Trenchless technology given rised to the 20 centuries in abroad 70 ' s empress period , as an new construction technique in paving underground tube line . directional drilling come into being the most potential method because it achieve accuracy designed - area on trenchless technology , so it bring great benefit , especially in complexity pipe line area of city 非开挖铺设地下管线施工技术(简称非开挖铺管技术)是国外二十世纪七十年代后期发展起来的一项管道施工新技术,定向钻进非开挖铺管技术因其高精度的定位能力而成为非开挖四大工法之中最具潜力的技术,在城市管网极为复杂的地区,是其它施工方法难以代替的,社会经济效益尤为突出。