川西须二深井三开钻井技术及先导试验

Third spud section drilling technology and pilot test for Xu-2 deep well in West Sichuan

何龙 朱礼平 欧彪 王希勇

HE Long ZHU Liping OU Biao WANG Xiyong

中国石化西南油气分公司钻井工程处，四川成都　610041 中国石化西南油气分公司工程技术研究院，四川德阳　618000

Drilling Engineering Department of Southwest Oil & Gas Company, SINOPEC, Chengdu 610041, China Research Institute of Engineering Technology of Southwest Oil & Gas Company, SINOPEC, Deyang 618000, China

川西须二气藏岩性致密，具有高温、高压且气藏含水等特点，前期两轮优化形成四开井身结构，平均井深5 354.60 m， 钻井周期达252.20 d 以上，采用常规钻井技术经济开发难度大，极大影响了川西工区增储上产进程。为此，在前期钻井工程难点分析的基础上，根据地质精细认识和工区现有钻井技术，采用井筒压力平衡理论，结合前期须二深井钻探实践优化设计三开结构，并配套了优快钻井技术，形成了川西须二深井三开钻井技术方案，指导完成了XS1 井钻井设计和先导试验，较同构造须二前期四开完钻井节约钻井周期68 d，降低钻井成本约600 万元以上，截至目前已推广应用到须二探井LX1、海相评价井PZ1- 1H 井中，为川西工区致密气藏有效开发提供了技术借鉴。

The proven gas reserves of Xu-2 gas reservoir in West Sichuan part is up to 1.211×1 011 m3, and the burial depth of the reservoir is over 4 500 m; the rock is tight, and is characterized by high temperature, high pressure and gas pool containing water. The previous two rounds of optimization led to a 4th spud section wellbore configuration; the average well depth was 5 354.60 m, and drilling cycle was over 252.20 d. So it is of great difficulty to develop the gas pool using conventional drilling technology, hence greatly affecting the process of reserve growth in West Sichuan work area. For this purpose and based on the previous analysis of drilling difficulties, this paper optimized the design of 3rd spud section configuration according to fine understanding of geology and the available drilling technologies in the work area, using the wellbore pressure balance theory and combining the previous practice in drilling of Xu-2 deep well, and provided fast drilling technology and formed a 3rd spud section drilling program for Xu-2 deep well in West Sichuan; the paper also directed and completed drilling design and pilot test for XS1 Well, and compared with previous 4th spud section drilling of the same structure, the drilling cycle was shortened by 68 d, and drilling cost was reduced by over 6 million Yuan. Up to now, the technology has been used in the drilling of Xu-2 exploration well LX1 and marine appraisal well PZ1-1H, providing technical reference for effective development of tight gas pools in the work area in West Sichuan.

10.13639/j.odpt.2015.02.005