Abstract
Zirconium alloy is the main structural material used in the nuclear fuel production. This material has distinct advantages like less thermal neutron absorption cross-section and better chemical and mechanical properties for the reactor-working conditions. This material is widely used in boiling water and heavy water type reactors. Natural Uranium Dioxide (UO2) pellets are loaded into thin wall zirconium alloy tubes and ends are hermitically sealed by welding zirconium alloy plugs using resistance welding under helium atmosphere.
Industrial experimentation is carried out for this welding process and the responses are measured in the form of weld deformation (upset), ultrasonic testing, and metallographic tests. The collected data is statistically analyzed for determining the optimum weld parameters. The impact of variation in the set values of process parameters on weld quality is studied by sensitivity analysis using simulation on the response models developed. Accordingly these values are set as operational control limits and a weld acceptance criterion is developed as an input for Data Acquisition System (DAS) for online monitoring of welding process at a sampling rate of 20 K per sec.
ACKNOWLEDGMENTS
Authors are thankful to Mr. A. Rameswar Rao, GM, Mr. G. V. S. Hemantha Rao, DCE(F) for their valuable guidance in the experimental work and in the preparation of manuscript. Our sincere thanks to Mr. R. N. Jaya Raj, CE, NFC for according permission for the publication in the journal. The authors would also like to thank the reviewers of the manuscript and the editors of the journal for their valuable comments that have helped enrich the contents of this article.