| 摘要 |
PURPOSE:To search a leaking point by forcibly discharging staying vapor in the condition that plural holes formed near by a gas pipe are being sealed, and detecting the density of gas in after some time. CONSTITUTION:Centering a point where leakage of gas is found out, a plural number of vertical holes 2a, 2b... is formed in the axis direction of a buried gas pipe 1. The initial density of the gas is measured and recorded by inserting a gas detector 3 in each vertical hole. Then, a perforated pipe 4 is inserted into the vertical holes in order initiating at the hole 2a where leakage is found out, and the entrance port is blocked with a sealing material 5 to seal each hole, the vacuum pump connected with the pipe 4 is operated to discharge forcibly the vapor containing the leaked gas which is staying or dispersed in its surrounding ground for a specified period. Afterwards, when certain time has passed, the density of the gas is measured and recorded again at the equal time intervals for several times in each vertical hole, and the grade of density till it returns to the initially measured density is aquired, then the point were the grade of density is the largest is decided as the leaking point. |
