渤海油田中曲率半径侧钻井关键技术

Key Technology of Mid-Curvature Radius Sidetracking Well in Bohai Oilfield

随着渤海油田的不断开发,高含水和高采出程度是油田开发中面临的主要问题。近年来,利用老井侧钻中曲率半径平井技术是解决渤海油田平台槽口和在生产井控制储层面积有限问题、降低开发成本、进一步挖潜剩余油、提高油田产能的有效技术手段。由于中曲率半径侧钻井在钻完井工程中存在轨迹曲率半径小、套管开窗、过窗难度大、导向钻具疏松地层定向困难、套管下入摩阻大等难题,从轨迹设计、开窗工具优化、钻具组合设计、钻井摩阻水力学分析、下入管柱结构优化等方面形成了渤海油田中曲率半径侧钻井工艺体系。通过实际应用,证明该技术成功解决了该类型井靶前位移不足的问题,为海上油田安全、高效实施提供技术支撑,大大缩短了钻完井工期,节省了费用,提供了海上油田“挖潜剩余油”的新思路,对同类型井具有较强的指导意义和推广前景。

With the continuous development of Bohai oilfield,high water content and high production degree are main problems faced in the development of oilfields.In recent years,the use of horizontal well technology of mid-curvature radius in old well side drilling is an effective technical means to solve the limited area at the notch of Bohai oilfield platform and the control reservoir area in the produc⁃tion well,reduce the development cost,further excavate the remaining oil potential,and improve the production capacity of the oilfield.Due to the difficulties in the drilling and completion engineering of horizontal wells with medium radius of curvature,such as the small radius of trajectory curvature,the difficult casing windowing and crossing window,the difficult orientation in loose formation of steering drilling tool,the large casing running friction and so on,the drilling and completion process system with medium radius of curvature in Bohai Oilfield has been formed from the aspects of trajectory design,windowing tool optimization,BHA design,drilling friction hydrau⁃lics analysis,running string structure optimization and so on.This drilling process system provides a technical support for the safe and efficient implementation of this type of well,shortens the drilling and completion period and saves the costs,and presents a new idea of"tapping potential remaining oil"in offshore oil fields,possessing strong guiding significance and popularization prospect for the same type of wells.