绳索取心技术在深厚松散地层钻探中的应用研究OA

In the construction of core drilling engineering in deep and loose formations,problems such as low drilling efficiency,poor coring quality,frequent downhole accidents and high construction costs are commonly encountered.To solve the above problems,this paper optimized the assembly of wireline coring drilling tools and developed a set of coring technology suitable for deep-hole operations in loose formations.The optimized drilling tool combination includes 133 mm diameter wireline coring bit,127.5 mm diameter lower reamer,122 mm diameter wireline coring tool assembly,127.5 mm diameter upper reamer and 114 mm diameter wireline coring drilling rod.Through tests on drilling bits of different diameters and adjusting the annular clearance between hole wall and drilling tool,the stability of drill string and the smoothness of cuttings removal can be balanced;the problem of core erosion was solved with stepped bottom jetting bit,the problem of unreliable core locking can also be solved by integrating sintered core locking and spring core locking technologies,and the long-term stability of borehole wall in open-hole section was realized by correspondingly optimizing non-dispersed low-solid polymer flushing fluid system.Engineering practice has shown that this technology can significantly improve the mechanical drilling efficiency and core recovery rate,thereby effectively reducing the labor intensity of drilling operations.It can provide a systematic technical reference for coring drilling projects in similar deep and loose formations in China.