METHOD OF TRENCHLESS LAYING OF CASES UNDER AUTOMOBILE AND RAILWAY ROADS IN ERECTING MAIN PIPE LINES Russian patent published in 2003 - IPC

FIELD: construction engineering; erection of pipe lines under obstacles. SUBSTANCE: proposed method includes preparation of working and receiving trenches and thorough leveling of trench bottom. Then guide frame is laid and case with taper end-piece is placed on it; diameter of said end-piece exceeds diameter of pipe line. Pipe whose diameter is lesser than diameter of case by 10-30 times is forced into ground first; in the course of piercing ground, new pipe is welded till end of first pipe gets in receiving trench. Pipe which pierces the ground is filled with explosive and metal shields are laid external side of road where case is mounted. If necessary, metal shields are loaded and extended explosive charge is exploded and case is forced into channel thus formed. EFFECT: improved quality of trench for case; possibility of making trenches of any diameter.