抽油机井可环空测试井筒防喷技术

Blowout prevention technology for annulus testable well in rod-pumped wells

为了解决抽油机井检泵作业过程中井液喷出污染环境的问题,满足生产时不动管柱过环空测试的需求,开展了可环空测试井筒防喷技术研究。通过研制Y445封隔器、阀芯式井下开关等核心工具,与抽油泵、捅杆形成防喷工艺管柱。生产时,阀芯式井下开关开启,最小内通径Ø36 mm,为测试仪器起下提供了中心通道;检泵作业时,下放泵抽管柱时关闭阀芯式井下开关以实现井筒防喷。利用有限元模拟分析了0~25 MPa不同套压下工艺管柱的密封性能和锚定性能,最高防喷压力28.4 MPa,防上顶力不小于422 kN。室内实验结果表明,工艺管柱在25 MPa套压下安全可靠。该技术在大庆油田现场试验了5口井,二次检泵作业2口井,施工全程井口无溢流,过环空产出剖面测试仪器通过顺畅、无卡阻,实现了抽油机井不压井检泵作业和不动管柱过环空测试。

During pump inspection,the fluid from oil well often blows out and pollutes the environment,to solve this problem and at the same time to meet the needs that the immovable string passing through annulus for testing during production,the research on the blowout prevention technology of the well that can be tested in the annulus was carried out.The core tools such as Y445 packer and spool type downhole switch were developed,and these core tools together with oil well pump and poke rod formed a set of blowout prevention pipe string.During production,the spool type downhole switch will be in an open state,with a minimum inner diameter ofØ36 mm,which provides a central channel for the testing instrument to be lifted and lowered.While during pump inspection,the lowered pump string will close the spool type downhole switch to prevent well blowout.The sealing and anchoring performance of the process pipe string under different casing pressures from 0 to 25 MPa was analyzed by finite element simulation.The simulated results show that the blowout prevention pressure is 28.4 MPa,and the anti-jacking force is greater than 422 kN.The laboratory test results show that the process string is safe and reliable under the casing pressure of 25 MPa.The technology has been tested on 5 wells in Daqing Oilfield,including 2 wells for secondary pump inspection.There is no overflow at the wellhead during the whole testing process,and the testing instrument passing through annulus producing profile passes smoothly and without jamming.This technology has successfully realized the pump inspection operation without killing well and the testing passing annulus without moving pipe string.