填砂分段压裂技术在页岩油套变水平井的应用

针对井筒满足承压要求，但由于套管变形不能下入常规压裂工具进行分段压裂的页岩油水平井，通过极限填砂形成缝内砂塞，实现对已压裂层段的有效封隔，采用水平井填砂分段压裂技术进行分段压裂。为了不增加新的设备，研究形成了“尾追填砂”和“吹填缝口”2种填砂模式。长庆油田在华H40平台进行了页岩油套变水平井填砂分段压裂试验，累计填砂压裂8段，各段破裂压力均不一样，封堵效果可靠，施工成功率100%。现场试验结果表明，以“尾追填砂”填砂模式为主、“吹填缝口”填砂模式为辅，可以形成缝内砂塞，有效分隔已压裂层段，实现套变页岩油水平井的分段压裂，解决常规压裂工具无法下入的问题。 

Application of Staged Sand Filling Fracturing Technology in Horizontal Shale Oil Wells with Deformed Casings

In some horizontal shale oil wells, the wellbore can meet the pressure-bearing requirement, but conventional fracturing tools fails to run in them due to casing deformation. To effectively pack the fractured intervals, the technology of staged sand filling fracturing in horizontal wells was adopted and extreme sand filling was used to form sand plugs in the fractures. Two sand filling modes, which included tail sand filling and fracture blowing, were formed to avoid introducing new equipments. In the Platform Hua H40 of the Changqing Oilfield, tests of staged sand filling fracturing were conducted in the horizontal shale oil wells with deformed casings. Eight stages were fractured by sand filling and the fracturing pressure varied at each stage, with good plugging results and a successful treatment operation rate of 100%. The field results demonstrate that sand filling is dominated by tail sand filling and assisted by fracture blowing, and sand plugs in the fractures can be formed to effectively isolate the fractured intervals. Finally, the staged fracturing of horizontal shale oil wells with deformed casings can be achieved, thereby solving the failure of running conventional fracturing tools.