福建东西溪硬岩定向钻穿越施工

Pipeline Crossing Construction with Directional Drilling in Hard Rock Area of Dongxixi, Fujian

福建东西溪硬岩定向钻穿越施工,遇到的主要难题是入土点侧和出土点侧卵石层深约14～17m,穿越的大部分地层为花岗岩,长度约1500m。为此,在该穿越施工中采用了三项关键技术:超长距离夯套管技术、硬岩导向孔对接技术、硬岩扩孔技术。文章简要介绍了该穿越施工的过程及三项关键技术的应用情况。福建东西溪硬岩定向钻穿越成功,创造了国内硬岩定向钻穿越的最长纪录(1690m)。

In the pipeline crossing construction with directional drilling in Dongxixi, Fujian, the major challenge encountered is the thick pebble layer of 14～17 m on the both entering side and exiting side. The main stratum in the pipeline crossing area consists of granite with the length of 1 500 m. Therefore, three key techniques are adopted in this crossing construction, i.e. ramming casing in ultra long distance, pilot hole interconnecting in hard rock and reaming hole in hard rock. The crossing construction course and application of these key techniques are illustrated in this paper. This successful crossing project has created a domestic record of the longest distance crossing with directional drilling in hard rock.