气体钻井井眼净化程度判断方法探讨

Discussion on methods for determining hole cleaning degree in gas drilling

石建刚 陈一健 谢双喜

SHI Jiangang CHEN Yijian XIE Shuangxi

西南石油大学油气藏地质及开发工程国家重点实验室，四川成都　610500 中海石油基地集团采油技术服务公司，天津　300452

气体钻井是近年来发展起来的一种新的钻井方式，以其机械钻速快、防止井漏、保护储层等优点在全国范围内得到越来越多的应用。但由于气体钻井较雾化/泡沫钻井或常规钻井携岩能力最弱，井眼净化差。如果井眼不能得到有效的净化，气体钻井就不能快速的钻进。文中介绍了几种判断井眼净化程度的方法，即利用立压、排砂管压力、排砂管出口状态及排砂管线声音。通过现场应用发现，这些方法不仅能够及时地发现井眼净化不良，而且能够确定引起井眼净化不良的原因，为制定合理的处理措施提供了依据。

Gas drilling is a new drilling method which is developed in the past few years. It has been used more and more widely because it can enhance the ROP, prevent hole leakage, and protect reservoirs. However, air drilling is poor in carrying cuttings and cleaning boreholes as compared with the mist/foam drilling and conventional drilling. So air drilling will not be carried out fast if the borehole can not be cleaned effectively. In this paper, some methods to determine the hole cleaning degree are introduced, based on the standpipe pressure, the clearance pipe pressure, the state of clearance pipe outlet, and the voice of clearance pipe. Field application shows that these methods can non only be used to find out the problems in hole cleaning, but can be used to determine the causes of poor hole cleaning. They lay solid basis for developing reasonable treatment measures.