Through the theoretical analysis on the coal breaking mechanism of drill bit and the factors influencing the change of drill pipe speed in the drilling process,the corresponding change relationship between the drilling rate and the drill pipe speed was put forward,and the experimental analysis was carried out by using the drilling device,the loading device and the self-developed multi-parameter testing device of drilling. The feasibility of measuring the coal stress by using the drill pipe speed method was verified,and the change laws of the drill pipe speed under different drilling rates were studied. The results showed that when the parameters of drill bit,drill pipe and coal-rock mass and the idle speed of drill pipe before the drill-ing were fixed,the drill pipe speed presented a functional relationship of negative exponent with the drilling rate approximate-ly,the smaller the drilling rate,the larger the drill pipe speed,and on the contrary,the smaller the drill pipe speed. The study on the influence of the drilling rate on the drill pipe speed can reduce the error in the prediction of the dynamic disas-ters such as rock burst by using the speed index,so as to achieve the efficient early warning.%通过对钻孔过程中的钻头破煤机理及影响钻杆转速变化的因素进行理论分析,提出了钻进速度与钻杆转速的对应变化关系,并利用钻进装置、加载装置及自主研制的钻孔多参量测试装置进行试验分析,验证了利用钻杆转速法测定煤体应力大小的可行性,同时对不同钻进速度下钻杆转速的变化规律进行研究.结果表明:在钻头、钻杆、煤岩体参数及钻孔前钻杆空转转速一定时,钻杆转速与钻进速度大致呈现负指数的函数关系,钻进速度越小,钻杆转速越大,反之,钻杆转速越小.研究钻进速度对钻杆转速的影响,可以减少利用转速指标对冲击地压等动力灾害的预测误差,实现高效预警.
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