Failure Analysis of Type 304 Stainless Steel Tubes in an Energy Production Plant Heat Exchangers

This work includes results of studies and experiments conducted on heat exchanger (heater) tubes of an energy production unit to determine the causes of their fractures. Experiments indicated that the main mechanism of such tube fractures is the simultaneous presence of relatively high vibrational bending stresses and corrosive agents. It was shown that the role of a vibrational bending stress due to high velocity of input steam is very impressive. The important point in this study was the branching of corrosion fatigue cracks during their growth in presence of NaOH and chloride ions. The use of impingement plates and water chemistry control were the most appropriate methods to prevent such failures.