控压钻井技术在涪陵页岩气田的实践与认识

Practice and Cognition of Managed Pressure Drilling Technique in Fuling Shale Gas Field

摘要:

随着涪陵页岩气田勘探开发进程的不断深入，长水平段页岩气井在钻井过程中遇到的复杂事故愈发凸显。目的层龙马溪组，裂缝发育、岩性构成复杂且破碎严重，钻井中钻井液密度窗口窄，易发生垮塌、溢漏同存、水平井段漏失大量油基泥浆等问题。为了快速、安全有效地钻穿复杂页岩层段，采用控压钻井技术破解长水平段页岩气井井漏的钻井难题，在焦页33-4HF井应用控压钻井技术，在长水平段钻遇多个不同压力系数的漏失显示层，安全钻达完钻井深，大大减少了油基泥浆的漏失及其不良影响，减小了经济损失，取得了显著应用效果。

Abstract:

With the development of Fuling shale gas exploration and development, the complex accidents become more prominent during long horizontal well drilling process. In Longmaxi formation, fracture developed, lithology was complex with serious breaking; mud density window was narrow, so it was prone to collapse with overflow and leakage and the lost circulation of oil-based mud was serious in the horizontal wells section. In order to quickly and safely drill through the complex shale layer, MPD technique（managed pressure drilling）was applied in Fuling shale gas field. MPD technique was used in Jiaoye well 33-4HF, some leakage loss display layers with different pressure coefficients were drilled in the long horizontal section, the final depth was reached successfully, the leakage of oil-based mud and the adverse effects were greatly reduced; as a result, economic loss was also reduced with distinct application effects.