爆炸压裂下围压对井壁破碎效果的影响  

The Effects of Ambient Pressure on Wellbore Crushing Effect Under Explosive Fracturing

作　　者：徐鹏[1] 程远方[1] 刘丹[2] 彭钧亮[2] 

机构地区：[1]中国石油大学(华东)石油工程学院,山东东营257061 [2]中国石油西南油气田分公司采气工程研究院,四川广汉618300

出　　处：《石油钻探技术》2009年第6期22-25,共4页Petroleum Drilling Techniques

基　　金：国家高技术研究发展计划("863"计划)项目"低渗低丰度油气田井内动载压裂开采新技术"(编号:2007AA06Z208)部分研究内容

摘　　要：针对爆炸压裂容易在井壁周围造成粉碎区、形成致密压实带的问题,进行了室内爆炸压裂模拟试验。试验结果表明,向试样施加围压后,爆炸压裂效果明显不同于常压下的爆炸压裂效果。试样在常压下进行爆炸压裂后,炮眼直径变大,炮眼周围区域粉碎效果明显;向试样施加一定围压后再进行爆炸压裂试验,粉碎区域消失,试样表面宏观裂缝数量增加,产生的裂缝较短,造缝效果明显好于常压下的爆炸压裂效果。以此为基础,重点考虑了围压对爆炸压裂效果的影响,分析了爆炸压裂时井筒周围岩石的受力情况,并根据分析结果推导了既能保证井壁稳定又能使井眼周围地层形成裂缝的边界条件,并通过室内试验对其准确性进行了验证。The explosive fracturing was tested in house in order to solve problem of formation compact caused by smash area around the wellbore resulting from explosive fracturing. The results show that the explosion result of cement sample under confining pressure is different with that under ambient pressure. Under ambient pressure, the blast hole of cement sample became bigger and the smash area was obvious around blast hole; while under confining pressure, the smash area disappeared and the number of fractures increased and the length of the fractures were better than those under ambient pressures. The effect of confining pressure on explosion results was investigated, and the stress of rock around wellbore during explosion fracturing was analyzed. The boundary conditions which can maintain wellbore stability and create factures was derived and verified using in-house tests.

关 键 词：低渗透油气藏 岩石力学 爆炸压裂 封闭压力 实验室试验 

分 类 号：TE357.14[石油与天然气工程—油气田开发工程]