井下定向钻进用小直径通缆水力振荡器的研制

Development of small diameter hydraulic agitator with cable for directional drilling in underground coal mine

针对煤矿井下定向钻进过程中由于托压效应引起的钻进摩阻大、钻进效率低、钻孔深度受限等问题,提出通过钻柱振动减阻的技术思路。采用理论分析和数值模拟进行激振力、激振频率等关键技术参数的设计,研制Φ89 mm小直径通缆水力振荡器。在室内测试碟簧和圆柱弹簧两种辅助复位原件结构的振荡器性能,并在淮南张集煤矿井下进行实钻试验。结果表明:碟簧式水力振荡器在300 L/min流量时,最大压降1.9 MPa、激振力8.11 kN、频率13 Hz,适合安装在近钻头位置辅助减阻;圆柱弹簧式水力振荡器频率在300 L/min流量时,模拟测试150 m通缆定向管柱最大变形量2.86 mm,最大复位力7.98 kN,频率11 Hz,适合安装在钻柱中间主要减阻;在张集矿井下-600m疏水巷10号孔定向钻进产生明显托压时使用圆柱弹簧式水力振荡器,使平均钻压降低33%,钻效提高126%,显著降低钻进摩阻,提高定向钻进效率。研制的Φ89 mm小直径通缆水力振荡器为煤矿水平定向钻进中托压问题提供一种新的解决方法。

Aiming at the problems of large drilling pressure,low drilling efficiency and limited hole depth caused by the backing effect of drill string during deep hole directional drilling in underground coal mine,the technical idea of using hydraulic agitator was proposed.TheΦ89 mm small diameter hydriculic agitator was designed based on valve principle,the exciting force,excitation frequency were identified,and the cabled sub was developed.The performance parameters of hydraulic agitator with disc spring and cylindrical spring were tested.The results show that when the flow rate of 300 L/min the disc spring hydraulic agitator has the maximum pressure drop of 1.9 MPa,the exciting force of 8.11 kN,the frequency of 13 Hz,can be installed near the bit for friction reduction partly.The maximum deformation of drill string is 2.86 mm,the reset force is 7.98 kN,the frequency is 11 Hz with cylindrical spring with 150 m cabled drill string under the flow rate of 300 L/min.The agitator was used when the baking pressure was obviously generated during drilling No.10 hole in-600 m drainage lane,in Zhangji coal mine of Huainan.The average drilling pressure was reduced by 33%and the average drilling efficiency was increased by 126%.The friction of drilling was significantly reduced and the efficiency of directional drilling was improved.The developed small-diameterΦ89 mm cabled hydraulic agitator provides a solution for the backing pressure problem in horizontal directional drilling in coal mines.