Advertisement

Journal of Failure Analysis and Prevention

, Volume 10, Issue 6, pp 480–485 | Cite as

Failure Analysis of Cracked Reducer Flange

  • Khaled Habib
Case History---Peer-Reviewed

Abstract

A cracked reducer flange was analyzed for the cause of the failure. The flange was carefully cut to obtain samples for metallographic, X-ray, and scanning electron microscopy (SEM) Examinations. The examinations revealed that the introduction of chloride ions in the operational service led to pitting corrosion in the inner surface of the flange. Chloride ion inclusions were probably the result of chemical contaminations, i.e., cleaning chemicals’ contamination during shutdown of the operation. The introduction of corrosion pits caused unexpected load stress intensification and cracking of the flange. Consequently, stress corrosion cracking emanated from the pits under the influence of chloride attack and operational pressure. Then the cracks propagated in a transgranular manner, in the radial direction of the flange, until the final failure occurred.

Keywords

Reducer flange Pitting corrosion Stress corrosion cracking Metallographic examination X-ray Scanning electron microscopy Fracture roughness Stress intensity factor 

References

  1. 1.
    American Society for Metals (ASM): Metals Handbook, Properties and Selection, Iron, Steel, and High Performance Alloys, vol. 1, 10th edn, pp. 843, 856. American Society for Metals, Materials Park, OH (1990)Google Scholar
  2. 2.
    American Society for Metals (ASM): ASM Standards in Building Codes, vol. 1,A1-B210 M, 13th edn, p. 508. American Society for Metals, Materials Park, OH (1993)Google Scholar
  3. 3.
    Uhlig, H.: Corrosion and Corrosion Control, 3rd edn, p. 36. John Wiley & Sons Inc., New york (1971)Google Scholar
  4. 4.
    American Society for Metals (ASM): Case Histories in Failure Analysis, p. 366. American Society for Metals, Materials Park, OH (1979)Google Scholar
  5. 5.
    Shigley, J.W.: Mechanical Engineering Design, 3rd edn, pp. 28, 60, 169. McGraw-Hill, New York (1977)Google Scholar
  6. 6.
    Murakami, Y.: Stress Intensity Factors Handbook, vol. 1, p. 307. Pergamon, Oxford (1987)Google Scholar

Copyright information

© ASM International 2010

Authors and Affiliations

  1. 1.Materials Science Lab, Department of Advanced SystemsKISRSafatKuwait

Personalised recommendations