水泥浆护壁堵漏的成功率目前仍只达到50～70%,其原因固然多方面,而水泥浆在孔内能否不被稀释,即替浆量是否适当,是其中极重要的一个方面. 准确的替浆量能使钻杆内外的流体(水及水泥浆)在静压平衡状态时(图1),达到同一高度(h_4=h_2,h_3=h_1),在提升钻杆的过程中,钻杆内外的水泥浆互相混 The success rate of cement slurry wall plugging is still only 50 to 70%. The reasons are many, and whether the slurry can be diluted in the hole, that is, whether the replacement of the slurry is appropriate, is one of the most important aspects. Accurate slurry replacement enables the fluid (water and cement slurry) inside and outside the drill pipe to reach the same height (h_4=h_2, h_3=h_1) in the static pressure equilibrium (Fig. 1). During the process of lifting the drill pipe, Drill pipe inside and outside the slurry mixed with each other