松辽盆地南部下白垩统火石岭组煤岩气水平井安全钻井技术  

Safe drilling technology for horizontal wells of coal-rock gas in Lower Cretaceous Huoshiling Formation,southern Songliao Basin

作　　者：孙平涛[1] 邢东洋 欧歌 庞晓东 SUN Pingtao;XING Dongyang;OU Ge;PANG Xiaodong(Oil and Gas Technology Research Institute,PetroChina Jilin Oilfield Company,Songyuan,Jilin 138000,China)

机构地区：[1]中国石油吉林油田公司油气工艺研究院,吉林松原138000

出　　处：《天然气勘探与开发》2025年第1期66-71,共6页Natural Gas Exploration and Development

摘　　要：松辽盆地南部下白垩统火石岭组煤岩气作为非常规油气资源,分布广、储量大,是常规天然气增储上产的重要接替资源。但是该区火石岭组碳质泥岩硬度高且微裂缝发育(多为水平裂缝),当井斜角超过88°时,碳质泥岩井壁会产生大量的大掉块,钻具旋转过程无法将其破碎,且掉块很难被携带至地面,井筒清洁难度大,堆积在井底的掉块会在起下钻过程中造成遇阻甚至卡钻等井下事故,严重时需要封井侧钻。为此,开展了坍塌压力精确预测、钻井液性能优化及防卡措施制订等多项研究。研究结果表明:①借助岩心实验结果及测井数据通过软件建模,对碳质泥岩及煤岩的坍塌压力进行预测,并在导眼施工过程通过地破试验获得地层漏失压力,在此基础上设计钻井液密度,可为井壁提供有效的力学支撑;②通过强化钻井液封堵性、抑制性,并优化钻具组合、制订有针对性的防卡措施,能大幅度地降低卡钻风险,杜绝“卡死”情况发生,在应用过程中成功解决卡钻4次,有效预防卡钻8次,并且水平段长度由287 m延长至765 m,初步解决了该区钻遇碳质泥岩井段易卡钻的难题。结论认为,相关研究成果有助于加快对松辽盆地深层煤岩气勘探开发进程。As an unconventional hydrocarbon resource,the coal-rock gas of the Lower Cretaceous Huoshiling Formation in southern Songliao Basin is characterized by wide distribution and large reserves.It is an important replacement resource of conventional gas.However,in the Formation,the carbonaceous mudstones with high hardness contain developed microfractures which are mostly horizontal.When the wellbore inclination angle reaches more than 88°,a large number of rock fragments will be produced from the carbonaceous mudstone sidewall.These fragments cannot be broken along with the rotation of drilling tools and are difficult to be carried to the ground,making the wellbore cleaning very challenging.The fragments accumulated at the bottom hole may cause downhole accidents such as pipe blocking and even sticking during tripping process.In severe cases,plugging and sidetracking may be required.Therefore,some researches have been conducted on accurate prediction of collapse pressure,optimization of drilling fluid performance,and determination of anti-sticking measures.The results show that the sidewall can be mechanically supported in an effective manner through optimization of drilling fluid density on the basis of prediction of the collapse pressure in carbonaceous mudstones and coal rocks by means of software modeling with the aid of core experiment results and logging data,and determination of formation leakage pressure through leak off test during pilot hole operation.Moreover,the risk of sticking can be greatly mitigated by enhancing the plugging and inhibition capacities of drilling fluid,optimizing the drilling assembly and formulating appropriate anti-sticking measures.During field application,the issue of sticking was successfully resolved four times,and effectively prevented eight times.Additionally,the length of the horizontal section was extended from 287 m to 765 m,initially addressing the sticking problem when drilling through carbonaceous mudstone intervals of this area.The research results are conducive to faci

关 键 词：碳质泥岩 水平井 卡钻 煤岩气 微裂缝发育 硬脆性泥岩 

分 类 号：TE243[石油与天然气工程—油气井工程]