裸眼事故复杂高压气井注侧钻水泥塞技术

Pumping Cement Slurry and Drilling Set Cement Plug in High Pressure Open Hole Gas Well

SBC-200井是委内瑞拉东部油气田的一口复杂油气井,三开φ244.5 mm技术套管下深4864 m,四开φ215.7mm井眼钻至4945.12 m卡钻,多种方法处理未解卡,套铣爆破松扣,鱼顶深度4897.56 m。使用的油基钻井液体系密度为1.415g/cm3时发生油气侵,密度为1.44 g/cm^3时建立井下压力平衡,当量密度1.49 g/cm^3发生井漏。为了完成钻井进尺,对鱼顶以上35.53 m裸眼井段实施水泥回填侧钻。固井采用高致密、高强度、低失水水泥浆,复合功能前置液体系及相应工艺技术措施,完成注水泥塞作业,满足侧钻质量要求。

Well SBC-200 is a complex well drilled in a oil and gas field in east Venezuela. Technical casing of φ244.5 mm was run to 4,864 m in this well. Pipe sticking was encountered when drilling the 4th interval (hole size φ215.7 mm) to 4 945.12 m, and several methods of freeing the pipe sticking were tried and failed. Breaking out by explosion was performed and the top of the fish was at depth of 4,897.56 m. Gas cut occurred during drilling with an oil base drilling fluid of 1.415 g/cm^3, and was stopped when mud density was 1.44 g/cm^3. Mud losses occurred when mud density was 1.49 g/cm^3. In order to drill to the designed depth, the open hole 35.53 m above the top of the fish was filled with cement slurry and the well was sidetracked. The well was finally cemented with a cement slurry of high density, high strength and low filtration rate. The cement plug was made to satisfy the needs of sidetracking, using prepad with complex functions and techniques suitable for the well conditions.