Research On Vibration Property Of Screw-In Cartridge Proportional Flow Valve

Because screw-in cartridge valves has its compact structure, zero leakage, easy installation and maintenance and other advantages, so in the small flow field it has become one of the main valves. With the development of hydraulic technology towards to high pressure, large flow and high speed, the performance requirements of hydraulic valves are also increasing. Vibration of hydraulic valve spool can cause the spool positioning unreliable, output flow instability, even lead to many problems, such as the failure of machinery parts and large noise. Therefore, the research on vibration of hydraulic valve plays a guiding role to improve the performance of the hydraulic valve.Whether in domestic or abroad, No matter the structure of valve spool is cone valve or the cylindrical slide valve, the results about research on vibration property of hydraulic valve indicates that the sources of spool vibration are pointing to the imbalanced force of the valve spool, the main factors causing the imbalance is the steady-state flow force and transient-state flow force during in the process of spool movement.Based on the theory of vibration, Aimed to the screw-in cartridge proportional flow valves of fixed orifice structure in this paper, from the perspective of flow field distribution, using FLUENT analysis the flow field distribution of spool valve in 5.2MPa,10.4MPa under the steady-state and transient-state. Simulation analysis the change in pressure and velocity on surface at different valve opening and valve spool moving speed under two kinds of pressure drop, the results show that there is a non-linear relationship between the pressure, the velocity distribution and pressure drop, opening and valve spool moving speed.Meanwhile, Research focuses on the analysis of the steady-state flow force and transient-state flow force at different opening and makes the comparison between the steady-state flow force and transient-state flow force. The comparing results revealed that there is no obviously difference between the steady-state flow force and transient-state flow force. Therefore, the main source of the vibration of the valve spool cannot be verify by the simulations. In order to further study the main factors that cause the valve spool vibration, the flow force on the valve is analyzed in theory, theoretical analysis results and the fluid dynamic simulation data are basically consistent, established the dynamic equation of the spool through the theoretical force analysis and simulation is conducted by using SIMULINK software, simulated the vibration under the effect of both steady-state flow force and transient-state flow force and working alone, the results that transient flow force is the main factor to cause the valve spool vibration are obvious.