Research On Mechanism Of Reducing Cutting Coal And Drilling Technology In Outburst Coal Seam

The process of construct drilling in Low permeability and soft coal seam is a worldwide technical difficult problem, therefore, research on the drilling deformation mechanism and design a new drilling tool is seen very urgent and necessary.This paper made use of outburst coal mine interrelatd Knowledge and rock crushing mechanism, discussed the coal and rock fragmentation mechanism in outburst coal mine and drilling deformation mechanism, analyzes the factors of drilling deformation, the formation of the drill plastic ring and how to use it, Illustrates the technical feasibility of multi-level adjustable.In the theoretical study on the basis of the above, designed a new drill combination of multi-level adjustable. The drilling using multi-level adjustable technology, several "swallowed" the plastic deformation of drilling; Meanwhile, in addition to the first level adjustable outside, the after drills construct in the former level of crushing circle, Reduces the disturbance of stress and gas dynamic conditions in the front of workface, Eliminates the possibility of nozzle, hole collapse, holding drill, clip drill when drilling.Do the industrial test in the coal mine, collect the parameters of drilling speed, drilling cuttings quantity, final hole depth, and the distribution shape hole of pulverized coal when use the Multi-level adjustable drill to construct bedding drilling. And juxtapose these parameters with PDC drill, the results shows that: the Multi-level adjustable drill's penetration rate is faster than PDC drill's by 52.37%, the Multi-level adjustable drill's drilling cuttings quantity is more than PDC drill's by 40.24%, the Multi-level adjustable drill's final drilling depth is longer than PDC drill's by 40.87%. Therefore, it explains that the Multi-level adjustable drill's effect is better than PDC drill's.