微流量精细控压钻井技术在冀东油田的研究与应用

RESEARCH AND APPLICATION OF MICRO-FLUX MPD TECHNOLOGY USED IN JIDONG OILFIELD

冀东油田南堡2号潜山储集层裂缝发育,地层压力系统复杂且具有高气油比的特点。欠平衡钻进过程中时常发生井漏、溢流和漏喷同存等复杂情况,钻井时效低,井控风险大。为解决这一技术难题,在NP23-P2012井奥陶系储层段开展了微流量精细控压钻井作业。通过井下环空微流量监测,地面节流设备自动调整回压及调整钻井参数等手段,实现了对井底压力的实时监测和精确控制;及时发现并快速控制了钻进过程中的溢流、漏失情况,避免了井下情况的进一步恶化,成功实现了"零密度"窗口条件下的安全钻进,极大地降低了井下复杂时间和井控风险,并使得水平段延伸能力大大提高;作业过程中共发现7个油气显示段。该项技术的成功应用为相似复杂地层控压钻进作业积累了经验。

At Nanpu 2,a huried-hill structure at Jidong oilfield,the reservoir formation has well-developed fractures,complicated formation pressure system and high oil-gas ratio,which often leads to lost circulation,overflow,or well-kicks during underbalance drilling,resulting in NPT increase and well control risk.For this,micro-flux MPD technology was applied to drill the Ordovician pavzone at Well NP23-P2012.By using the micro-flux monitoring system,automatic back pressure adjustment equipment and drilling parameters control/regulation,the balance between down-hole pressure and formation pressure under different conditions was achieved.The micro-flux MPD technology could rapidly detect and solve the borehole problems before it caused something serious,realizing safe drilling under zero density window,the NPT and well control risk largely reduced,and the horizontal interval largely extended.The successful application of this technology can provide certain reference for drilling operations in similar formations.