Study on the Effective Influence Radius of Advance Discharge Drilling by Difference Method of Drilling Cuttings Amount

In order to improve the efficiency of testing the effective influence radius of advance discharge drilling, on the basis of the test method of drilling cuttings amount, the construction measurement drilling was changed to the direct construction discharge drilling, that means, two discharge boreholes were constructed at the same location in the coal mine. By using the cuttings difference between two discharge boreholes in tests, the effective influence radius of advance discharge drilling was determined, and the procedure of reaming was omitted, the test efficiency of influencing radius was improved. According to difference method of drilling cuttings amount, the effective influence radius of advance discharge drilling in the M5^# coal seam at coal mine site was test. Considering the complexity of downhole conditions, 5 measuring points were arranged in the test area, it was required that there should be no less than 2 measuring points along the coal seam tendency and no less than 3 measuring points along the coal seam inclination. It was concluded that the effective influence radius of advance discharge drilling in the M5^# coal seam is from 0.56 m to 0.61 m, the accuracy of the result was verified by introducing the critical index of drilling cuttings amount. From the perspective of safety, the effective influence radius of advance discharge drilling in the M5^# coal seam was finally determined to be 0.50 m.