汶川地震断裂带科学钻探Ⅱ号孔活动套管环隙充填液的研究与应用

Research and application of the filling fluids in the active casing annulus of Hole Ⅱ of the Wenchuan earthquake fault scientific drilling project

汶川地震断裂带科学钻探Ⅱ号孔(WFSD-2)由于设计变更,需要在311 m以上孔段下入活动套管并在其环隙灌注充填液。通过模拟实验,主要对3种充填液的黏滞特性进行了研究,计算确定了其相应状态下的黏滞系数,最终确定以2%浓度的水解聚丙烯酰胺(PHP)溶液作为活动套管环隙填充液。

As the design of Hole Ⅱ of the Wenchuan earthquake fault scientific drilling project changes,it is required to down an active casing into the hole from 0 to 311 meters and to fill some fluids into the annulus.Through simulation experiments,the viscious properties of three filling fluids are studied,and their viscosities under the corresponding state is calculated and determined.Finally,the concentration of 2% hydrolytic polyacrylamide（PHP） solution it determined as the filling fluid in the active casing annulus.