特殊地质条件下的大口径管道定向钻穿越施工技术

Construction Technology of Large Diameter Pipeline Crossing with Directional Drilling under Special Geological Condition

陕京二线输气管道定向钻穿越永定河工程的特点是,地层松散,含水量低,黏结性差, 定向钻穿越时易冒浆,不易成孔,砂层易形成沉砂包钻;加之穿越管径大,扩孔级数较多,对地层的冲击扰动较大,增加了塌孔的可能性,施工难度很大。针对这些情况采取了多种措施,保证了穿越一次成功。文章介绍了这次施工中出现的问题及其应对措施,总结了特殊地质条件下大口径管道定向钻穿越施工的体会。

The characteristics of Yongding River crossing project with directional drilling in the second Shan-Jing gas pipeline are of loose stratum, low water content and poor adherence of soil, being prone to mud oozing and difficult bore formation, drill wrapped with soil in sand layer. In addition, because of the large pipe diameter, more bore expanding levels are needed, and it interferes with stratum by impact. Aimed at the difficult conditions, some countermeasures were adopted to guarantee the successful crossing in the first operation. This paper introduces the problems occurred in this construction and the countermeasure taken, and summarizes the constructional experience of large diameter pipeline crossing with directional drilling under special geological condition.