管道定向钻穿越河流施工风险控制

由于施工条件复杂，导向孔钻进、管道扩孔及回拖过程存在不可见性，定向钻穿越施工时经常出现冒浆、卡管、钻机故障等作业风险，一旦控制措施失当，会对整个工程施工产生较大的负面影响。结合某天然气管道定向钻穿越河流施工，讨论了影响定向钻施工的各种风险因素，并针对潜在的风险源，制定了详尽的风险控制措施，主要包括：优化施工工序，优选钻具组合，确定与其地质条件相适应的泥浆参数，严格进行钻进轨迹控向，采取卡管风险削减措施等，成功穿越了地下粗砂层，避免了钻机推拉力不足、抱管及大面积冒浆等现象的发生，保证了定向钻施工作业的顺利实施，为今后类似工程的施工提供了参考。（图1，表1，参6）

Risk control in directional drilling river-crossing construction of pipeline

Due to the complicated conditions of construction, the process of drilling of pilot bore, reaming and backtow remain invisible. When directional drilling crossing is under construction, the risks of mud spillover, pipe stuck, drilling failure often occur, and improper control measures will have major negative influence on the whole project construction. According to the directional drilling crossing river of a gas pipeline, all risk factors affecting directional drilling are discussed, and in view of potential risk sources, detailed risk control measures are established, mainly including optimization of construction procedure and drilling assembly, and determining mud parameters suitable for geological conditions, strict direction control of drilling trace and adopting measures to reduce pipe sticking. These measures have made a success in crossing underground coarse sand, avoiding the deficiency of push and pull force, pipe locking and large-scale of mud spillover and ensuring the smooth implementation of directional drilling construction work, which provides references to the future similar project construction. （1 Figure, 1 Table, 6 References）