Analysis on production reliability of dragline with the variation of average coal seam thickness

The paper adopts the method of Numeral Statistic to estimate the range of the thickness based on a great deal of the datum of bore holes in-situ which can reduce the effect of the coal thickness as regionalized variable, takes the throughput of dragline as a variable, puts forward the concept of the dragline's production reliability on the condition of the change of coal seam thickness, establishes the model of machine-nature reliability of dragline-coal seam thickness, and defines the formula of calculating the value of reliability, which gives a valid method of researching the reliability of dragline-coal seam thickness.