A device for hermeticity testing of irradiated fuel assemblies in pressurized water reactors

The device consists of a gamma radiation detector and a sampler fixed to a driving mechanism. The sampler is hermetically connected to the upper end of the measured fuel assembly in the reactor core. The other end of the sampler is connected to the inlet of a chamber in which an ultrasonic generators installed. The chamber exit is connected to the intake of a pump, the outlet of which is coupled through a flexible pipeline to a double-walled chamber where the gamma detector of semiconductor type is placed. The detector is connected to a multichannel analyser, and the outlet of the double-walled chamber is connected to the coolant treatment system. The device, compared to other existing ones, has an improved reliability and shorter measurement time, and permits detection of microcracks in the cladding