Study on Helium Leak Detecting for Post Irradiation Fuel Rods Available to Purchase

In this paper, many methods on testing for post irradiation fuel rods were introduced, especially the method which used helium mass spectrometer leak detector. Helium detection device including pressure helium device, sniffer probe of helium detection device and vacuum chase leaks of helium detection device were designed. First, the device which tested and verified during the mockup experiment had been verified effectively. Then, a series of helium detection experiments were carried out for post irradiation fuel rods in hot cell. The experiments which was divided into three stages; before cutting, leak detection was carried out with sniffer probe of helium and vacuum chase leaks of helium, the background approach to leak rate, which indicated that there was no leakage or helium had been completely escape. When cutting, greater pressure change caused by helium which released from fuel rods, The result showed that there was no leakage. After cutting, in the following helium detection experiment, the background still approach to leak rate, which also indicated that there was no leakage. All the experiments indicated that helium leakage device were effective in great extent, in short, helium leakage device and method were good useful for leakage detection in hot cell, helium leak detecting for post irradiation fuel rods became true.