石油学报 ›› 2016, Vol. 37 ›› Issue (9): 1179-1186.DOI: 10.7623/syxb201609013

• 石油工程 • 上一篇    下一篇

基于井壁稳定控制建立井眼轨迹优化预测模型

高佳佳1, 邓金根1, 闫伟1, 冯于恬2, 王厚东1, 李扬1   

  1. 1. 中国石油大学油气资源与探测国家重点实验室 北京 102249;
    2. 中海石油(中国)有限公司天津分公司渤海石油研究院 天津 300450
  • 收稿日期:2015-11-13 修回日期:2016-06-02 出版日期:2016-09-25 发布日期:2016-09-30
  • 通讯作者: 邓金根,男,1963年8月生,1983年获华东石油学院学士学位,2000年获石油大学(北京)油气井工程专业博士学位,现为中国石油大学(北京)博士生导师、长江学者特聘教授,主要从事石油工程岩石力学方面的研究。Email:dengjingen@126.com
  • 作者简介:高佳佳,男,1989年2月生,2011年获西南石油大学学士学位,现为中国石油大学(北京)博士研究生,主要从事多孔弹性介质井壁稳定与防砂方面研究。Email:yiyingtuoli@163.com
  • 基金资助:

    国家自然科学基金项目“压裂液作用下页岩储层的摩擦特性及其对缝网形成的影响”(No.51504267)和国家自然科学基金项目“页岩气钻探中的井壁稳定及高效钻完井基础研究”(U1262201)资助。

Establishment of a prediction model for the borehole trajactory optimization based on controlling wellbore stability

Gao Jiajia1, Deng Jingen1, Yan Wei1, Feng Yutian2, Wang Houdong1, Li Yang1   

  1. 1. State Key Laboratory of Petroleum Resource & Prospecting, China University of Petroleum, Beijing 102249, China;
    2. Bohai Oilfield Exploration and Development Institute, Tianjin Branch, CNOOC China Limited, Tianjin 300450, China
  • Received:2015-11-13 Revised:2016-06-02 Online:2016-09-25 Published:2016-09-30

摘要:

通过线性规划最优解理论及井壁剪切破坏条件,建立了井眼轨迹优化的控制方程及提出相应的数值求取方法。研究表明:当地应力大小关系满足控制方程的临界条件时,正断层作用应力区域钻直井或沿水平最小地应力方位钻水平井时,两者井壁稳定性相同,该情形也发生在逆断层作用应力区域钻直井或沿水平最大地应力方位钻水平井,此外,走滑断层作用应力区域,水平井沿水平最大或最小地应力方位钻进时,其井壁稳定性 也存在相同的可能性;另外,当水平最大地应力与上覆岩层压力比一定时,水平地应力比值(σh/σH)越大,正断层作用应力区域沿水平最小地应力方位,及逆断层作用应力区域沿水平最大地应力方位钻进的最优井斜角越小,反之,走滑断层作用应力区域,水平井的最优钻进方位与水平最大地应力方位夹角越 大。研究成果有助于指导现场施工高效钻进。

关键词: 断层作用应力区域, 井壁稳定, 剪切破坏, 井眼轨迹优化, Mohr-Coulomb准则

Abstract:

Based on the linear programming optimal solution theory and the shear failure criterion of wellbore, the present study establishes the governing equations of borehole trajectory optimization, and also proposes the corresponding numerical seeking method. The research discovers that when the magnitudes of in-situ stresses satisfy the critical condition of governing equations, the wellbore stability of vertical well is equal to that of drilling horizontal well in the direction of the minimum horizontal in-situ stress under the normal faulting stress region. However, as regard to the reverse faulting stress region, the wellbore stability of vertical well is identical to that of drilling horizontal well in the direction of the maximum horizontal in-situ stress. In addition, under the strike-slip faulting stress region, the wellbore stability condition concerning horizontal well where drilling in the direction of the maximum horizontal in-situ stress may be similar to that of the minimum horizontal in-situ stress. Besides, provided the ratio of the maximum horizontal in-situ stress to the overburden pressure holds constant, the higher ratio of the minimum to the maximum horizontal in-situ stress (σh/σH) indicates that the optimum inclination angle is smaller where drilling along the direction of the minimum horizontal in-situ stress under the normal faulting stress region whereas the direction of the maximum horizontal in-situ stress under the reverse faulting stress region. Contrarily, when σh/σH is smaller, the angle between the optimum drilling azimuth and the maximum horizontal in-situ stress direction where drilling horizontal well would become larger under the strike-slip faulting region. This research is helpful for improving the efficiency of drilling process in field.

Key words: faulting stress region, wellbore stability, shear failure, borehole trajectory optimization, Mohr-Coulomb criterion

中图分类号: