水文钻孔的弯曲(孔斜)对于施工及成井都极为不利。因此,必须对可能发生孔斜的原因给予足够的重视,并采取有效措施予以防治。一、孔斜的原因 (一)地质条件方面的原因在软硬不均的松散层中钻进时,钻具常偏向软层方向(图1-a);而在基岩中钻进时,钻孔常沿裂隙(图1-b)、溶洞(图1-C)、在缓倾角软硬互层中向垂直于层面方向(图1-d)、高倾角软硬互层中之软层的层面(图1-e及表1实例)等等偏移而孔斜。 (二)设备安装方面的原因若机座地基软硬不均,且安装不平、不稳、不牢;回转钻机的天车、转盘、钻孔三者的中心线不在同一垂线上;冲击钻机的桅 Hydrological borehole bending (hole slanting) is extremely detrimental to construction and well completion. Therefore, we must pay enough attention to the possible cause of the hole deviation, and take effective measures to prevent and treat it. First, the reasons for the slope of the hole (a) the reasons for geological conditions When drilling in the loose layers of uneven soft and hard, drilling tools are often biased toward the direction of the soft layer (Figure 1-a); while drilling in the bedrock, Drill holes are often along the cracks (Fig. 1-b), caverns (Fig. 1-C), soft layers in soft and hard layers in soft and hard alternate layers, perpendicular to the layer direction (Fig. 1-d), and soft and hard layers in high dip angles. The layers (Figure 1-e and Table 1 examples) are skewed and skewed. (II) The reasons for the installation of the equipment If the base of the machine base is unevenly distributed, the installation is uneven, unstable, and unstable; the centerline of the crane, turntable and drill of the rotary drilling rig is not on the same vertical line; the impact rig桅