Research On The Key Technologies Of Cartridge Proportional Relief Valve

With the continuous improvement of electro-hydraulic control elements,the combination of the proportional control technology and the two-way cartridge technology has made great progress.Compared with the traditional tube valve,plate valve and stacking valve,cartridge valve is more in line with the development trend of modularization,configuration,open-designed and integration.Now,the two-way cartridge valve is mainly used in high pressure and large flow conditions,while in the medium flow conditions,the traditional plate valve and stacking valve are mainly used.Therefore,it is of great significance to study the two-way cartridge valve in the medium flow field to promote its development.Cartridge proportional relief valve aiming at the medium flow field was explored from the overall scheme,the damping network and structural parameters systematically through multidisciplinary optimization design method.The test prototype of cartridge proportional relief valve was developed and the feasibility and correctness of the proposed multidisciplinary optimization design method were verified by experiments and provided reference for the design of the same type hydraulic valve.The research contents of this thesis are organized as following:(1)A new structure of the cartridge proportional relief valve was proposed aiming at the disadvantages of large volume and unsatisfactory flow field distribution caused by the vertical installation of the main stage and the pilot stage of the existing cartridge proportional relief valve on the market.Pilot damping network and valve port structures of proportional relief valve were designed according to the new structure scheme.(2)Proportional solenoid and proportional amplifier were chosen according to the control characteristics of the proportional relief valve.Test platform which is used to test steady-state performances of proportional solenoid was designed and actual parameters of the selected proportional solenoid were tested.The steady-state flow forces and flow field distribution of the pilot valve core with different cone angles of pilot valve core and pilot valve seat conical surface were simulated by CFD software.The formula for calculating the clearance between the pilot valve and pilot valve was derived on the premise of ensures the stability of the pilot stage.(3)The steady-state flow forces of the main valve core under different structural forms and different cone angles were simulated and calculated.The minimum wall thickness of the main valve sleeve under different loads was calculated by finite element simulation software ANSYS and the passage of main valve port and the diameter of main valve core were designed accordingly.Fit clearance and structure of valve core were designed in consideration of the internal leakage caused by the fit clearance between the valve core and the valve sleeve and the hydraulic clamping force on the valve core.(4)A valve sleeve inner cone angle measuring platform which aims to solve the difficulty of the measuring of the inner cone angle was put forward to control the influence of processing error of inner cone angle on the performance of the relief valve.A hydraulic component testing system with computer aided test system and test program was set up to ensure the feasibility and reliability of relief valve performance test.The influence of different damping network on performances of relief valve and the optimal dynamic damping aperture under different damping networks were explored through combination of AMESim software simulation and experimental test.The dynamic and static performance of the relief valve with different pressure levels were tested under the optimal structural parameters.The test results showed that all the performance of the designed relief valve met the design objectives.The proportional relief valve designed in this thesis was compared with excellent similar products at home and abroad by experiment under the same experimental conditions and the results showed that the former has advantages in terms of step response time,stability,and pressure overshoot.