摘要
通南巴构造高压气井钻井在很多方面具有世界级的难度 ,破岩能量、清岩能力不足引起大尺寸井眼机械钻速低 ,速度慢、井眼不畅通 ,造成大量事故复杂。复合钻配合PDC或强保径高转速牙轮、大钻杆、大钻铤 ,可以有效地提高速度。工具成本在总成本中所占份额较小 ,中空分流、加长直螺杆是常规的消耗料。对井斜、井底水平位移的限制应适当放开 ,力学平衡是保持上部层段井壁稳定的关键 ,保持井壁稳定的钻井液密度应随井径的变化而变化。井漏处理时要注意保持尽量高的液柱压力 ,注意喷漏转换。含硫气井井控难度远高于油井 ,设备的气密封能力一般低于油密封能力 ,工作中应重点注意压稳地层内流体 。
It is most difficult in the world to drill the high pressure gas wells in Tong Nan Ba structure,insufficient rock broken and cleaned capacities causing a low speed in drilling a large size borehole and a great number of accidents raising from well sloughing.The drilling speed may be effectively raised through applying the combination drill coordinating with PDC or strong gauge and high rotary speed cone and the large diameter drill pipe and collar,etc.The tool cost takes a relatively small share in the total drilling cost and the extended straight screw rod for shunting through perforating is the commonly consumable material.The limits on hole deviation and bottomhole horizontal displacement should be properly relaxed.Mechanical balance is the key of maintaining the sidewall stabilization in the upper intervals and the drilling fluid density should be changed with the change in hole diameter in order to maintain the sidewall stabilization.When treating lost circulation,we should pay attention to maintaining the liquid column pressure as high as possible and to the blowout lost circulation transform.The difficulty of controlling sour gas well is much higher than that of controlling oil well and the capability of sealing gas in equipment is generally lower than that of sealing oil.In operation,we should pay more attention to suppressing stably the fluids in the formation and adopt some special measures to raise the control capability and treatment velocity.
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2003年第2期50-53,共4页
Natural Gas Industry
