Analysis and Research on Diagnosis Methods of AFA 3G Fuel Assembly Leakage

Based on the design and manufacture characteristics of AFA 3G high performance fuel assembly, this paper analyzes the various factors that lead to leakage of the fuel assembly, which is mainly escape of radioactive products caused by failure of the fuel cladding tubes. Aiming at the fuel assembly leakage, this paper comparatively analyzes three main diagnosis methods, including radioactive activity calculation of fission products, sipping test and ultrasonic detection technique. At the same time, the detection results are analyzed and verified for on-site detection of ultrasonic device, finally this paper raises improvement analysis of ultrasonic detection technique so that facilitating research and implementation of fuel assembly leakage detection better in the future.