DEVICE FOR REPLACEMENT OF UNDERGROUND PIPE LINES WITHOUT DIGGING-OUT TRENCHES Russian patent published in 1998 - IPC

FIELD: replacement of underground pipe lines. SUBSTANCE: device for replacement of underground pipe lines without digging-out the trenches includes striking mechanism, pipe breaking member, expander and tension rope secured on striking mechanism. Pipe breaking mechanism provided with knife is freely fitted on tension rope and is engageable with head portion of striking mechanism. Expander located on striking mechanism forces fragments of broken pipe line being replaced into group forming hole whose diameter exceeds diameter of pipe line being replaced. Then new pipe is connected with expander and drawn into thus formed. EFFECT: enhanced reliability and extended range of technological capabilities. 13 cl, 7 dwg