雾化空气钻井技术在普光气田的应用

Application of Misted Air Drilling to Puguang Gasfield

随着普光气田大规模成功应用空气钻井技术,其在机械钻速的提高、井斜控制等方面都取得了较大成效,但由于上部陆相地层存在水层,如果继续使用空气钻井会导致井下复杂及事故的发生,从而制约空气钻井技术的应用。如若过早转为钻井液钻井,由于地层具有倾角高和裂缝发育的特点,将导致机械钻速低、井斜不易控制、井斜过大、地层漏失严重等问题的出现。近两年在空气钻井的基础上通过使用雾化空气钻井技术解决了这些难题,并在应用中结合普光地区的地质构造特点采取了一些新的技术措施,取得了一些经验。

With a successful and large-scale application of air drilling to Puguang Gasfield, some achievements in both penetration-rate enhancement and well-deviation control have been made. Since aquifer exists in the upper terrigenous formation, it will result in downhole complexity and accident if continuing to use air drilling. But, if switching to use mud drilling too early, it will lead to problems such as low penetration rate, uneasy well-deviation control, large well deviation and serious circulation loss just because the formation is characterized by high dip and developed fracture. These difficulties have been solved in the last two years by misted air drilling. In this paper, combined with geological structure features of Puguang area, some new measures have been adopted and some experiences have been gained.