In order to solve the technical problems such as lost circulation,overflow,low ROP and long drilling periods in the drilling of horizontal wells in the deep buried hills of the Nanpu No.2 Structure, drilling and completion techniques for horizontal wells in deep buried hills were studied.According to geo-mechanical and geological characteristics of strata,the pressure sensitivity of buried-hill reservoirs,and the problems of lost circulation and overflow,the fourth and fifth casing programs were designed for the hori-zontal wells in deep buried hills.Further,a"three build-up and seven sections"borehole trajectory,i.e.,"vertical—build-up—holding—build-up—holding—build-up—horizontal"was designed for such wells.The deflecting tool with rated temperature of 175 ℃,MWD monitoring instrument,and high temperature(220 ℃) oil-in-water drilling fluid system were selected.Application studies on micro-flow precise pressure manage-ment for horizontal wells and completion techniques with high-temperature gel valve were performed.Then a set of drilling and completion techniques suitable for horizontal wells in deep buried hills of Nanpu No.2 Structure were formed.Those techniques have been used in the drilling operations of 15 horizontal wells, with well depths achieving 5 600.00 m,and horizontal displacement over 4 000.00 m,in deep buried hills of Nanpu No.2 Structure,in which complexities like lost circulation and overflow were effectively controlled. Using the modified drilling and completion techniques resulted in achieving safe and high efficient develop-ment of deep buried-hill reservoirs in the Nanpu No.2 Structure,and the potential for continuing to achieve additional improvements.%为了解决南堡2号构造深层潜山水平井钻井过程中井漏、溢流、机械钻速慢和钻井周期长等技术难题,开展了深层潜山水平井钻井完井技术研究.根据地层地质特点、潜山储层压力敏感性和井漏、溢流等情况,深层潜山水平井设计为四开和五开井身结构,设计采用"直—增—稳—增—稳—增—水平"七段式井眼轨道,优选了抗175 ℃的造斜工具、M WD监测仪器和抗220 ℃的水包油钻井液,并开展了水平井微流量精细控压技术及抗高温冻胶阀完井技术的应用研究,形成了适用于南堡2号构造深层潜山的水平井钻井完井技术.南堡2号构造15口深层潜山水平井钻井完井情况表明,井漏和溢流等井下复杂情况得到了有效控制,完钻井深最深达5600.00 m,水平位移最大超过了4000.00 m.潜山储层水平井钻井完井技术实现了南堡2号构造深层潜山储层的安全高效开发,具有较好的推广应用价值.
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