Simulation And Experimental Research On Pressure Shock Of Valve-controlled Cylinder System With Heavy Load And Large Flow

The hydraulic system of the full hydraulic double-side shearing shear has the characteristics of high speed,heavy load and large flow.In the process of plate production,if a large load is encountered,the shearing process will stop,resulting in a large pressure shock in the hydraulic cylinder,the pressure shock will make the piston unstable,which not only affects the production quality of the steel,but also causes the hydraulic components are damaged.Therefore,it is significant to reveal the causes of the impact of pressure shocks.The effective volume elastic modulus of hydraulic oil is an important attribute of hydraulic oil,and the effective volume elastic modulus is affected by the gas content in the oil.According to AMEsim simulation,the maximum error between the effective volume elastic modulus value and the theoretical value solved by the compression method is about 9.98%,and the curve of the effective volume elastic modulus changes with the gas content is obtained.The equivalent dynamic spring stiffness of the hydraulic cylinder reveals the ability of the hydraulic cylinder to resist deformation.The equivalent dynamic spring stiffness of the hydraulic cylinder must be considered.By dividing the cavity on both sides of the hydraulic cylinder piston,the cavity on both sides is equivalent to two springs are connected in series to find the equivalent dynamic spring stiffness of the hydraulic cylinder,and the minimum dynamic spring stiffness is 800 MPa and the position of the piston is 0.172 m at this time.The time of the pressure shock occurred is 0.0047 s that is calculated by the cosine series,and the accuracy of the time was verified by AMEsim simulation software.The theoretically derived pressure shock is compared with the data collected on site,and the maximum error is 11.12%,which indicates the correctness of the obtained pressure shock.The study of hydraulic system pressure shock reveals the internal factors that affect the pressure shock,including the gas content in the oil,the effective volume elastic modulus and the equivalent dynamic spring stiffness of the hydraulic cylinder.