南海东部恩平21−4油田超深大位移井钻井液技术  

Drilling Fluid Technology for Ultra-Deep Extended Reach Wells in Enping 21−4 Oilfield,Eastern South China Sea

作　　者：马积贺 耿铁[1,2] 宋晓伟 狄明利 杨波[1,2] MA Jihe;GENG Tie;SONG Xiaowei;DI Mingli;YANG Bo(China Oilfield Services Limited,Langfang,Hebei,065201,China;CNOOC Key Laboratory of Offshore Driling Fluids and Cementing,Langfang,Hebei,065201,China)

机构地区：[1]中海油田服务股份有限公司,河北廊坊065201 [2]中国海洋石油集团有限公司海上钻完井液与固井重点实验室,河北廊坊065201

出　　处：《石油钻探技术》2025年第2期21-29,共9页Petroleum Drilling Techniques

基　　金：中国海洋石油集团有限公司海上钻完井液与固井重点实验室科研项目“浅层大位移井钻井液工艺及模拟评价技术研究”(编号:YHB23YF007)资助。

摘　　要：南海东部恩平21−4油田是典型的边际油田,超深大位移井钻井过程中存在井眼难以清洁、疏松砂岩承压能力低、钻遇多条断层、摩阻扭矩高和下套管易遇阻等风险挑战。为解决该油田钻井中存在的问题,选择BIODRILL S合成基钻井液,优选了合成基液、降滤失剂、流性调节剂和润滑剂,优化了乳化剂加量,调整了BIODRILL S合成基钻井液配方。室内性能评价结果表明,BIODRILL S合成基钻井液流变性能稳定,具有较高的低剪切速率,抑制性强,封堵性、抗污染性和润滑性能优异,高温高压滤失量2.4 mL,极压润滑系数0.03~0.06,满足恩平21−4油田超深大位移井钻井要求。按该配方配制的BIODRILL S合成基钻井液及研究的关键配套技术在南海东部超深大位移井A1H井、EP−X井进行了现场试验,结果表明:BIODRILL S合成基钻井液性能稳定,具有较好的携岩能力,润滑性能优异,钻进ϕ311.1 mm井眼时摩阻系数为0.17~0.21,下入ϕ244.5 mm套管时裸眼摩阻系数为0.40~0.45,钻井过程顺利。BIODRILL S合成基钻井液技术不但解决了南海东部超深大位移井的钻井难点,还为该海域万米级大位移井安全钻井提供了技术手段。Enping 21−4 in the Eastern South China Sea is a typical marginal oilfield.Certain risks and challenges are faced while drilling of ultra-deep extended reach wells in this oilfield,such as difficult hole cleaning,low pressure bearing capacity of unconsolidated sandstone,multiple faults encountered while drilling,large drag and torque,and restrictions during casing running,etc.In order to solve the drilling problems in this oilfield,BIODRILLS synthetic base drilling fluid was selected and optimized.The optimal synthetic base fluid,filtrate reducer,flow pattern regulator,and lubricant were determined,and the emulsifier dosage was optimized.The formula of BIODRILLS synthetic base drilling fluid was adjusted.The laboratory performance evaluation results show that the formula can maintain good and stable rheological properties,higher low shear rate,strong inhibition,plugging property,anti-pollution property,and excellent lubrication performance,with high temperature and high pressure filtration loss of 2.4 mL and extreme pressure lubrication coefficient of 0.03-0.06,and meet the requirements of ultra-deep long extended reach well drilling in Enping 21−4 Oilfield.The BIODRILLS synthetic base drilling fluid prepared according to the formula has been applied in the ultra-deep extended reach wells A1H and EP−X in the eastern South China Sea.The application shows that the system has stable performance,good cutting carrying capacity,and excellent lubrication performance.The drag coefficient during drillingϕ311.1 mm hole is 0.17-0.21,and the open hole drag coefficient is 0.40-0.45 when runningϕ244.5 mm casing.The drilling fluid has not only effectively solved the drilling problem of ultra-deep extended reach wells in the eastern South China Sea but also provided technical means for the drilling of 10000-meter long extended reach wells in this sea area.

关 键 词：合成基钻井液 低剪切速率 井壁稳定 摩阻 超深大位移井 恩平21−4油田 

分 类 号：TE254[石油与天然气工程—油气井工程]