Theoretical study on the drilling cuttings considering coal seam angle and borehole angle

In order to predict and prevent coal and gas outburst in deep mining, a new theoretical calculation method of drilling cuttings quantity considering coal seam angle and drilling angle was established, and the influence of coal seam angle and drilling angle on drilling cuttings was analyzed.Compared and verified the theoretical calculation value of cuttings with the measured drilling cuttings amount in wind alley Ji₁₅-21030 of Pingdingshan No.8 Coal Mine.It is concluded that when the coal seam angle is constant, the drilling cuttings decreases exponentially with the increase of borehole angle, and the decreasing ratio shows a "V" shape, the average error between theoretical value and measured value of original drilling cuttings is 5.5%, and the average error between theoretical value and measured value of new drilling cuttings amount is accurate to 3.9% when the coal seam angle and drilling angle is considered.