Boiler Shutdown Research Articles

An overheat boiler tube failure

Failure analysis of an electric resistance welded carbon steel boiler tube demonstrated that the mechanism of failure was long-term overheat due to heavy internal scaling, followed by short-term overheat due to localized heating during boiler shutdown.

Mid-Wall Temperature in an Eroded Section of an Austenitic Superheater/Reheater Tube

Superheater and reheater tubes in a fossil-fuelled boiler are subjected to erosion and corrosion that cause the tubes to lose their thickness in a localized manner. To avoid unscheduled tube failures due to creep damage and hence prevent large financial loss because of boiler shutdown and tube repairs, it is important to estimate creep life of these tubes. Creep life is very sensitive to metal temperature. This paper describes the development of a nondimensional parameter coined TM1*. It is shown that TM1* can be used to estimate the mid-wall metal temperature in the eroded/corroded section of tube.

Estimation of metal temperature variations for scarred boiler tubes

Boiler tubes in a fossil-fuelled power station are subjected to erosion and corrosion that caused the tubes to become locally thinned or scarred. To avoid unscheduled tube failures and hence prevent large financial loss due to boiler shut-down and tube repairs, it is important to estimate boiler tube lives. Boiler tube lives are very sensitive to tube temperature. This paper describes the development of a non-dimensional parameter termed T ∗ . It is shown that T ∗ can be used to estimate the tube temperature variation in the scarred tube section. Also a method has been described for volume estimation and characterisation of a tube scar. This is important for more accurate tube life assessments.

Performance of Modern Steam-Generating Units

Abstract This paper is the final report on a study made of the performance of 250 large steam boilers over a period of three years. The results of the first year’s study were reported at the 1929 Annual Meeting of the A.S.M.E., and a summary of the full three-year period was presented at the 1931 Annual Meeting. The study was requested by the Central Station Power Committee of the Power Division. The primary object was to study boiler outages and their causes and the effect of such factors as severity of use, design, fuels, and methods of firing on boiler reliability, in the hope that a yardstick might be obtained by which the individual operator could measure the performance of his own units and predict the probable availability of new designs. The data obtained from each unit are presented, together with some comparisons of types and classes of unit. There also is a discussion of primary causes of boiler shutdown, which has not appeared in either of the previous papers.