Study On Vibration Characteristics Of High Frequency Vibrating Screen Based On Finite Element Method

The vibrating screen,as a kind of material classification and screening equipment with small amplitude and high screening efficiency,is widely used in heavy industry such as metallurgy industry,construction,petroleum industry,coal industry and chemical industry,it has a large share in light industry such as tobacco.High-frequency vibrating screen is not only impacted by material,but also affected by large alternating loads for a long time in the production process.Thus,it often leads to the destruction of the structure and the short service life of working.The type GPS(12)254.0 high frequency vibration screen produced by Qinhuangdao Tobacco Machinery Company also has a series of problems in the process of tobacco screening,such as low screening efficiency,short working life and high start-up noise.This topic takes this type of high frequency vibration screen as the research object,and carries out the research and optimizates the vibration parameters of this vibration screen.In this paper,the motion differential equation of high-frequency vibrating screen is established by using the principle of virtual work and Lagrange equation,and its natural frequency is obtained.The shell element,mass element,link element and six types of beam element with different cross-section shapes in ANSYS are used to simulate the structures of high-frequency vibrating screen,and APDL command flow is compiled to establish the finite element model of the high-frequency vibrating screen.Found on the situation,finding the natural vibration characteristics of high-frequency vibrating screen structure by finite element method,and the experimental mode of the vibrating screen is obtained by combining the manual hammering method.The natural frequencies extracted by the finite element method are compared with those obtained by the finite element method.At the same time,the response analysis of the structure is carried out,and the displacement and stress responses of the vibrating screen are obtained and checked.Through the above analysis,it is found that the natural frequency and dynamic stress of the vibrating screen do not meet the requirements of safe production.After repeated demonstration,the web and floor thickness of the beam of the high-frequency vibrating screen body are increased,and the dynamic analysis of the improved structure is carried out.The results show that the modal frequencies of each order are far away from its working frequency,and the dynamic stress decreases from 81.184 MPa to 46.279 MPa,which basically meets the design requirements.Finally,combined with the previous research results,he static strength analysis of high frequency vibrating screen was carried out.On this basis,the fatigue life prediction of the key position of the high frequency vibration screen is carried out by using ANSYS fatigue module.Based on the finite element method,the vibration parameters of high-frequency vibrating screen are optimized and analyzed in this paper,which provides a strong reference for the optimization of the future modification of this type of vibrating screen,and also has a certain reference value for the design and manufacture of Chinese vibrating screen in the future.