The Study On The Reliability Of Coal Mining Face By Fully-mechanized Longwall Along Strike Of Pitched Seam

In the recent years, with the continues increasing exploitation of deep and the inclination larger coal seam, and the development of modern fully-mechanized coal mining technology, the Coal mines of mining pitched seam (35°~ 55°) in China are increasing, annual yield is enlarging, and benefit is improving.Our research more on the reliability of the system of fully-mechanized mining faces. However, the research results confined to the gently inclined seam, but the research focus of fully-mechanized longwall along strike of pitched seam is devoted to equipment selection, the study on reliability is very lack in China. Although, fully-mechanized mining makes great progress, the pitched seam mining conditions is very complexity, there are lots of unreliable factors in mining process. It mainly includes three aspects of human, equipment and environment. Firstly, human subsystem unreliable factors contains human behavior, operating machines and manpower organization and management, etc.. Secondly, machine subsystem unreliable factors are that unstable powered support may lead to reliability of support system is lack, specially the serious problem is inverted, slip, extrusion or"bite"powered support each other and a shearer and a AFC(Armored Face Conveyor) slip. Finally, environment subsystem unreliable factors are that roof is very difficult management; floor downslide results in powered support unstable and the collapsing accident of support, coal and gangue are self-slide and strongly impulsive force, the rock is easily to hurt workers, impact support and hack up equipment. In order to improve the reliability and safety of coal mining, the coal mine of pitched seam should be strengthened the reliability study of coal mining face of full-mechanized longwall along strike of pitched seam.This paper demonstrate the unreliable factors of fully mechanized longwall mining face of the subsystems and fault mechanism under the steeply dipping seam special mining conditions from the three aspects of person - machine - the environment. and compared the unreliable factors of subsystem with the gently inclined coal seam mining face, it establish the Pedersen model and the factor of environment model, analyses the dominant factor with AHP(Analytical Hierarchy Process) and calculates the fuzzy reliability and validity with the method of fuzzy comprehensive; it analyze the structure reliability of the main fully-mechanized mining equipment, support system, shearer and scraper conveyor which easy unbalance ,using the method of structure reliability, and establish the support system limit state equations of structural stability and the model of structural reliability in order to estimate the index of structure reliability, the adjustment of structural parameters can reduce the trend of support inverted and slip and improve structural reliability of support; establish the reliability calculation method of the fully-mechanized longwall along strike pitched seam mining face system of the human-machine-environment; according the principle of fault tree, analysis the fault factors of system step by step for the coal mining face form the human-machine-environment, analysis the improvement methods of the optimal reliability of system. An engineering example of the fully-mechanized mining face of 6134 has been verified in Liushuidong Coal Mine of HuaYing Mountain, using the paper's method, which result of calculation is approximate same as the actual measurement. The research and advice of this paper has conference significance to improve system reliability of Coal mines whose main coal seam is pitched seam.