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Title: Stress Assisted Corrosion in Boiler Tubes - Failure Analysis

Abstract

Stress assisted corrosion (SAC) of carbon steel boiler tubes is one of the major causes of waterside failure in industrial boilers. SAC is a major concern for kraft recovery boilers in the pulp and paper industry as any water leak into the furnace can cause a smelt-water explosion in the boiler. Failed carbon steel boiler tubes from different kraft recovery boilers were examined to understand the role of carbon steel microstructure on crack initiation and SAC crack morphology. A number of carbon steel tubes showed a deep decarburized layer on the inner surface (water-touched) and also an unusually large grain size at the inner tube surface. SAC cracks were found to initiate in these areas with large-graineddecarburized microstructure. Tubes without such microstructure were also found to have SAC cracks. It was found that the decarburization and large grained microstructure may facilitate initiation and growth but is not necessary for SAC of carbon steel boiler tubes.

Authors:
 [1];  [2];  [1];  [1]
  1. Georgia Institute of Technology
  2. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
930862
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Conference
Resource Relation:
Conference: Corrosion 2007, Nashville, TN, USA, 20070311, 20070315
Country of Publication:
United States
Language:
English
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; 36 MATERIALS SCIENCE; BOILERS; CARBON STEELS; CORROSION; DECARBURIZATION; EXPLOSIONS; FURNACES; GRAIN SIZE; MICROSTRUCTURE; MORPHOLOGY; PAPER INDUSTRY; WATER

Citation Formats

Singh, Preet M, Pawel, Steven J, Yang, Dong, and Mahmood, Jamshad. Stress Assisted Corrosion in Boiler Tubes - Failure Analysis. United States: N. p., 2007. Web.
Singh, Preet M, Pawel, Steven J, Yang, Dong, & Mahmood, Jamshad. Stress Assisted Corrosion in Boiler Tubes - Failure Analysis. United States.
Singh, Preet M, Pawel, Steven J, Yang, Dong, and Mahmood, Jamshad. Mon . "Stress Assisted Corrosion in Boiler Tubes - Failure Analysis". United States. doi:.
@article{osti_930862,
title = {Stress Assisted Corrosion in Boiler Tubes - Failure Analysis},
author = {Singh, Preet M and Pawel, Steven J and Yang, Dong and Mahmood, Jamshad},
abstractNote = {Stress assisted corrosion (SAC) of carbon steel boiler tubes is one of the major causes of waterside failure in industrial boilers. SAC is a major concern for kraft recovery boilers in the pulp and paper industry as any water leak into the furnace can cause a smelt-water explosion in the boiler. Failed carbon steel boiler tubes from different kraft recovery boilers were examined to understand the role of carbon steel microstructure on crack initiation and SAC crack morphology. A number of carbon steel tubes showed a deep decarburized layer on the inner surface (water-touched) and also an unusually large grain size at the inner tube surface. SAC cracks were found to initiate in these areas with large-graineddecarburized microstructure. Tubes without such microstructure were also found to have SAC cracks. It was found that the decarburization and large grained microstructure may facilitate initiation and growth but is not necessary for SAC of carbon steel boiler tubes.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

Conference:
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