Mechanical Property Evaluation and Remaining Life Assessment of Service - Exposed Steam Pipe of Boilers in : Thermal Power Plant

This paper is aimed at investigating the residual life
of more than eleven years service - exposed main steam
pipes of various boilers in a thermal power plant. The
remaining life assessment for safety were made using
destructive accelerated stress rupture and tensile tests
at different temperatures, and some nondestructive tests.
There was no evidence of localised damage in the form
of surface cracks, cavitation or dents in the service
exposed main steam pipes of all the boilers. So far as
the remaining life at 823 K is concerned, it is possible
to obtain a life of greater than 100000 hours, both at
the allowable as well as operating hoop stress levels of the service - exposed pipes, provided no localised damage
in the form of cracks or dents has been developed. It is
recommended that a health check should be carried out
after 50,000 hours of service exposure at 823 K.