摘要
针对狮70井三开钻遇高压盐水层和漏失层,钻井液不能压稳高压水层,同时井底存在内循环,环空压力系统紊乱,固井期间易发生漏失,高压盐水层不易封固,固井质量难以保证的难题,通过水泥浆性能实验及固井工艺研究,设计了抗高温高密度堵漏水泥浆体系,该体系密度1.88~2.40 g/cm~3,沉降稳定性小于0.03 g/cm~3,SPN值小于3,稠化时间可调,24 h抗压强度大于18 MPa。现场采用正注反挤固井施工工艺,根据施工参数预测出施工需要的水泥浆稠化时间,通过缩短尾浆稠化时间,并在替浆后期降低施工排量的方法,使水泥浆在小排量顶替过程中逐渐稠化凝固,从而达到快速封固高压水层的目的,再通过反挤施工封固漏层以上井段,顺利完成了该井?273.05 mm尾管固井施工,套管鞋及漏层处固井质量优质,盐水层处固井质量合格,为该区块尾管固井积累了成功经验。
In Well Shi-70,drilling of the liner wellbore section encounters both the high-pressure brine layer and thief zone.The drilling fluid cannot balance the high-pressure aquifer.Meanwhile,internal circulation is present downhole and disturbs the annular pressure system.Consequently,cementing is prone to lost circulation,high difficulties are found in sealing the high-pressure brine layer,and cementing quality is associated with high uncertainty.Based on cement slurry performance tests and cementing practice analysis,the high-temperature-tolerant high-density thief-zone-plugging cement slurry system was designed.The system has a density of 1.88-2.40 g/cm~3,with the stability below 0.03 g/cm3,SPN less than 3,adjustable thickening time,and 24 h comprehensive strength of above 18 MPa.The casing/linear injection-annulus squeeze method was adopted in field practices.The required thickening time was estimated from the operation parameters.By reducing the thickening time of the tail slurry and lowering the pump rate in the later stage of slurry displacement,the slurry was gradual thickened and set during the low-rate displacement to rapidly seal off the highpressure aquifer.Then,cement squeeze through the annulus was performed to seal off intervals above the thief zone.Thus,the?273.05 mm liner cementing was successfully completed in this well.The cementing quality at the casing shoe and thief zone was tested to be premium and that at the brine aquifer was also acceptable.The practice provides successful experience for liner cementing in this area.
作者
费中明
党冬红
孔哲
和建勇
蒋世伟
高飞
杨杰
FEI Zhongming;DANG Donghong;KONG Zhe;HE Jianyong;JIANG Shiwei;GAO Fei;YANG Jie(Cementing Company,CNPC Bohai Drilling Engineering Company Limited,Renqiu 062552,Hebei,China)
出处
《石油钻采工艺》
CAS
北大核心
2022年第2期173-177,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科研项目“青海油田深探井固井关键技术研究”(编号:2020ZD15Y-03)。
关键词
尾管固井
溢漏同层
正注反挤
水泥浆
稠化时间
liner cementing
coexistence of well kick and lost circulation
casing/liner injection-annulus squeeze
cement slurry
thickening time
