可捞式桥塞在水平井分段隔离压裂上的应用

Application of fishable bridge plug in staged isolation fracturing in horizontal well

针对国内各油田主要采用填砂+液体胶塞、限流法分段或合压裂工艺进行水平井分段压裂存在的问题,开展了机械桥塞隔离井筒试验。桥塞胶筒主要由内胶筒、端部接头、骨架心子、外胶筒组成。水平井机械隔离分段压裂管柱分为3类,分别是桥塞传送坐封、桥塞打捞和压裂管柱。坐封桥塞管柱结构为丝堵(单流阀)+液压释放工具+油管,桥塞打捞管柱结构为JAY型回收工具+液压扶正器+油管,压裂管柱结构为喷砂器+油管+封隔器+水力锚+油管+井口。2口井压裂施工数据和桥塞打捞作业中可看出桥塞没有漏失和移位现象,说明桥塞起到了良好的封堵隔离作用。

For the problems existing in the staged fracturing in horizontal well mainly by using sand-filling plus liquid gel slug, limited entry staged or commingled fracturing technology in domestic oilfields, the test of isolating wellbore by mechanical bridge plug is carried out. The packing element of the bridge plug is mainly composed of inner packing element, end connector, bone mandrel and outer packing element. The staged fracturing string has three categories: bridge plug convey setting, bridge plug fishing and fracturing string. The structure of setting bridge plug string is plug (check valve), hydraulic releasing tool and tubing. The structure of bridge plug fishing string is Jay type recycling tool, hydraulic centralizer and tubing, and the structure of fracturing string is sand blower, tubing, packer, hydraulic anchor, tubing and wellhead. It can be seen from the fracturing data and bridge plug fishing in two wells that the bridge plug has no leakage and shift, showing that the bridge plug has good isolation.