Numerical Simulation And Application Of Bedding Gas Drainage Drilling Parameters In Soft Coal Seam

In this paper, it analyzes the influence factors on soft coal seam drilling based on the status quo of soft coal seam gas drainage drilling in a mine of DongRong, the influences of spray holes, partings, top floor and coal gun on the deep drilling are listed. Fluent software is used to carry out the numerical simulation about wind velocity flow field in drilling wind slagging and particle playground. The simulation results show that, with the increasing depth of the hole, the airflow speed of the drilling inner hole exhibits a non-linear increasing trend. With increasing depth of the hole punch, airflow speed exhibits a linear decreasing trend. The speed of the cinder particles changes with the drilling length, part of the cinder particles are blown out of the orifice, which take up 11% of the total amount of slag, another part of cinder particles are remained in the drilling holes, which take up 89% of the total amount of slag.In addition, the experimental study is carried out on mining smooth drilling pipe and high-strength groove drilling pipe. After analysis and comparison, we find that, when the ordinary smooth drilling pipe are drilling coal seam,if it is soft coal, because the cinder can not be discharged in time, so the sticking phenomenon can easily occur, resulting in a shallower drilling, which can not meet the actual demand. Groove groove drilling pipe is added more groove on the ordinary smooth drilling pipe, which effectively solve the sticking phenomenon after the geological conditions and coal quality changes when drilling.