Kinematic Analysis Of Transmission Mechanism And Research On Dynamic Characteristic Of Movable Sieve Body Of Downhole Mechanical Movable Sieve Jigger

The development of the technology and equipment at discharging the gangue of downhole coal mine is a scientific developing direction of coal industry in our country. The downhole mechanical movable sieve jigger because of its simple structure and convenient maintenance is a more ideal equipment on discharging the gangue downhole. Its overall design basic retains the core technology of the mechanical movable sieve jigger. In the paper, based on expatiating the theoretical foundation of coal jigging and the mechanism of jigging stratification, the whole structure and working principle of the downhole mechanical movable sieve jigger are discussed. The kinematics of the transmission mechanism is analyzed and the dynamic characteristic of the critical component-the movable sieve body is studied.The movement rule of the transmission mechanism of downhole mechanical movable sieve jigger directly affects the efficiency of discharging the gangue. In the paper, according to the working principle of the transmission mechanism, the design variables and function parameters are determined. A parameterized model of the transmission mechanism is established and simulated by using assembly method on the ADAMS platform. Then the effects of each design variable whose value ranges are determined appropriately with the help of numerical analysis method in MATLAB software on the function parameters are analyzed. The design requirements are satisfied after the structural parameters of the transmission mechanism are adjusted.The movable sieve body as the main working part of the downhole mechanical movable sieve jigger driven by the transmission mechanism swings around the support shaft, forms the screen surface vibration. In the paper, according to the engineering drawings and structure parameters of the movable sieve body of LTD18/3.6movable sieve jigger, the entity model of the movable sieve body of the downhole mechanical movable sieve jigger is designed and established in3D software UG and then imported to ANSYS Workbench after simplified and processed. The inherent frequency of the movable sieve body is obtained through the modal analysis and it is verified that the resonance do not happen when the movable sieve body works. In order to verify the strength property of the movable sieve body, the structure analysis and the harmonic response analysis are processed and the equivalent stress nephogram and the displacement nephogram of the movable sieve body in the worst conditions are obtained. The result shows that the maximum stress concentrates in the contact with the swing arm frame on the back sieve plate and the maximum displacement appears on the intermediate bracket of the swing arm frame. In the end, according to the analysis results above the structure of the movable sieve body is improved. The stress concentration phenomenon disappeares and the maximum stress and displacement are reduced. The expected efforts are achieved.