摘要
The well cementing is important during the extended reach well drilling and the completion, whereas the displacement efficiency and the interface stability are important to guarantee the success of the cementing. In this paper, the interface stability of the cement slurry is simulated using the computational fluid dynamics software. The calculation results indicate that during the displacement, the length of the displacement interface increases with the increase of the deviation angle. The larger the eccentricity, the more significant the velocity difference, along with a longer displacement interface length, a less stable interface, and a lower displacement efficiency. Therefore, to guarantee the cementing quality and maintain a high displacement efficiency, the eccentricity should be controlled within 0.5. Application of a casing centralizer will dramatically improve the interface stability, decrease the dilution zone length of the interface and thus, is beneficial to the slurry cementing and displacement. The simulations are verified with an average absolute deviation less than 3.76% and the 45? helix angle of the rigid centralizer is recommended. Combining the data of an extended reach well on-site, methods are proposed for improving the displacement efficiency and the interface stability during the well cementing and displacement with complex boreholes. These numerical methods can be used to provide some theoretical guidance for designing the cementing of an extended reach well.
The well cementing is important during the extended reach well drilling and the completion, whereas the displacement efficiency and the interface stability are important to guarantee the success of the cementing. In this paper, the interface stability of the cement slurry is simulated using the computational fluid dynamics software. The calculation results indicate that during the displacement, the length of the displacement interface increases with the increase of the deviation angle. The larger the eccentricity, the more significant the velocity difference, along with a longer displacement interface length, a less stable interface, and a lower displacement efficiency. Therefore, to guarantee the cementing quality and maintain a high displacement efficiency, the eccentricity should be controlled within 0.5. Application of a casing centralizer will dramatically improve the interface stability, decrease the dilution zone length of the interface and thus, is beneficial to the slurry cementing and displacement. The simulations are verified with an average absolute deviation less than 3.76% and the 45? helix angle of the rigid centralizer is recommended. Combining the data of an extended reach well on-site, methods are proposed for improving the displacement efficiency and the interface stability during the well cementing and displacement with complex boreholes. These numerical methods can be used to provide some theoretical guidance for designing the cementing of an extended reach well.
作者
王金堂
孙宝江
李昊
王志远
高永海
Jin-tang Wang;Bao-jiang Sun;Hao Li;Zhi-yuan Wang;Yong-hai Gao(School of Petroleum Engineering, China University of Petroleum (East China), Qingdao 266580, China;National Engineering Laboratory for Testing and Detection Technology of Subsea Equipments, Qingdao 266580, China)
基金
Project supported by the National Basic Research Deve-lopment Program of China(973 Program,2015CB251200)
the National Science and Technology Major Project(Grant No.2016ZX05020-006)
the Changjiang Scholars and Innovative Research Team in University Project(Grant No.IRT_14R58)