北部湾盆地探井提速提效技术及应用

Technology and Application of Increasing DrillingSpeed and Efficiency in Beibu Gulf Basin

北部湾盆地油气资源丰富,但地层构造分布零散,断层发育,地层坍塌压力高,钻进期间易发生井漏,目的层裸眼段长,经常钻遇抗压强度高的花岗岩。钻探面临着井位转换频繁、地层易垮塌及漏失、海上油基钻屑处理难度大、花岗岩机械钻速低、弃井时效低等问题。为进一步降低钻探周期及作业成本,采用“一孔双眼”勘探模式、井身结构优化技术、海上油基钻屑处理技术、新型复合冲击钻井提速技术、长裸眼段一次性水泥塞弃井工艺、水泥伞悬空水泥塞技术等提速提效措施,有效解决了南海西部海域钻探难题,且在实际应用中效果显著,提高了勘探及钻井作业时效,为同类型油气田钻探提速提效提供参考。

Beibu Gulf Basin is rich in oil and gas resources,but the stratigraphic structure is scattered,and is characterized by developed faults,complex ground stress,high formation collapse pressure,developed granite with high compressive strength.Drilling is faced with such problems as frequent well positions conversion,formation collapse and leakage,difficulty in offshore oil-based drilling cuttings treatment,low penetration rate of granite machinery,and low wells abandonment efficiency of long open hole.The"one hole and two eyes"exploration mode,wellbore structure optimization technology,offshore oil-based drilling cuttings treatment technology,new composite impact drilling speed increasing technology,one-time cement plug abandonment technology in long open hole section,cement umbrella suspended cement plug technology and other efficiency improvement and speed improvement measures were adopted in order to further reduce drilling cycle and operating costs.It has effectively solved the drilling problems in the western waters of the South China Sea,and has achieved remarkable results in practical application,improving the exploration aging and drilling speed,and providing a reference for improving the speed and efficiency of drilling in the same type of oil and gas fields.