层理性地层钻井稳定性分析模型  

Analysis Model of Borehole Stability in Bedding Formations

作　　者：丁立钦 王志乔[1,2,3] 王瑜[1,2] 刘宝林[1,2] 吕建国[1] DING Li-Qin WANG Zhi-Qiao WANG Yu LIU Bao-Lin LiJ Jian-Guo(School of Engineering and Technology, China University of Geosciences, Beijing 100083, China Key Lab on Deep Geo-drilling Technology of the Ministry of Land and Resources, China University of Geosciences, Beijing 100083, China Key Lab of Drilling and Exploitation Technology in Complex Conditions, Jilin University, Changchun Jilin 130026, China)

机构地区：[1]中国地质大学〈北京〉工程技术学院,北京100083 [2]国土资源部深部地质钻探技术重点实验室,北京100083 [3]国土资源部复杂条件钻采技术重点实验室,吉林长春130026

出　　处：《探矿工程（岩土钻掘工程）》2017年第3期1-9,共9页Exploration Engineering:Rock & Soil Drilling and Tunneling

基　　金：国家自然科学基金项目"考虑热松弛效应的纳米结构材料热弹耦合行为研究"(编号:11472249);"深孔高温硬岩中涡轮钻进粘滑振动及其抑制机理研究"(编号:41572360);中央高校基本业务费项目"热-力-化多场耦合作用下结晶岩力学特性表征及应用研究"(编号:2652015080);国家科技支撑项目"农用机井成井设备研制与开发"(编号:2015BAD20B02);国土资源部复杂条件钻采技术重点实验室开放课题"超深孔结晶岩地层热-力耦合井壁稳定研究"(编号:DET201617)

摘　　要：针对钻井工程常遇的层理性地层,以应力张量坐标转换关系和井孔应力集中方程为基础,引入弱面剪切滑动和岩体Mogi-Coulomb双强度准则,建立了分析层理性地层井壁稳定性的模型。对含层理弱面的典型油气储层中钻井的合理钻井液密度和安全钻井方向进行研究,结果表明:层理面的存在加剧了井壁围岩的破坏,且改变了围岩破坏的位置;水平井坍塌压力随着钻井方向变化而连续性变化,其在特定钻井方向取得最小坍塌压力;斜井取得最小坍塌压力的方位与层理面在空间中并不垂直,空间中关于主平面对称的斜井破裂压力相同;既可获得较大钻井液安全压力窗口又可取得较小坍塌压力的方向为优选钻井方向,在钻井液压力窗口变化大的倾向上钻井需严格控制钻井轨迹曲线。Bedding formations are often encountered in drilling operations. On the basis of the stress tensor coordinate transforming relation and the borehole stress concentration equation, both the weak-plane shear slip criterion and rock mass Mogi-Coulomb criterions are introduced to build an analysis model for borehole stability. Researches on the reasonable drill- ing fluid density and safe drilling direction in typical reservoirs show that the existence of bedding plane significantly aggra- vates the rock damage and changes the damage position on the borehole wall ; the collapse pressure of horizontal well contin- ually varies along with the changes of drilling direction, thus the minimum collapse pressure is obtained in a particular drill- ing direction; in the inclined borehole, the minimum collapse pressure direction acquired is not vertical to the bedding plane experimentally, while the symmetrical inclined boreholes about principal planes have the same fracture pressure in space; the optimum drilling direction is the one with both larger safe density window of drilling fluid and smaller collapse pressure, and the drilling trajectory curve should be controlled strictly in the azimuth where the density window of drilling fluid changes greatly.

关 键 词：层理 钻井液安全密度窗口 轨迹优化 井壁稳定性 模型 

分 类 号：P634.1[天文地球—地质矿产勘探]