METHOD OF CLOSING PIPELINE FOR REPAIR Russian patent published in 2004 - IPC

FIELD: construction. SUBSTANCE: invention is designed for use at repairs on line part of pipeline with replacement of defective section. Two controllable closing devices are installed in pipeline. Said devices are moved, one after the other, by flow of pumped product and are provided with deceleration, stopping and sealing systems. Deceleration is performed with preliminary opening of bypass system. Closing devices are stopped at edge of deflective section with due account of pipe slope, are sealed and their bypass system is closed. Product is pumped out from section between closing devices into reservoir by means of external pump and part of defective section is cut out. Flanges of closing devices adjoining cut out section are furnished with subs which are connected with pump. Bypass system is opened, product is pumped from section between gate in pipeline and closing device, subs are removed, remaining part of defective section is cut out and section is replaced by new one. EFFECT: enlarged functional capabilities. 10 dwg