LIFE ASSESSMENT OF POWER PLANT BOILER STEELS

Many components of power plant boiler are exposed to elevated temperatures, aggressive environment, creep, fatigue, and other damage mechanisms that can cause degradation, deformation or cracking of components. Thus, it is possible for the life expectancy to be reduced. Steamlines, heaters and superheaters often require life assessment after the boiler has been in operation. It is important to assess the condition of boiler components periodically and to estimate the remaining life to provide guidelines for replacement. A properly managed life assessment program can extend the life of boilers by many years, thus avoiding major capital expenditure for the utilities. Boiler and pressure vessel codes and standards provide methods and rules that can be used to evaluate remaining life