.These analysis and research results can be used to judge the performance of the slide valve,and play a guiding role in the optimal design of the slide valve structure.