摘要
成6井位于准噶尔盆地中央坳陷东道海子凹陷东斜坡,是一口重点预探直井,设计井深达6990 m。为了提高该区块超深井的钻探成功率,解决复杂井段钻探过程中的井壁稳定及储层保护问题,通过梳理钻井液技术难点,制订了“强抑制—强封堵—稳流变—适密度”技术对策,在优选钻井液处理剂的基础上,构建了甲酸盐抗高温防塌钻井液体系,并通过室内评价实验与现场应用进行了验证。研究结果表明:①室内评价实验结果显示,该钻井液体系具有良好的抗温、抑制、封堵、沉降稳定、抗黏土污染及储层保护性能;②所构建的钻井液体系应用于成6井第三次开钻(以下简称三开)井段,辅以相应的钻井液现场维护处理工艺,取得了良好的应用效果,现场钻进过程中井壁稳定,起下钻畅通无阻,完井作业顺利,满足了工程顺利钻进的要求;③现场应用中,该钻井液体系的流变性稳定,黏度和切力低,钻遇气层后流变性变化不大,高密度条件下仍保持沉降稳定性,井底无沉砂;④该钻井液体系有效解决了井壁稳定及储层保护问题——成6井的井身质量好,三开井段平均井径扩大率为3.25%,电测发现良好油气显示,完井试油日产气量为3.4×10^(4)m^(3);⑤实现了优快钻井,成6井全井机械钻速平均为3.16 m/h,同时取全取准了三叠系和二叠系地质资料,为后续油气勘探开发工作奠定了坚实的数据基础。结论认为,所形成的钻井液技术为该区块油气勘探开发提供了技术保障,对其他区块超深井钻井液的构建及施工亦具有参考意义。
Well Cheng 6,located in the eastern slope of Dongdaohaizi Sag in the central depression of the Junggar Basin,is a key vertical exploration well with a designed depth of 6990 m.In order to improve the success rate of ultra-deep well drilling in this block and address issues of wellbore stability and reservoir protection in the process of drilling complex sections,technical difficulties of drilling fluid were reviewed,and a strategy of“strong inhibition,strong plugging,stable rheology,optimal density”was formulated.Based on optimizing drilling fluid treating agents,a high-temperature-resistant and anti-collapse formate drilling fluid system was developed and verified through laboratory evaluation test and field application.The following results are obtained.(i)The laboratory evaluation test shows that this drilling fluid system performs well in temperature resistance,inhibition,plugging,settlement stability,clay contamination resistance,and reservoir protection.(ii)Applied to the third-spud section of Well Cheng 6,together with corresponding on-site maintenance and treatment processes,the developed drilling fluid system has achieved remarkable application results,ensuring the wellbore stability during drilling process,smooth tripping,and completion operations,meeting the engineering requirements for efficient drilling.(iii)In field applications,the drilling fluid system exhibits stable rheological properties and low viscosity and shear force.The rheological properties change minimally after encountering gas zones;the settlement stability is maintained even under high-density condition,with no sand depositing at the bottom hole.(iv)This drilling fluid system can effectively address issues of wellbore stability and reservoir protection.Well Cheng 6 shows good wellbore quality,with the average hole enlargement rate of 3.25%in the third-spud section.Electric logging reveals good oil-gas shows,and the daily gas production of 3.4×10^(4)m^(3)is obtained during completion testing.(v)Well Cheng 6 has achieved optimal and fast drilling with an average ROP of 3.16 m/h.Meanwhile,the Triassic and Permian geological data have been acquired completely and accurately,providing a solid data base for the following exploration and development.It is concluded that the developed drilling fluid technology provides a technical guarantee for the hydrocarbon exploration and development in this block,and is of reference significance for the construction and implementation of ultra-deep well drilling fluid in other blocks.
作者
王伟
李希君
秦涛
郝泽君
季一冰
邱春阳
WANG Wei;LI Xijun;QIN Tao;HAO Zejun;JI Yibing;QIU Chunyang(Drilling Fluid Technology Service Center,Sinopec Shengli Petroleum Engineering Corporation,Dongying,Shandong 257078,China)
出处
《天然气勘探与开发》
2025年第5期132-141,共10页
Natural Gas Exploration and Development
基金
中国石油化工集团有限公司科研项目“准噶尔盆地钻井提速提效关键技术研究”(编号:P21077-6)。
关键词
准噶尔盆地成6井
超深井
抗高温
高密度
甲酸盐
强抑制
强封堵
井壁稳定
Well Cheng 6 in the Junggar Basin
Ultra-deep well
High temperature resistance
High density
Formate
Strong inhibition
Strong plugging
Wellbore stability
