摘要
磴探1井尾管固井一次封固段长2235 m,地层承压能力低,漏失风险大,井眼大且不规则,顶替效率难以保证;裸眼段下部油层段长、上部水层多、层间间断短,压稳难度大;疏松砂岩地层井壁与水泥浆胶结质量差,层间封隔易失效。通过提高地层承压能力、清洁井眼、降低固井施工漏失风险,优化浆柱结构、合理加放扶正器提高固井顶替效率;采用双密三凝水泥浆体系和环空加压工艺压稳油气水层;采用界面增强型冲洗隔离液和微膨胀韧性水泥浆体系提高二界面胶结质量。微膨胀韧性水泥浆体系浆体流动度22 cm,稠化时间在设计范围内且可调,滤失量小于50 mL,游离液为0,沉降稳定性0.01 g/cm^(3),膨胀率大于0.4%,弹性模量小于6.0 GPa,水泥石抗压强度发展迅速,24 h抗压强度达30 MPa以上,满足深探井油层尾管固井技术要求,确保了磴探1井Ø139.7 mm尾管固井质量,为后续该区块深探井固井提供了技术借鉴。
The primary cementing section of liner cementing of Well Dengtan 1 is 2235 m long,the formation bearing capacity is low,the leakage risk is great,the borehole is large and irregular,and the displacement efficiency can be hardly guaranteed.The open hole is long in the lower oil layer,there are many water layers in the upper part,interlayer breaks are short,and the stabilization difficulty is great.The bonding quality of slurry to unconsolidated sandstone and well wall is poor,and interlayer isolation tends to fail easily.In this paper,the cementing displacement efficiency was improved by increasing the formation bearing capacity,cleaning the borehole,reducing the leakage risk of cementing construction,optimizing the structure of slurry column and adding centralizers reasonably.Oil,gas and water layers were stabilized by using the two-density three-setting slurry system and the annulus pressurization technology.The bonding quality of the second interface was improved by adopting the interface enhanced flushing spacer and the micro-expansion toughness slurry system.The slurry fluidity of micro-expansion toughness slurry system is 22 cm,its thickening time is adjustable within the design range,the filtration loss is less than 50 mL,the free liquid is 0,the settlement stability is 0.01 g/cm^(3),the expansion rate is larger than 0.4%,the elastic modulus is smaller than 6.0 GPa,and the compression strength of set cement develops quickly to be over 30 MPa after 24 h,which meet the technical requirements of liner cementing of deep exploration well and ensure the quality ofØ139.7 mm liner cementing in Well Dengtan 1.The research results provide a beneficial reference for the following cementing of deep exploration wells in this block.
作者
高飞
田宝振
费中明
党冬红
马巍
刘学敏
GAO Fei;TIAN Baozhen;FEI Zhongming;DANG Donghong;MA Wei;LIU Xueming(No.1 Cementing Company,CNPC Bohai Drilling Engineering Company Limited,Renqiu 062552,Hebei,China;Cooperative Oil and Gas Development Company,CNPC Bohai Drilling Engineering Company Limited,Tianjin 300457,China)
出处
《石油钻采工艺》
CAS
北大核心
2021年第6期727-731,共5页
Oil Drilling & Production Technology
基金
中国石油集团渤海钻探工程有限公司“华北油区长封固段固井工艺技术研究”(编号:2021ZD24Y-01)。
关键词
深井
固井
探井
尾管
水泥浆
隔离液
钻井液
deep well
well cementing
exploration well
liner
slurry
spacer fluid
drilling fluid
