摘要
复杂地层取心和孔壁稳定一直是困扰地质钻探界的2大技术难题。以汶川地震科钻为例,5个钻孔都在断裂带上,地层极破碎、松软。针对部分孔段取心率低问题,设计一种新型阶梯式隔水底喷取心钻头,利用CFD技术对钻头孔底流场进行数值分析,优化钻头排水槽结构、泥浆性能和水力参数,寻找一种最佳组合,为提高岩心采取率、预防堵心,提高孔壁的稳定性奠定基础。
Coring and keeping the stability hole wall in complex formation are technical difficulties in geological drilling cir-cles.In Wenchuan Earthquake Fault Scientific Drilling (WFSD), 5 boreholes were in the fault zone and the formation was extremely broken and soft.A new type of stepped bottom jetting anti-erosion core bit was designed, numerical analysis was made on bottom flow field by CFD technology to optimize drainage groove structure, mud properties and hydraulic parame-ters in order to fine the best combination to lay foundations for core recovery rate improvement, core blockage prevention and higher hole wall stability.
出处
《探矿工程（岩土钻掘工程）》
2013年第7期107-110,共4页
Exploration Engineering:Rock & Soil Drilling and Tunneling
基金
科技部科技支撑计划专项"汶川地震断裂带科学钻探(WFSD)"项目之"科学钻探与科学测井"课题
中国地质调查局地质大调查项目"破碎和强缩径地层大直径深孔取心钻进技术研究"(1212011120258)
关键词
破碎松软地层
防冲蚀取心钻头
金刚石钻头
流场
数值模拟
结构优化
broken and soft formation
anti-erosion core bit
diamond bit
flow field numerical simulation
structure optimization
