| In recent years,with the improvement of China's coal consumption level,the advancement of coal mining technology,and the improvement of domestic and foreign mining equipment manufacturing levels,the mining of thin and extremely thin coal seams in China has received increasing attention from the state and coal enterprises.However,due to the slow development of mechanized mining technology for extremely thin coal seam,a large number of abandoned mining problems exist in all mining areas in China.To improve the recovery rate of coal resources and meet the requirements of gas fire control,it is urgent to realize large-scale mining for extremely thin coal seam.Therefore,the research on key technology of sliding saw mechanized mining methods of the extremely thin coal seam is very necessary for the safe and stable development of each mining area and the improvement of mining efficiency of the extremely thin coal seam.In this paper,the thin coal seam working face of Xuyong coal mine in Sichuan province is taken as the research object,and the research is carried out through theoretical analysis,numerical analysis,and numerical simulation.(1)A mechanized mining method for ultra-thin coal seam sliding saw was designed.By analyzing the occurrence characteristics of the thin coal seam,as well as the three-machine supporting structure and coal falling characteristics of the current slotting machine,the mining height can be determined by theory and value Adjustable,bottom-sliding sliding saw shearer,high-strength narrow fuselage shifting and pushing support(bracket),coordinated with the "three machines" supporting self-moving scraper conveyor,the relevant technical parameters are adopted as a whole The anti-skid technology of the sliding and stepping type integrated moving frame realizes the unmanned or small-number coal mining working face of the working face.(2)Design an optimized working face layout with 110 working method and roadway method,to realize the up-mining wind protection roadway at the working face stage.According to the independent ventilation system of coal and gas outburst formation Y,each mining face forms an economic disaster control mode of effective coupling of mining and gas outburst control engineering from the essential safety guarantee of the mine.(3)In the mining direction of extremely thin coal seam,the plastic zone of overburden strata is deformed and represents the shape of an arch.The area with the largest vertical displacement is in the middle of stope.The plastic zone of overlying strata in the inclined direction is relatively higher in the middle of the stope.and the maximum displacement is in the middle the roof.The both ends majorly shows shear bond destruction,and the middle of overlying strata majorly shows tensile destruction.the load of the support body beside the roadway increases as the slant angle of the coal seam decreases and the mining height index increases,it drops rapidly at first but the decrease rate drops as time passes.Roof cutting and flexible formwork roadway protection can effectively prevent gas from flowing into the roadway,therefore ensure the satisfaction of standard requirements for mine ventilation system and the stability of surrounding rock,and ultimately improve the mining safety and coal recovery rate.(4)A sliding saw mechanized mining method of the extremely thin coal seam is implemented in the engineering practice of xuyong coal mine.The application of some schemes on the four coal mining faces in the S12 mining area can achieve an efficiency of 23 million yuan.The economic and social benefits will be better after the implementation of all the schemes.This paper puts forward a kind of extremely thin coal seam sliding saw type mechanized mining method applies to all nearly horizontal and inclined thin coal seam mechanized mining or part of a thin layer of metal continuous mechanized mining,special gas,and fire control can satisfy the protection for extremely thin coal bed mining technology needs. |
PDF Full Text Request