| Hydraulic support is a very important equipment in fully mechanized mining face,and its dynamic reliability has an important impact on coal mine safety production.The hydraulic support test-bed is the equipment to test the factory hydraulic supports.In recent years,with the application of hydraulic supports with a mining height of more than 8 meters,the development of a larger tonnage hydraulic support test-bed is an urgent problem to be solved.Combined with the research status of Hydraulic Support Test-bed at home and abroad,based on the project of "dynamic analysis and reliability optimization design of 50000 KN Hydraulic Support Test-bed",this paper studies the strength and fatigue life of Hydraulic Support Test-bed under eccentric load conditions based on virtual prototype technology,rigid flexible coupling multi-body dynamics,fatigue cumulative damage and grey correlation theory,as follows:Firstly,according to the eccentric load condition of the hydraulic support,the stress analysis of the movable beam system of the test bench is carried out,and it is determined that under the internal and external loading mode,the stress condition of the two pins near the cushion block side is worse.The three-dimensional solid models of the hydraulic support and its test-bed are built through Creo,the flexible parts of the movable beam,bolt and column are built through ANSYS,and the rigid flexible coupling system of the internal and external loading hydraulic support test-bed is built in ADAMS.The influence of the internal and external loading mode on the structural strength of the test-bed is analyzed.The simulation results verify that the stress condition of the two pins near the cushion block is worse,and the strength of the movable beam is insufficient under the external loading mode,At the same time,it is found that the external loading mode has a greater test on the strength of the test-bed.Then,aiming at the problem of insufficient strength of the movable beam,the influence of the thickness,length,position and other factors of the stiffener plate of the movable beam on its weight and maximum stress is analyzed by orthogonal test.The entropy weight method is used to calculate the maximum stress and the weight coefficient of the stiffened plate of the movable beam,and the best optimization combination is selected according to the grey correlation theory.After optimization,the maximum stress of the movable beam is reduced by 97.54 MPa and the weight is reduced by 510.25 kg.Based on the theory of orthogonal test and grey correlation,an idea is provided for the optimal design of hydraulic support test-bed.Finally,the fatigue life of the optimized test-bed is analyzed.Through nsoft fatigue life calculation,the minimum fatigue life,fatigue damage and fatigue life nephogram of movable beams,pins and columns in eccentric load strength test and durability test are obtained respectively.The research shows that in the eccentric load strength test,the fatigue life of the movable beam is low,and the damage occurs at the contact position between the T-channel steel of the movable beam and the cushion block.By replacing the T-channel steel,the service life of the movable beam of the test-bed can be effectively improved.This paper has 75 figures,20 tables and 67 references. |
PDF Full Text Request