Design And Research Of Filling Machine In The Goaf Of Open Bit End Slope Coal Mine

Our country has a huge amount of coal resources at the open bit end slope coal mine.According to incomplete statistics,the amount of domestic large-scale open-pit coal mines has exceeded 5 billion tons.Due to the limitations of domestic mining technology and mine equipment,most open-pit mines have only retained coal at the end.At present,many coal mines have started mining in the open bit end slope coal mine,but the filling mining technology has not been widely implemented.The traditional open-pit backfill mining technology is complicated in filling technology,it is difficult to support the roof of the goaf,and it is impossible to effectively recover the end-side compressed coal resources.Therefore,this thesis proposes a new type of filling machine used in the open bit end slope coal mine filling and mining.In order to meet the goal of the goaf filling operation,a more detailed study has been carried out on the mechanical structure of the filling machine,the hydraulic system and the pneumatic filling.Based on the open pit coal filling mining technology,the overall structure design of the filling machine is determined,and a pneumatic filling technology of filling machine in the goaf of open bit end slope coal mine is proposed.The structure of the filling machine including crawler walking mechanism,pipeline manipulator and baffle device is designed and finite element analysis,and the filling and pushing operation of the filling machine is simulated by EDEM software to provide a basis for the calculation of the hydraulic system.The hydraulic system of the filling machine is designed and analyzed,and its key hydraulic component—load-sensitive pump is analyzed and a mathematical model is established.Based on AMEsim modeling software,the typical hydraulic branch system of the filling machine is simulated.The analysis results show that the load-sensitive proportional multi-way valve system can control multiple actuators to move at the same time.The upper and lower cylinders can move synchronously in proportion and will not change with load changes.The hydraulic system can meet the working requirements of the filling machine.The filling piping system of the filling machine is designed,which has good applicability.The simulation analysis of the pneumatic conveying of gangue particles in the filling pipeline shows that as the velocity and particle size of the flow field increase,the energy obtained by the particles from the flow field increases,and the particles move in a suspended state.The pressure change of the flow field in the filling pipeline is studied,and the results show that the static pressure of the flow field increases with the increase of the particle size and the flow field velocity.In the actual conveying process,the conveying capacity of the pneumatic conveying system can be improved by selecting a reasonable particle size and increasing the gas velocity.Based on the design and research of the filling machine for the coal goaf of the open-pit mine,the prototype was trial-produced,and the performance of the prototype was tested.The results show that the whole machine runs smoothly and all parts can work normally.The upper and lower cylinders can move in proportion to the speed.A test bed for pneumatic conveying of the filling machine was built to test the pneumatic conveying effect of the gangue of the filling machine.The test results show that the pressure drop changes with the change of the particle size and the velocity of the flow field.The effect of the velocity of the flow field on the pressure drop is particularly obvious,indicating the correctness of the simulation results.The thesis has 66 figures,7 tables,and 113 references.