Simulation-Based Characterization of Tube-Cap Resistance Butt Welding of Nuclear Fuel for Light Water Reactors and Development of Melted-Volume Prediction Models

The most important process in the manufacture of light-water reactor nuclear fuel rods is tube-cap welding, which serves to seal radioactive uranium materials. Tube-cap welding is a method commonly used in production by sealing various materials into tubes and caps, and is used in the manufacture of fuel rods in nuclear power plants. In this study, the simulation-based characterization of tube-cap welding was carried out to understand the underlying mechanisms that govern the welding process and to use a model that can predict the melted volume during the welding process. The simulation results were then used to analyze the effects of various welding parameters on the melted volume during welding process. To analyze the mechanism of welding phenomena in the tube-cap welding, various weld variables such as welding current, overlap length, and force were used. Those are the main variables in the tube-cap welding used in nuclear fuel rods manufacturing thought simulation. To predict the melted volume of the weld, a regression model and a neural network were used to predict the amount of melt using the process with the main process variables as input variables. The study quantitatively determined the effects of each welding variable on the melted volume and analyzed the correlation between two factors.