Life Assessment And Fault Diagnosis Of Boiler Tubes In Power Plant

Safe and economic operation on utility boiler is an important part of safe production in power plants. Water-cooled wall, superheater, reheater and economizer are the main component of boiler heating surface. The tube explosion is the main types of boiler accidents. Reasonable life assessment and fault diagnosis can prevent or reduce the occurrence of boiler accidents and improve the safety and economy of power plant operation.The failure mechanism of tubes is investigated. The main failure mode and position are analyzed to improve the focalization of prevention for tube bursting and leakage based on the work environment and characteristics of the boiler tubes.The life loss model of boiler tubes is studied and the effect of thermal stress, the tube wall temperature, fly ash abrasion and corrosion on the life of the tubes. Researching on the relationship between the material aging and life loss, the models of life assessment are established based on the failure modes of boiler tubes and the influencing factors on the life.According to the principle of fault tree analysis, the fault trees of boiler tubes bursting and leakage are set up for qualitative and quantitative analysis. The main failure mode and induced factors are found, and some corresponding prevention and treatment measures are put forward in order to improve the reliability of the tubes.