志丹油田麻台区水平井反冲砂工艺研究与应用

Research and Application of Horizontal Well Backflush Sand Technology in Matai Area of Zhidan Oilfield

冲砂作业就是从油管或油套环空中,向井底注入高速流体来冲击砂堵,同时上返循环液体可将砂粒携带出来,进而达到解决油水井砂堵情况。在冲砂过程中,由于冲砂方式、施工人员操作不当、设备出现故障、地层漏失等原因造成冲散的砂子不能及时返出地面,正冲砂方式的冲击力较大,更易冲开砂堵,但由于油套环空横截面积大,导致液体上返速度比较小,携砂能力较弱,进而容易发生卡管事故,而反冲砂管柱下端安装喷头,液流返速快,同时解决了水平段冲砂不彻底的弊病。

The flushing sand is to inject high-speed fluid into the bottom of hole through the tubing or oil casing to flush sand blockage, the upper-back circulation liquid can carry the sand to the ground, so sand blockage problem in oil wells can be solved. In the flushing sand process, scattered sand cannot be promptly lifted to the ground due to improper flushing sand way, improper operation of construction personnel, equipment failure, stratum loss and other causes. The forward flushing sand process is powerful, easy flushes the sand block, but the oil ring annular cross-sectional area is big, so liquid flowback speed is small, sand carrying capacity is low, which easy causes pipe sticking accident. The nozzle is installed at the bottom of recoil sand column, the liquid backflow rate is fast, at the same time, the problem that the flushing sand is incomplete in the horizontal section can be solved.