METHOD, INTRATUBE APPARATUS AND INJECTION UNIT FOR MARKING TRUNK PIPELINE WALL DEFECTS WITH RADIOACTIVE TRACER SUBSTANCE Russian patent published in 2002 - IPC

FIELD: gas transportation engineering. SUBSTANCE: method involves transporting radioactive gas tracer along the main in reservoir under pressure that is lower than gas transportation pressure. Just before its being introduced into technological chamber, gas from the technological chamber is supplied into the reservoir containing the radioactive gas tracer, mixed in the reservoir with the radioactive gas tracer and pressure is equalized in the technological chamber and reservoir. The produced mixture is injected from the reservoir into the technological chamber. The system for marking gas with radioactive substance in the technological chamber is equipped with remote control mixer and injector units each of which has mixing chamber of variable volume filled with tracer substance and extruder unit for forcing tracer and transported gas mixture supply from working chamber into the technological chamber. Injector unit has remote control unit for fixing piston in start position, its filler- dispenser unit having the second cylindrical locking organ engageable with draining tube. Canals are produced in walls of the filler-dispenser nozzle and draining tube. The piston has double- sided rod with the first and the second locking organs being mounted on the ends, the organs separating working and driven chambers from the surrounding medium in start piston position. EFFECT: improved safety conditions when working with radioactive gaseous tracers. 12 cl, 6 dwg