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


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.


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


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Copyright information

© ASM International 2010

Authors and Affiliations

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

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