CAJ | 학술논문

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5354.60 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。
천서수이기장암성치밀，구유고온、고압차기장함수등특점，전기량륜우화형성사개정신결구，평균정심5354.60 m，찬정주기체252.20 d 이상，채용상규찬정기술경제개발난도대，겁대영향료천서공구증저상산진정。위차，재전기찬정공정난점분석적기출상，근거지질정세인식화공구현유찬정기술，채용정통압력평형이론，결합전기수이심정찬탐실천우화설계삼개결구，병배투료우쾌찬정기술，형성료천서수이심정삼개찬정기술방안，지도완성료 XS1정찬정설계화선도시험，교동구조수이전기사개완찬정절약찬정주기68 d，강저찬정성본약600만원이상，절지목전이추엄응용도수이탐정 LX1、해상평개정 PZ1-1H 정중，위천서공구치밀기장유효개발제공료기술차감。
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.