水平井环形防喷器压井法及应用

On Horizontal Well Annular Preventer Kill Method and Its Application

钻井现场发生溢流后,常采用加重钻井液的方法压井,但钻井液中还是存在严重的油气侵入现象,特别是裂缝性地层,常出现越加重钻井液而钻井液中的油气越多的现象,难以把井压稳。为了解决此类问题,在分析水平井溢流和传统压井井控技术特点的基础上,提出了水平井环形防喷器压井法。环形防喷器具有结构简单可靠,锥形胶芯结构-胶芯不易翻胶、寿命可测的特点,但要在不含硫化氢,裂缝、孔洞发育,钻头在水平段油气层,以及套压≤7 MPa的条件下使用。其操作要点为:确定关井油压,把钻头起到油气层顶部;关闭半封闸板防喷器,打开环形防喷器,排溢流。将该方法应用于江汉油田王平1井,应用效果较好。

Weighted drilling fluid is frequently used to kill the well to stop overflow in drilling site. However, oil and gas will intrude into the drilling fluid. Especially for fractured formation, the more weighted the drilling fluid is, the more oil and gas there is in the drilling fluid, making killing well hard. Through analyzing the characteristics of hori- zontal well overflow and traditional kill well control technology, this paper presents horizontal well annular preventer kill method. The annular preventer is simple and reliable in its structure and its service life can be measured. Its op- erating points are as follows., making sure shut--in pressure and tripping drill bit up to the top of hydrocarbon reser- voir, and dosing half--ram blowout preventer and opening annular preventer to discharge the overflow. Its applica- tion in Wangping--1 well of Jianghan Oilfield has achieved a good result.