Failure Analysis on Perforation of Tube Panel of Cement Kiln Waste Heat Boiler

Perforation leakage accident had happened three times after the tube panel of cement kiln waste heat boiler was put into performance for about two months, and means such as chemical compositions analysis, mechanical property test, macro inspection and scanning electronic microscope observation, were used to analyzed the perforation reasons. The results show that the main reason for the perforation was cavitation erosion happening at the tube panel elbow and caused by non-smooth circulation of local working medium in the middle evaporator. And then washout corrosion and oxygen corrosion were caused by the cavitation erosion, and they acted together and resulted in continuous thinning of the tube panel and final perforation leakage failure.