BAG DEVICE TO BE USED FOR GAS CUTOFF AND CUTOFF CONSTRUCTION METHOD THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a bag device shortening working time, reducing cost and being used for gas cutoff and a cutoff construction method therefor. SOLUTION: Gas is cut off by introducing main bags 2 provided with nonflammable fibers 12 at rear parts toward an opposite side of a portion X to be repaired into a pipeline 3 from bag introduction holes 31, 32 of the pipeline 3 and introducing opposite bags 1 provided with nonflammable fibers 12 at front parts toward the portion X to be repaired into the pipeline 3.