Burst failure analysis of a convection tube

The failure causes of a burst convection tube used in heat recovery steam generator were analyzed by the chemical composition, optical microscope and scanning electron microscope analysis. The results show that the metallographic microstructure of the burst convection tube is ferrite and pearlite. Based on the scanning electron microscopy analysis, the thinning of the burst convection tube wall is caused by erosion. Ultimately, the convection tube bursts due to insufficient strength.