关键词: 煤层气, 可控水平井, 低成本, 二开井身结构, 半程固井

Abstract: In order to basically solve the previous problems of the open hole multilateral branched horizontal well, such as collapsing, clogging, having difficulties to dredge, operate and increase production, the theory of controllable horizontal well has been put forward, which is aiming to control the hole, reconstruct easily, operate fast and effectively, and be applied into reality widely, through the improvement of the structure of the second spud well with full bore, non-drilling half range cementing, the drilling fluid stabilization of less damage to the side-wall, drilling methods and completion technology. Meanwhile, whether the horizontal segment of the well is upward sloping or downward sloping, rod pump can be set into the well to drain directly without drilling drainage cavern well, which decrease the drilling investment to a large extent and has a positive effect on factory development of horizontal well groups. Huabei oilfield CBM area has promoted and tested more than 70 wells, guaranteed the drilling successfully rate to be 100%, decreased 45% of the total cost of drilling and draining, compared with open hole multilateral branched well, and increased the production in 1.89 times than open hole multilateral branched well. In conclusion, the Huabei oilfield CBM area has achieved the goals of low cost and effective development.