External and Internal Corrosion of Large-Diameter Cast Iron Mains
Publication: Journal of Infrastructure Systems
Volume 19, Issue 4
Abstract
Deterioration in cast iron mains manifests itself in the form of corrosion. External corrosion is typically found to occur in pipes buried in corrosive soils while internal corrosion is dependent on water chemistry and flow characteristics. In the literature, corrosion of cast iron pipes (external and internal) is typically characterized by corrosion pit depth even though corroded area and corroded pit volume as well as pit location may enhance this characterization. Knowledge of these corrosion pit properties permits the assessment of its structural integrity. Typically, internal and external corrosion pits and corroded areas are observed to occur in many irregular shapes and sizes, which make their characterization a challenge. This paper describes extreme value statistical models that can be used to estimate external and internal corrosion pit depths in cast iron pipes using indirect properties or parameters. The goal of these corrosion models is to be able to predict corrosion pit depth based on available data with an acceptable degree of confidence. The external corrosion model is calibrated using external corrosion data collected by Thames Water Utilities Ltd (TWUL) and subsequently validated with data obtained from the inspection of four cast iron pipe lengths. The internal corrosion model was calibrated using internal corrosion data but sufficient appropriate data was not available for its validation.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
This paper is based on a research project co-sponsored by the Thames Water Utilities Ltd., and the National Research Council of Canada (NRC). The authors of this study are indebted to Mr. Jeff Farrow, Mr. Nic Clay-Michael, Dr. Tim Evans, Ms. Rachel Cunningham, Mr. Vic Lee (retired from Thames Water Utilities Ltd.), and Dr. Hal Belmonte (formerly at Thames Water Utilities Ltd.), all of Thames Water Utilities Ltd. for providing documentation and clarifications during the course of this study.
References
Benjamin, J., and Cornell, A. (1970). Probability, statistics, and decision for civil engineers, McGraw-Hill, New York.
BS 78. (1917). “Cast iron pipes (vertically cast) for water, gas and sewage and special castings for use therewith.” British Standards Institution, London.
Farrow, J. (2010). Private communications, Thames Water Utilities Limited, Reading, England.
Federal Standard Stock Catalogue—WW-P-421. (1931). “Federal specification for pipe; water, cast-iron (bell and spigot).” U.S. Government, Washington, DC.
Hazen, A. (1911). “Of what thickness shall we make the walls of our large pipe lines?” J. New England Water Works Assoc., 25, 29–59.
Kleiner, Y. (2011). “Pipe condition assessment and renewal planning.” Chapter 11, Water loss reduction, Bentley Institute Press, Exton, PA.
Kleiner, Y., Rajani, B., and Krys, D. (2012). “Performance of ductile iron pipes. I: Characterization of external corrosion patterns.” J. Infrastruct. Syst., 108–119.
Kowaka, M. (1994). Introduction to life prediction of industrial plant materials: Application of the extreme value statistical method for corrosion analysis, Allerton Press, New York.
Laycock, P. J., Cottis, R. A., and Scarf, P. A. (1990). “Extrapolation of extreme pit depths in space and time.” J. Electrochem. Soc., 137(1), 64–69.
Mergelas, B., Bond, A., and Laven, K. (2006). “Financial benefits from seven years of water loss control utilizing the sahara system at Thames Water in the United Kingdom.” ASCE Proc. of the Pipeline Div. Specialty Conf., ASCE, Reston, VA.
Rajani, B., and Abdel-Akher, A. (2012). “Re-assessment of resistance of cast iron pipes subjected to vertical loads and internal pressure.” Eng. Struct., 45, 192–212.
Rajani, B., Kleiner, Y., and Krys, D. (2011). Long-term performance of ductile iron pipe, Water Research Foundation, Denver.
Rossum, J. R. (1969). “Prediction of pitting rates in ferrous metals from soil parameters.” J. Am. Water Works Assoc., 61(6), 305–310.
Royse, K. R., Tye, A. M., Linley, K. A., and Napier, H. J. (2009). The development of an underground asset management tool in BGS, British Geological Survey, Nottingham, England, 66.
Sægrov, S., König, A., Mattick, A., Milina, J., Röstum, J., and Selseth, I. (2003). “Methods for estimating water network rehabilitation needs.” Water Supply, 3(1–2), 63–69.
Schlick, W. J. (1940). Supporting strength of cast iron pipe for gas and water services, Iowa Engineering Experimental Station, Ames, IA.
Sheikh, A. K., Boah, J. K., and Younas, M. (1989). “Truncated extreme value model for pipeline reliability.” Reliab. Eng. Syst. Saf., 25(1), 1–14.
Stacy, H. A., and Fairchild, I. J. (1927). “Proposed United States government specification for centrifugally cast iron pipe.” J. Am. Water Works Assoc., 18(2), 208–218.
Thomson, J., and Wang, L. (2009). State of technology review report on condition assessment of ferrous water transmission and distribution systems, U.S. Environmental Protection Agency, Cincinnati, OH.
United States Pipe & Foundry Co. (1932). Handbook of de Lavaud cast iron pipe centrifugally cast, Burlington, NJ.
Wiggin, T. H., Enger, M. L., and Schlick, W. J. (1938). “A proposed new method for determining barrel thickness of cast iron pipe.” J. Am. Water Works Assoc., 31(5), 841–908.
Information & Authors
Information
Published In
Journal of Infrastructure Systems
Volume 19 • Issue 4 • December 2013
Pages: 486 - 495
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Mar 8, 2012
Accepted: Oct 24, 2012
Published online: Oct 26, 2012
Discussion open until: Mar 26, 2013
Published in print: Dec 1, 2013
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.