微型多分支钻管延伸距离影响因素

Influencing factors of extension distance of micro multi-branch pipe

 李雷¹ 王方祥² 李天阳²

中国石油大学胜利学院油气工程学院，山东 东营 257000 中国石油大学（华东）石油工程学院，山东 青岛 266580）

College of Petroleum Engineering, Shengli College, China University of Petroleum, Dongying 257000, China School of Petroleum Engineering, China University of Petroleum, Qingdao 266580, China)

 钻管穿出轨道的距离决定着微型多分支增产技术的效果。根据微型多分支技术的工艺原理，建立了钻管穿出轨道的有限元模型。文中基于瞬态动力学理论进行计算，利用钻管应力和弯曲度2个评价参数，分析了不同轨道类型和钻管参数的影响规律。室内实验结果表明：初始段曲率半径相对较大、整个轨道曲率半径变化平稳的轨道，对应的钻管应力和弯曲度较小；轨道出口角度从30°增大至60°时，钻管应力和弯曲度逐渐增大；轨道间隙从2 mm增大至10 mm时，钻管应力和弯曲度逐渐减小；随钻管直径与壁厚增大，钻管应力和弯曲度增大；地层对钻管起矫直作用，间接增加了钻管的延伸距离。针对不同的油层厚度，应选择出口角度不同的轨道，保证贯穿整个油层，并最大化泄油面积。基于瞬态动力学的钻管穿出轨道数值模拟，为微型多分支增产工具参数优选提供了理论依据。

 The distance of the pipe that penetrates out of orbit determines the effect of micro multi-branch stimulation technology. According to the technique of multi-branch, the finite element model of the pipe that penetrates out of orbit was established. The influence of orbit parameters and pipe parameters on the pipe′s stress and curvature were analyzed based on transient dynamics theory, and the results were verified by the laboratory experiment. The results show that the stress and curvature of the pipe, where the orbit′s initial curvature radius is relatively larger and the curvature radius changes more smoothly, is smaller. The stress and curvature of the pipe increase as the exit angle increases from 30° to 60°. The stress and curvature of the pipe decrease as the gap increases from 2 mm to 10 mm. The stress and curvature of the pipe increase as the diameter and wall thickness of pipe increase. The formation has straightening effect on pipe and can increase the stretch distance of pipe. For different reservoir thicknesses, the different orbits with different exit angles should be selected to ensure the maximum oil drainage area. The numerical simulation method based on the transient dynamics provides a theoretical basis for parameter optimization of micro multi-branch stimulation tool and can accelerate the application of this technique.

10.6056/dkyqt201703030