Welcome
This is the website designed as a summation of a report submitted by Callum O'Dwyer as part of the Bachelors of Engineering programme at the University of Edinburgh, conducted with supervision by Dr Graeme Lee.
The report used the techniques available in the University to examine and evaluate plain carbon steels which have been unusually heat treated due to a fire. The study uses a fire in an oil refinery as a case study, the basis of which can be found in the Background section of the website.
The theoretical and literature basis of the report is found in various sections in Theory. The experimental method undertaken is found in detail in Methodology. The Results and Discussion section explores the findings of the report, along with the Conclusions.
If you have any questions, or if you would like to get in touch - my details can be found in the Contact page.
Introduction
This project aims to explore the metallography of two plain carbon steels that have been heat-treated to simulate fire damaged materials. Fire damage plus the cooling produced by fire hoses frequently produces abnormal microstructures that would not otherwise be encountered.
Refinery fires frequently damage the steels of pressure vessels and other components. The refinery management then have to decide their next course of action – is the plant subject to complete replacement, or can a metallurgical analysis be made with a view to reusing some of the plant? Albeit at a short period at reduced operating conditions.
The objectives of this project are as following:
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Emulate certain conditions that structural steels experience in fires.
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Explore the formation of unusual steel microstructures induced by high temperatures and rapid cooling.
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Conduct experimentation to ascertain additional properties of the affected steels.
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Use the acquired knowledge to predict the conditions the materials can withstand.
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Establish a method of treating and analysing steel specimens for the benefit of teaching and future research.
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Resurrect the accessibility and use of impact testing machines for metallographic analysis in the University.
The project primarily focused on the aftermath of a fire, looking at two extremes of cooling - a slow cool (on average, cooling 40K/hour) and a rapid quench (placing the steel in iced brine). This gives a range of steel microstructure in response to either extreme - whether the steel is left to slow cool in a hot enviroment, or is quenched using firefighters' hoses in trying to fight the fire.
Additionally, the project looked at steels with differing carbon contents, and the effect that maximum temperature has on the steel. More information about this can be found in Methodology - Parameters.
The report conclusions can be found here.
“The finest steel has to go through the hottest fire.”
Richard M Nixon