Failura Analysis Project: Case Analysis
PV329
Planningemail4.docx
I hope your day is going well. I wanted to explain my failure analysis case study. I have chosen to talk about the failure of 321 stainless steel heater tubes in heavy crude oil. I will present an interesting finding; namely the occurrence of chloride stress corrosion cracking catalyzed by the presence of sulphur-bearing species where the precipitation of salts and coke from the heavy crude led to sensitization of the internal surface layer and sulphidation of the crack walls. A common type of failure within Industrial and Systems Engineering might focus on its errors within the planning or design of an established process, whether manufacturing or business process, but usually dealing with effects concerning a decreased efficiency and increased cost of the process or product. As Engineers, we also have a duty to look for ways to improve the problems of today. For this reason, I will talk about factors most affecting corrosion of stabilized austenitic stainless steels (SSs) in the refinery industry such as chloride and hydrogen sulphide, and I will give a brief background of circumferential crack failure observations with experimental details such as visual, measurenment and microscopic examinations as well as the implementation and explanation of the Electrochemical Reactivation (EPR) technique. Additionally, I will give results that will explain what the last observations, Microhardness Measurements, analysis of black deposits and solutions (including EPR results) are.
I will also complement my report with tables stating the Microhardness Measurements results. Furthermore, I will add figures that refer to EPR curves obtained for the service exposed with the solution, as well as figures related to a stainless steel heater tube and its microscopic examinations such as optical micrographs of a crosssection cut at the crack location; as-received tube section; circumferential crack seen after removal of studs; deposited black layer on internal surface; and stud portion of tube. All these figures are useful to find out what the problem is and which possible solutions or preventions to take.
Finally, The sources I will be citing in IEEE format are the following:
M.I. Abdulsalam and T. Shinohara, “Technical note: crevice corrosion of stainless steel in hot salt water,” April 2003. [Online]. Available: https://corrosionjournal.org/doi/10.5006/1.3277561. [Accessed: 17-Feb-2019].
H.M. Shalaby, K. Ravindranath, N. Tanoli and B. Al-Wakaa, “Failure of 321 stainless steel heater tube in heavy crude oil,” Case Studies in Engineering Failure Analysis, vol. 9, pages 1-8, 20 May 2017. [Abstract]. Available: https://www.sciencedirect.com/science/article/pii/S2213290217300238#bbib0040. [Accessed: 17-Feb-2019].
R.W. Bosch, “Electrochemical impedance spectroscopy for the detection of stress corrosion cracks in aqueous corrosion systems at ambient and high temperature,” Corrosion Science, vol. 47, pages 125-143, January 2005. [Abstract]. Available: https://www.sciencedirect.com/science/article/pii/S0010938X04001313. [Accessed: 17-Feb-2019].
Any recommendation you could give would be deeply appreciated. I look forward to reading your reply and thank you in advance for your time and consideration.
Best Regards,
Paola Vilela
Industrial and Systems Engineer
305-299-1826
Gainesville, FL
