Research On The Technology Of Improving Cementing Quality In Horizontal Well With Complicated Trajectory

Due to the development of drilling technology, the number of complex track of horizontal Wells is greatly increased. Because the well structure is complex and changeable,In the cementing design and construction of the interaction between various factors,cementing quality caused a great impact. In this paper, the influence factors of horizontal well in complex trajectory are analyzed and studied, and the technical scheme for improving the cementing quality of horizontal well with complex trajectory is found.Through analysis, the improvement of the cementing quality of horizontal well in complicated trajectory can be studied from the following four aspects: the study of casing under-loading mechanics, the improvement of displacement efficiency, the optimization of cement slurry system and the cementing technology, The mechanical study of columns is the basis for improving the eff-iciency of displacement. The mathematical model of the casing string and the well bore structure is established, and the structure of the casing string is optimized to achieve the best combination of casing centering and annular over current performance. Improve the bond strength of one or two interface, optimize the rinse liquid and various cement slurry formula, and finally get a complete system of cement slurry, to achieve the cleaning solution to clean the cement interface, cement slurry performance and stability to seal the target. Site construction technology, to avoid due to process or unexpected events such as cementing quality,and to develop a complete set of construction support technology.Through technical research and field application test, complex trajectory horizontal well cementing technology is obtained, which provides technical theory support for improving the cementing quality of such wells. The optimization design of casing string, the optimization of cement slurry and the construction guarantee measures are described and demonstrated in detail in this paper. In accordance with the above technical measures, the cementingquality of the final horizontal well sealing section Well ratio increased to more than 70%, compared to the previous year the proportion of high-quality horizontal wells increased by 20 percentage points or more.