窄安全密度窗口地层控压下尾管技术研究及应用  

Study and Application of Managed Pressure Technology of Running Casing in Narrow Safety Density Window Formations

作　　者：杨赟 陈倩[1,2] 韦海防 王培峰 唐弢[3,4] 彭元超 马天寿 王玲 YANG Yun;CHEN Qian;WEI Haifang;WANG Peifeng;TANG Tao;PENG Yuanchao;MA Tianshou;WANG Ling(CCDC Drilling&Production Engineering Technology Research Institute,Xi’an Shaanxi 710018,China;National Engineering Laboratory for Exploration and Development of Low-Permeability Oil&Gas Fields,Xi’an Shaanxi 710018,China;Southwest Petroleum University,Chengdu,Sichuan 610500,China;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu,Sichuan 610500,China)

机构地区：[1]中国石油川庆钻探工程有限公司钻采工程技术研究院 [2]低渗透油气田勘探开发国家工程实验室 [3]西南石油大学 [4]油气藏地质及开发工程国家重点实验室

出　　处：《钻采工艺》2022年第3期1-8,共8页Drilling & Production Technology

基　　金：中国石油天然气集团公司科学研究与技术开发项目“先期注水区密闭循环钻完井技术集成试验与推广应用”(编号:2019D-4212);川庆钻探工程有限公司科技项目“低渗透油藏异常压力储层动态平衡压力固井技术研究”(编号:CQ2020B-15-2-3);“注水区井口密闭循环钻井智能控制技术研究”(编号:Q2021B-13-4-3)资助。

摘　　要：在窄安全密度窗口地层下套管过程中,套管柱在井眼中运动产生的波动压力极易诱发井下复杂情况。为保障窄安全密度窗口条件下下套管作业的安全,文章建立了偏心环空下套管瞬态波动压力计算模型,并基于井筒压力平衡关系建立了尾管下入与钻杆送入过程中井筒压力预测与控制模型,分析了作业中井底压力瞬态波动的主要影响因素,开展了现场控压下套管案例研究。研究结果表明,套管下入速度、套管偏心度、钻井液流变参数是影响井底压力波动的主要因素。环空瞬态波动压力随着环空流体流变参数(屈服值、稠度系数、流性指数)、套管下入速度的增大而增大,随着偏心度的增加而减小。并在DB-X井开展了现场试验,建立了控压下套管井筒压力控制图版,计算结果显示当尾管送入速度控制在0.16~0.20 m/s时能有效保障井底安全,该数据指导了本井的现场施工,有效防止了下套管过程中井下复杂的发生。文章的研究结果为下套管速度优化、井底压力控制提供了新思路,对降低窄安全密度窗口地层中下套管施工风险和提高固井质量具有重要意义。In the process of running casing in the narrow safety density window formations,the surge pressure generated by the movement of the casing string in the borehole can easily induce the complicated downhole incidents.In order to ensure the safety of running casing under narrow safety density window,a transient surge pressure calculation model for casing running in eccentric annulus was proposed.The wellbore pressure prediction and management model during the liner running was also proposed based on the wellbore pressure balance relationships.The main influencing factors of bottom hole surge pressure in running casing operation were analyzed and the case study of field running casing for managed pressure cementing was performed.The research results show that the casing running speed,casing eccentricity,and rheological parameters of drilling fluid are the main factors affecting the bottom hole surge pressure.The annulus transient surge pressure increases with the increasing of annulus fluid rheological parameters(yield value,consistency coefficient and fluidity index)and casing running speed,but decreases with the increasing of eccentricity.A case calculation was carried out by taking Well DB-X as an example,and the wellbore pressure control chart of running casing for managed pressure cementing was proposed.The calculation results show that it can effectively guarantee the bottom hole safety when keeping the liner running speed of 0.16~0.20 m/s.The data guide this well operation,effectively prevent the occurrence of downhole complications during casing running.The results of this paper can provide a new idea for velocity optimization of running casing and bottom hole pressure management during cementing,which is of great significance for reducing casing running risk and improving cementing quality in formation with narrow safety density window.

关 键 词：窄安全密度窗口 下套管 波动压力 下入速度 偏心环空 流变参数 

分 类 号：TE256[石油与天然气工程—油气井工程]