| 摘要 |
PURPOSE:To enable safe detection of leak caused by cracks and the like by sealing temporarily each jetting nozzle in the pressure container of a nuclear reactor, discharging water in the water-supply sparger, the thermal sleeve and a water-supply pipe and feeding the water-supply pipe with pressurized gaseous body under the condition that the jetting nozzles are dipped in water. CONSTITUTION:At the time of routine inspection of the pressure container 1 of a boiling-water reactor, the water inside the pressure container 1 is reduced and the water-supply sparger 8 is exposed. A nozzle closing device 10 is lowered by a rope 21 and fitted to a prescribed position, whereby each jetting nozzle 9 is closed temporarily. Next, after the water in the water-supply sparger 8, the thermal sleeve 7 and the water-supply pipe 2 is discharged by opening a switching valve 4 and a drain valve 6, the drain valve 6 is closed. Meanwhile, water is supplied into the pressure container 1 until the jetting nozzles 9 are dipped in water, pressurized air is sent to the water-supply pipe 2 by opening of a switching valve 3, and the leak caused by cracks and the like is detected by generation of air bubbles and by means of a pressure gage, etc. By this method, the leak can be detected safely. |
