论文部分内容阅读
在复杂岩层钻进，平衡地层压力，保持孔壁稳定，是整个钻孔施工过程中的关键。我队在某铁矿区施工的地层，上部为第三、四系粘土、亚粘土、姜石、砂砾岩、亚砂土、流砂层等覆盖层，厚度为百余米到三、四百米。其中粘土层遇水膨胀易缩径；砂土层结构松散胶结性差，遇水后易剥落、坍塌；流砂层易垮孔，使钻孔严重超径。在这种部位发生钻杆断脱，给打捞带来了困难，为了钻进的
Drilling in complex rock strata, balancing formation pressure and keeping the hole wall stable are the key points in the entire drilling process. For the construction of a certain iron ore district, the upper strata of this team are the third and fourth series of clay, loam, ginger stone, conglomerate, sub-sand, sand and other overburden with a thickness of 100 to 300 and 400 meters . Among them, the clay layer expands easily with water expansion. The structure of the sand layer is loosely cemented and easily peel and collapse after encountering with water. Drill rod breakage occurred in this area, which brought difficulties in the salvage, in order to drill