Research And Applications Of Cement Slurry Shear Stress And Cement Quality Of Second Interface Under Eccentric Condition

During the oil well completion process, the cementing quality of the second interface relates to life of the well, fracturing and production efficiency. The washing capability and cementing strength of the slurry cement of the second interface under different eccentricity are two important factors which influence on the entire cementing quality of the second interface. It is significant to optimize slurry cement system and improve cementing quality that the research of the numerical calculation of the shear stress of second interface and experiment of cementing strength of the second interface under different eccentricity are conductedBased on the governing equations of the laminar flow of the cement slurry in the eccentric annulus, the calculation formulae of the shear stress on the second interface of the slurry cement and the relevant numerical calculation method under eccentric condition were given. Taking toughness, microdilatancy, anti-channeling cement slurry of Jilin Oilfield as examples, the shear stress on the second interface of the three kinds of cement slurry mentioned above under different eccentricity were calculated numerically, through whose analysis, the hole cleaning ability of the three kinds of cement slurry mentioned above was evaluated. With the homemade natural sandstone wellbore models,the laboratory experiments of cement strength on the second interface of the cement slurry under eccentric condition were conducted, through whose analysis of result, the entire cement strength on the second interface of the three kinds of cement slurry mentioned above was evaluated. By the numerical calculation of the shear stress on the second interface of the three kinds of cement slurry mentioned of the second interface shear stress the three kinds of slurry cement mentioned above and analysis and evaluation of the results of laboratory experiments of cement strength, the optimization of the three kinds of cement slurry mentioned above was realized. The order of optimization is microdilatancy, anti-channeling, toughness cement slurry.