塔河油田碳酸盐岩侧钻小井眼钻完井技术

Drilling and Completion Technology for Sidetracked Slimhole in Carbonate Reservoir in Tahe Oilfield

塔河油田碳酸盐岩储层缝洞发育、非均质性强,受老井井身结构限制,?177.80与?193.70 mm套管开窗后侧钻井眼尺寸小,小尾管固井难度大,二开钻具难以配套。为此,油田进行了深井侧钻小井眼二开次钻完井技术研究,优化钻完井方案,包括?177.80 mm套管开窗侧钻钻完井和?193.70 mm套管开窗侧钻钻完井方案,同时配套小尾管窄间隙固井工艺和小井眼定向钻井技术,研发了封隔地层的牵制式尾管悬挂器和非标套管,确保重叠段的密封性和套管段封隔水层的可靠性。现场应用结果表明:该技术固井整体优良率达85%,经济效益可观,?177.80 mm套管开窗侧钻约为3级结构新井成本的55%~69%,?193.70 mm套管开窗侧钻约为新井成本的61%~68%,推广应用前景广阔。深井侧钻小井眼二开次钻完井技术可为塔河油田碳酸盐岩储层的多次开发提供技术支撑。

The carbonate reservoir in Tahe Oilfield features with developed fractures and caves and strong het-erogeneity. Constrained by the wellbore configuration of the drilled wells, the sidetracked hole in the cased hole completed with 0177. 80 and 0193. 70 mm casing is small, leading to challenging liner cementing operation and drill string selection in the second spud. To address the issues, the drilling and completion technology for the sec-ond spud of deep well slimhole sidetracking have been studied. The drilling and completion program optimization has been conducted, including that of the cased hole completed with 0177. 80 mm or 0193. 70 mm casing. In view of cementing of small liner with narrow annular and slimhole directional drilling technology, a hold-down sub type liner hanger and non-standard casing has been developed to ensure the seal of the overlap section and water layer sealing reliability of casing section. Field application results show that ： the technical benefits are considerable, the cost of sidetracking in mm casing is about of the similar new drilled well and the cost of sidetmcking in 0193. 70 mm casing is about 61%？6 8 % of that of new drilled well, presenting broad application promo- tion prospects. The study could provide technical support for the multiple development of carbonate reservoir in Tahe Oilfield.