致密高应力水平井优快钻完井难点与对策

Difficulties and solutions of optimized fast drilling and completion of horizontal well in tight and high stressed formation

中江气田致密气藏地质条件复杂,岩石硬度大,地层压力高,井壁稳定性差。钻井过程中井壁易垮塌,长裸眼段摩阻大,斜井段机械钻速低,钻完井周期长,成本居高不下,降本优化空间有限,制约了该区的开发效益。针对该问题,文中总结了钻遇沙溪庙组目的层的主要技术难点,结合钻井实践,从维护井壁稳定的处理剂、水平段长度、井身结构、提速技术、建井模式等方面提出了致密高应力水平井钻完井技术对策,以期为后期中江气田钻井的提速和降本增效提供技术支撑。

The Zhongjiang tight gas reservoir are characterized by complicated geological condition,high hardness value of rock,high formation pressure and wellbore instability.In the drilling process,it has the problems such as wellbore instability,large friction in long open hole section,low penetration rate in the inclined section and long drilling cycle,which leads to high cost and limited space for cost-reducing optimization and restricts the exploitation benefit of this area.In view of these problems,the main drilling technical difficulties in the target stratum of Shaximiao Formation are summarized.Combined with the drilling practice,the drilling technical solutions for tight and high stressed horizontal well are put forward from the aspects of treating agent for maintaining wellbore stability,horizontal section length,well structure and the mode of well construction,which will provide the technical support for fast drilling,cost saving and efficiency increasing of Zhongjiang Oilfeild.