空气/泡沫钻井技术在高陡构造带凉东003-2井的应用

Air/Foam Drilling Fluid Technology in High Steep Tectonic Zone in Well Liangdong 003-2

凉东003-2井是位于川东北高陡构造带的1口滚动勘探开发井。该井二开采用了空气/泡沫钻井技术,总进尺为767.50 m,纯钻时为116 h,平均机械钻速为6.62 m/h,起到了加快钻井进度及防漏的作用。由于二开井眼较大,井较深,钻进中出水量大,为了满足携岩要求需较高压力,从而导致浅层地表岩石的裂缝、大鼠洞、方井、地表发生窜漏;并且由于地层产水量大,接单根时井底沉砂严重。介绍了该井在二开井段钻遇的井下复杂情况及其处理措施。

Well Liangdong 003-2,an exploration well,is located in the northeast Sichuan.Air/foam mud was used in the second section of the well in an effort to avoid mud losses.116 hours were used to drill 767.50 m in the second section,with an average speed of 6.62 m/h.The second section,with a relatively bigger size,was deep and a higher pump pressure was required for cutting suspension,thus induced fractures in the shallow formations were generated.Mud channeling and loss occurred.The settlement of sand in the mud during drill pipe connection was frequently occurred.This paper introduced the downhole troubles in the second section and the methods of solving them.