煤矿瓦斯抽采顺层钻孔偏斜规律试验研究

Experimental study on the deviation rule of gas extraction boreholes along seam in coal mines

针对煤矿瓦斯抽采顺层钻孔偏斜问题,通过现场试验,利用测斜仪器对钻孔轨迹基本参数进行测量,采用均角全距法对钻孔偏移量进行计算,研究了顺层钻孔偏斜的一般规律,结合现场施工情况,分析了钻孔偏斜原因。结果表明:顺层钻孔轨迹普遍呈现上偏的趋势;以20 m为一个考察区间,钻孔倾角最大变化率位于>40~60 m区间内;技术因素、地质因素和人为因素是导致钻孔偏斜的主要因素。研究结果为预防钻孔偏斜以及进一步研究顺层钻孔保直防斜技术提供科学依据。

Aiming at the problem of the deviation of gas extraction boreholes along seam in coal mines,the basic parameters of the drilling trajectory were measured by inclinometer through field test.With the method of the equal angle and total distance,the drilling borehole offset was calculated and the general rule of the deviation of borehole along seam was studied.Combined with the field constructions,the reasons led to the deviation of the borehole were analyzed.The results showed that the trajectory of boreholes along seam generally was of an upward trend;with an inspection interval of 20 m in drilling direction,the maximum change rate of borehole dip angle was in the range of>40~60 m.Technical factors,geological factors and artificial construction factors were the main factors led to borehole deviation.The conclusions provided a scientific basis for preventing borehole deviation and for further researching of straightening anti-slanting technology in drilling along seam.