Experimental study on mechanical strength of fuel cladding tube under the loss of coolant accident

The objects of this experimental study are to verify the behavior of the fuel cladding tube under the loss of coolant accident and to correlate the above result with the mechanical properties of the tube materials. AISI 304L, 347 stainless steel and Zircaloy-2 were selected for test cladding materials. The study consists of four sections as follow: (1) Analysis of the loss of coolant accident for PWR and BWR, and the determination of the experimental conditions. (2) Tensile test of cladding materials at high temperature and at the various moderate load rates. (Test A) (3) High temperature burst test of the various size cladding tubes. (Test B) (4) Dynamic burst test realizing the condition of the loss of coolant accident. (Test C) It is concluded from a series of the above experiments that the strength of the cladding tube is scarcely affected with such a load rate as the pressure decreasing rate at the loss of coolant accident and it is possible to estimate the bursting pressure of the fuel cladding tube with the results of the tensile test to the materials. (author)