Research on Technology of Borehole Wall Protection and Leaking Stoppage in Complex Formation Drilling of Water Conservancy Project

There are big differences between drilling technology in water conservancy project and other engineering, especially, in borehole wall stability and stopping leaking technology, water conservancy engineering drilling process has its particularity. In this paper, classification method of complex stratum, its leaking stoppage and slurry requirements was presented, taking the borehole ZK21 of Zhuchanghe Reservoir as analysis example, complex formation borehole ZK21 is mainly weak interlayer which unsteady borehole wall and dropout phenomenon exist during drilling construction, aiming at the complex formation, the technical measures of borehole wall protection and leaking stoppage were proposed.