松软煤层瓦斯抽采钻孔冲洗液应用研究

Application of Flushing Fluid in Gas Drainage Drilling of Soft Coal Seam

为了提高松软煤层瓦斯抽采钻孔深度,提出了冲洗液钻进工艺,针对煤层瓦斯抽采钻孔自身特点,配制了粉基冲洗液和液基冲洗液,并进行了钻具性能影响测试和现场应用试验。结果表明:该冲洗液有助于提高孔底马达输出扭矩和输出转速;具有自动降解功能,成孔后不会堵塞瓦斯抽采通道,不会影响瓦斯抽采;能够显著提高冲洗介质的黏度,从而有效提高冲洗介质排渣能力,有助于提高松软煤层瓦斯抽采钻孔深度。

To improve the depth of gas extraction borehole in soft coal seam,the drilling technology of flushing fluid is proposed.According to the characteristics of coal seam gas extraction borehole,the powder-based flushing fluid and liquid-based flushing fluid were prepared,which passes through the impact test of drilling tool performance and field application test.The results show that the solution can improve the output torque and speed of the motor at the bottom of the hole;with the function of automatic degradation,the hole will not block the gas extraction channel,will not affect the gas extraction;it can significantly improve the viscosity of the flushing medium,so as to effectively improve the slag discharge capacity of the flushing medium,and help to improve the depth of gas extraction borehole in the soft coal seam.