脉动水力压裂钻孔密封参数的测定及分析  

Borehole sealed parameter measurement and analysis of pulsating hydraulic fracturing

作　　者：倪冠华[1] 林柏泉[1] 翟成[1] 李贤忠[1] 李全贵[1] 

机构地区：[1]中国矿业大学安全工程学院煤炭资源与安全开采国家重点实验室,江苏徐州221116

出　　处：《中国矿业大学学报》2013年第2期177-182,共6页Journal of China University of Mining & Technology

基　　金：国家自然科学基金重点项目(51074161);国家重点基础研究发展计划(973)项目(2011CB201205);煤炭资源与安全开采国家重点实验室自主研究课题(SKLCRSM08X03)

摘　　要：为了改善脉动水力压裂钻孔密封性能,选择膨胀水泥冻复合材料(简称PD复合材料)作为密封材料,采用具有典型代表性的管径为95mm和108mm的内壁粗糙的无缝钢管作为模拟钻孔,在不同封孔长度条件下,对压裂密封参数进行实验测定分析.结合Lagrange插值法,计算在所需压力条件下,钻孔密封合理长度.结果表明:PD复合材料承压能力与封孔长度成正比,与钻孔直径成反比.当钻孔直径较小时,钻孔密封段内裂隙扩展的困难程度随封孔长度的增加而增加;反之,随封孔长度的增加而减小.脉动频率越高,对钻孔密封的承压性能要求越高,且高频的脉动压力更有利于脉动压裂过程中钻孔密封段内裂隙的产生与扩展.当脉动水力压力为16MPa时,脉动水力压裂过程中合理的封孔长度为13m.In order to improve the drilling sealed performance of pulsating hydraulic fracturing, selecting expansive cement freeze composite materials （PD composite material） as sealing mate- rial, using the diameters of 95 mm and 108 mm rough inner wall seamless steel pipe as simula- tion drills, the sealed parameters were experimentally determined and analyzed under the conditions of different sealed length. Combined with Lagrange Interpolation, the reasonable sealed length was calculated under the condition of required pressure. The results show that the bearing capacity of PD material is proportional to the sealed length and inversely proportional to the sealed diameter. The difficulty of crack propagation in the sealed section increases with the sealed length when the drilled diameter is smaller. Otherwise, it decreases with the sealed length. The higher ripple frequency is, the higher performance of the sealed horehole requires. And the higher ripple frequency is more conducive to fracturing process and expansion of cracks in sealed section of the borehole. When the pulsating hydraulic pressure is 16 MPa, the reasonable sealed length is 13 m.

关 键 词：PD复合材料 脉动水力压裂 密封参数 实验测定 

分 类 号：TD712[矿业工程—矿井通风与安全]