川中蓬莱气区超深短尾管悬挂固井技术  

Hanging cementing technology of ultra-deep short liner in Penglai gas field in Central Sichuan

作　　者：李涛 吴杰 徐卫强 文春宇 LI Tao;WU Jie;XU Weiqiang;WEN Chunyu(Engineering Technology Research Institute of Southwest Oil&Gas Company,PetroChina,Chengdu 610017,Sichuan,China)

机构地区：[1]中国石油西南油气田分公司工程技术研究院,四川成都610017

出　　处：《石油地质与工程》2023年第5期104-108,共5页Petroleum Geology and Engineering

基　　金：中国石油天然气集团公司重大现场试验项目“复杂超深井固井密封完整性技术现场试验”(2020F-49);中国石油西南油气田分公司科研项目“万米特深井井身结构及对策性研究”(20220302-07)。

摘　　要：四川盆地川中蓬莱气区灯影组储层埋深超7000 m,PS1井是区域内一口风险探井,目的尾管段固井施工中存在的主要难点为:①裸眼段井径不规则,大肚子井段多,水泥浆量少,冲洗时间短,顶替效率难以保证;②井底温度163℃,气层离喇叭口近,水泥浆需具备抗高温防强度衰退、防气窜、强度发展快等性能;③尾管下入井深超7000 m,尾管段长422 m,重量较轻,倒扣丢手是否成功难以验证,对尾管悬挂器质量及操作要求高。针对存在难点,通过增加冲洗隔离液体积量、强化扶正器安放以提高套管居中度来保证顶替效率;采用加砂柔性防气窜水泥浆体系,并配合憋压候凝的方式,确保水泥浆压稳气层;尾管悬挂器中心管长度加长至2.8 m,降低超深短尾管倒扣丢手验证难度。该井采用∅127 mm尾管悬挂固井,施工顺利,固井质量一界面合格率95.33%,二界面合格率100%,该系列技术在后续2口井进行了推广应用,固井施工顺利,且固井质量良好,为类似超深活跃气层短尾管悬挂固井提供技术借鉴。The buried depth of reservoirs in Dengying Formation of Penglai gas field in central Sichuan Basin exceeds 7000 meters.PS1 well is a high-risk exploration well in the area,and the main difficulties in cementing construction of the target liner are as the follows.①Diameter of the open hole section is irregular,there are many large belly sections,with less cement slurry and short flushing time,and then the replacement efficiency is difficult to ensure.②Bottom hole temperature is 163℃,and the gas layer is close to the bell mouth.The cement slurry needs to have the properties of high temperature resistance,strength decline prevention,gas channeling prevention,and rapid strength development.③The liner is lowered into the well with a depth of more than 7000 m,and the liner section is 422 m long.The weight is relatively light,and it’s difficult to verify whether the reverse buckle release is successful.It has high requirements for the quality and operation of the liner hanger.Therefore,by increasing the volume of flushing and isolation liquid,and strengthening the placement of the centralizer,the casing centralizing degree is improved to ensure the displacement efficiency.By adopting the sand flexible anti gas channeling cement slurry system,combined with the pressure holding and waiting method,it is ensured that the cement slurry can stabilize the gas layer.The length of the central tube of the tail pipe hanger is extended to 2.8 m,reducing the difficulty of the verification of the reverse buckle of the ultra-deep short tail pipe.The cementing construction of∅127 mm liner of this well was smooth,and the qualification rate of the first interface of cementing quality was 95.33%,as for the second interface,it was 100%.This series of technology was popularized and applied in the following 2 wells,achieving smooth construction and good quality,and providing a good technical reference for short liner suspension cementing in ultra-deep active gas reservoir.

关 键 词：蓬莱气区 超深井 短尾管 悬挂固井 中心管 防气窜水泥浆 

分 类 号：TE341[石油与天然气工程—油气田开发工程]