青海油田第一口分支水平井钻完井工程实践

Drilling and completion operation practice of first multilateral horizontal well in Qinghai Oilfield

为进一步提高单井产量,青海油田计划使用双分支水平井来开采东坪地区的基岩气藏,针对该地区基岩钻进过程中漏失较严重,开窗位置泥岩坚硬以及甲方提出的分采要求等技术难题,通过优化井身结构、优选分支井钻完井方案以及定位、开窗、斜向器回收、重入和分采配套工具优化研究,形成了适合基岩油气藏开发的三开井身结构,具有抗拉、抗扭和耐压能力的定位工具,并配套斜向器的合理使用,顺利地完成了该井的完井施工,投产后日产气最高达76×104 m3,成为青海油田60年来单井产量最高的井,为基岩气田经济高效开发探索出一条新的技术途径。

In order to further increase the production output per well, Qinghai Oilifeld plans to use the double multilateral horizontal well mode to exploit the base-ment gas reservoir in Dongping. In consideration of the technical dififculties existing in this area, such as relatively serious leakage in drilling operation, hard mudstone at the window-opening position as well as the slice mining requirements brought forth by ifrst party, and through optimization of wellbore structure, proper selection of multilateral well drilling and completion program, positioning process, window opening process, whipstock recovery, re-entry and selective mining process and supporting tools, these technical dififculties have been settled, and the multilateral well drilling and completion technology applicable to development of Base-ment oil-gas reservoir has been formed. In the ifeld application, the completion operation of such well has been completed smoothly. After being put into service, this well has got the daily gas production of 76×104 m3, becoming the well with the highest production output in Qinghai Oilifeld over 60 years. As a result, the expected effect has been achieved, and a new technical approach for highly-efifcient development of base-ment gas ifelds has been found.