State Key Laboratory Cultivation Base for Gas Geology and Gas Control, Henan Polytechnic University, Jiaozuo
College of Safety Science and Engineering, Henan Polytechnic University, Jiaozuo
State Collaborative Innovation Center of Coal Work Safety and Clean-Efficiency Utilization, Henan Polytechnic University, Jiaozuo

针对水力冲孔和机械刀臂扩孔增透易塌孔、刀臂收合不畅等问题,提出水力驱动柔性刀具扩孔增透技术思路。理论分析不同压力条件水动力马达扭矩和转速变化规律,建立柔性刀具转动惯量和动能计算模型,确定影响柔性刀具破煤的关键因素。基于自行研制的水力驱动柔性刀具破煤系统,选取赵固二矿煤样,开展扭矩、转速测量实验和不同因素对破煤效率影响实验,确定摩擦损失系数k和b分别为0.67和0.447;研究射流压力、破碎时间和接触长度对柔性刀具破碎质量、平均破碎深度和柔性刀具动能的影响规律,揭示提高破煤效率的关键因素。结果表明:柔性刀具破煤可以分为冲击破坏和磨削破坏2个阶段,其中冲击破坏决定破碎坑体积,而磨削破坏可以为破碎坑体积扩大做前期准备。射流压力对破煤效率影响显著,25MPa相比10MPa破碎质量提高11倍,平均破碎深度提高4倍,柔性刀具动能增加3倍。受实际工况限制,适当延长破碎时间对提升破煤效率更有效,接触长度对破碎质量和平均破碎深度的影响规律为先增加后减小并趋于稳定。提出的水力驱动柔性刀具破煤在水力冲孔和机械刀臂扩孔基础上改进,为低透煤层扩孔增透提供了新方法和新思路。

To solve the problems of hole collapse and poor engagement of cutter arm in hydraulic punc- hing and mechanical cutter arm reaming and permeability enhancement, hydraulic driven flexible tool expansion and permeability enhancement technology are proposed. Theoretical analysis of torque and speed variation of hydrodynamic motor under different pressure conditions, the calculation model of rota- tional inertia of flexible tool and kinetic energy is established and the key factors affecting the coal brea-king of flexible tool are determined. Based on the self-developed hydraulic driven flexible tool coal brea- king system,the coal samples from Zhaogu No.2 Mine are selected to carry out the torque and speed measurement experiments and experiment of influence of different factors on coal breaking efficiency, and determine the friction loss coefficient k and b respectively 0.67 and 0.447. The influence law of jet pressure, breaking time and contact length on the effect of breaking mass, average breaking depth and kinetic energy of flexible tool are studied, revealing the key factors for improving coal breaking efficien- cy. The results have shown that: The coal breaking of flexible tools can be divided into two stages: im- pact damage and grinding damage. The impact damage determines the volume of breaking pit,and the grinding damage can prepare for the expansion of breaking pit volume. The jet pressure has a significant effect on the coal breaking efficiency,25 MPa has 11 times higher breaking mass, 4 times higher average breaking depth and 3 times higher kinetic energy of flexible tool than 10 MPa. Due to the limitation of actual conditions, it is more effective to prolong the breaking time properly to improve the efficiency of coal breaking. The influence of contact length on breaking mass and average breaking depth increases in- itially,then decreases and tends to be stable. The hydraulic driven flexible tool coal breaking technology is improved on the basis of hydraulic punching,which provides a new method and insight for reaming and permeability enhancement of low permeability coal seams.

国家自然科学基金项目(52174170,52274193,52374193);中国博士后基金项目(2023M741846);河南省科技攻关项目(242102321172);河南理工大学创新型科研团队资助项目(T2024-1)