Effect of Radial Expansion of Cr-Mo Steel Tubes on Their Corrosion Behavior in Sea Water
- 1 Mechanical Engineering Department, Petroleum Institute, Abu Dhabi, UAE
- 2 Chemistry Department, Petroleum Institute, Abu Dhabi, UAE
- 3 Mechanical Engineering Department, Petroleum Institute, Abu Dhabi, UAE
- 4 Metallurgical & Materials Engineering Department, Colorado School of Mines, Golden, USA
- 5 Mechanical Engineering Department, Petroleum Institute, Abu Dhabi, UAE
- 6 Mechanical Engineering Department, Petroleum Institute, Abu Dhabi, UAE
Abstract
This paper studies the effect of expansion ratio on the corrosion rate of the expanded tubes exposed to sea water as well as the microstructure changes caused by the expansion of Cr-Mo steel tubes to large permanent deformations. 2.25 Cr-1.0 Mo steel (schedule 40 and schedule 80) tubes were subjected to various expansion ratios of 10%, 15%, 20%, and 25% by pushing conical mandrels through them using a piston. The microstructure was also studied to determine the effect of the expansion on the grain structure of the material. Microscopic examination of the expanded tubes revealed that grains elongate along the direction of the hoop stress and this elongation increases with an increase of expansion ratio. Moreover, it was found that corrosion rate and hardness increase with an increase in expansion ratio.
- Z. Ahmad, “Principles of Corrosion Engineering and Corrosion Control,” Butterworth-Heinemann, Burlington, 2006, pp. 9-14. HUdoi:10.1016/B978-075065924-6/50003-9U
- C. A. Apostolopoulos and D. Michalopoulos, “The Impact of Corrosion on the Mechanical Behavior of Steel Undergoing Plastic Deformation,” Materials and Corrosion, Vol. 58, No. 1, 2007, pp. 5-12. HUdoi:10.1002/maco.200603978U
- C. A. Apostolopoulos and D. Michalopoulos, “Impact of Corrosion on Mass Loss, Fatigue and Hardness of BSt500s Steel,” Journal of Materials Engineering and Performance, Vol. 16, No. 1, 2007, pp. 63-67.
- E. M. Gutman, V. I. Storonskii, and G. V. Karpenko, “Corrosion of Deformed Boiler Steel in Flushing Solutions,” Fiziko-Khimicheskaya Mekhanika Materialov, Vol. 4, No. 3, 1968, pp. 324-329.
- A. C. Seibi, S. Al-Hiddabi and T. Pervez, “Structural Behavior of a Solid Tubular Under large Plastic Radial Expansion,” Journal of Energy Resources & Technology, Vol. 127, No. 4, 2005, pp. 323-326.
- D. A. Jones, “Principles and Prevention of Corrosion,” 2nd Edition, Prentice-Hall Inc., Upper Saddle River, 1996, p. 146.
- L. Yang, “Techniques for Corrosion Monitoring,” Wood-head Publishing Limited and CRC Press LLC, Cambridge, 2008, pp. 58-64.
- W. F. Hosford, “Materials Science: An Intermediate Text,” Cambridge University Press, New York, 2007, p. 1.
- M. A. Al-Anezi, G. S. Frankel and A. K. Agrawal, “Susceptibility of Conventional Pressure Vessel Steel to Hydrogen-Induced Cracking and Stress-Oriented Hydrogen-Induced Cracking in Hydrogen Sulfide-Containing Diglycolamine Solutions,” Corrosion, Vol. 55, No. 11, 1999, pp. 1101-1109.