Estimation And Experimental Research On The Screening Efficiency Of Hydraulic Linear Vibrating Screen

As the core equipment for material screening,vibrating screen has been applied in various fields.Most of the existing vibrating screens are inertial vibrating screens,driven by an eccentric motor,and the vibration frequency and amplitude are not convenient for real-time adjustment during operation,and are only suitable for working under specific vibration parameters.In this paper,the screening performance of the hydraulic linear vibrating screen is studied.The vibrating screen is controlled by a hydraulic directional valve to control the periodic reciprocating movement of the piston rod of the asymmetric hydraulic cylinder,and then the hydraulic cylinder drives the screen box to vibrate.Real-time adjustment of vibration related parameters under working conditions to achieve the best performance of the system.Firstly,introduce the working principle of the hydraulic linear vibrating screen,combining with the theoretical foundations of vibration mechanics,fluid mechanics,hydraulic transmission and control,establishes a mathematical model of the system,derives the mathematical model of the movement of a single particle material on the vibrating screen,and obtains it by solving The sliding and throwing conditions of the material on the screen.Secondly,the modal analysis and harmonic response analysis of the screen frame of the hydraulic linear vibrating screen were carried out through ANSYS Workbench,and the results showed that the structure of the vibrating screen frame was good.Secondly,use the EDEM software to simulate the screening process of coal particles on the hydraulic linear vibrating screen,focusing on the relationship between the screening efficiency,the law of material movement on the screen and the vibration parameters(vibration frequency,amplitude,inclination angle of the screen)and the shape of the screen mesh.The simulation results show that the smaller the amplitude,the vibration frequency,and the inclination angle of the screen surface,the greater the screening efficiency of the vibrating screen,and the screening efficiency is the highest when the screen hole shape is rectangular under the same opening rate.Finally,build an experimental platform for the hydraulic linear vibrating screen,and design an orthogonal experiment with a certain screen mesh shape to study the influence of vibration parameters on the screening efficiency.The amplitude of the hydraulic linear vibrating screen is completely determined by the pump displacement.Through a large number of experiments,it is found that the influence on the screening efficiency from strong to weak is the pump displacement,the inclination angle of the screen surface,and the vibration frequency.The vibration frequency is 12 Hz,the inclination angle is 4.5°,and the displacement is 28 m L/r is the combination of the best sub-efficiency.At the same time,the pressure curves of the left and right chambers of the hydraulic cylinder and the stress curve of the system during the screening process of the hydraulic linear vibrating screen are collected.Through the analysis of the experimental curve,it is known that there is an impact phenomenon during the working process of the vibrating screen,which reduces the occurrence of the blocking of the screen mesh and is beneficial to the improvement of the screening efficiency.In this paper,a dynamic analysis of the structure of the vibrating screen frame is carried out,combined with theoretical analysis,simulation and experiment to study the influence of the vibration parameters on the screening efficiency when the shape of the screen mesh is fixed,which is the theoretical research and application promotion of the hydraulic linear vibrating screen Provided for reference.