2024 Steel Intern Scholarships
Whalen J. Downs
I worked at Gerdau Special Steel North America in Fort Smith, Ark., USA, the summer of 2024. Originally founded as Macsteel, Gerdau acquired this bar mill in 2008. During my time with the company, I worked on a couple projects which allowed me to gain additional real-world experience and try things I hadn’t done before. My projects gave me the opportunity to interact with lab techs, operators, maintenance and furnace crews. I was able to learn a lot about challenges they face on the job as well as the skills needed and how what I worked on affected those around me. Following the necessary guidelines and procedures, I was able to complete the tasks assigned to me while learning as much as possible.
The main project I worked on involved working with the electric arc furnace injection system for both furnaces to improve the accuracy of lime injection and slag chemistry. Tracking lime usage can be problematic as the system would frequently time-out and record data inaccurately. Using an IBA Analyzer seemed to be the most accurate way to record usage during lime injection, which allowed me to continue with the project. Lime is used to form slag and can be measured through slag samples and chemistry analysis. Lime injection for slag is very important as it can protect the furnace refractory from wear, insulate the steel, remove impurities and protect the furnace during arcing. A lime calculator took the data we had acquired and provided recommended changes to the setpoints so that trials could begin. Slag samples taken with the new setpoints suggested improved chemistry but increased the lime consumption of furnace 4 at the mill. Old files provided some new setpoints for which slag samples suggested yielded similar results with a greater reduction in lime usage. I worked with the slag chemist, operators and furnace utilities to complete my tasks of acquiring samples, analyzing data, and improving the lime usage.
The second project I worked on involved examining the difference in N values recorded between the ARL and Leco machines in the chem lab. This involved working closely with the lab technicians to train on Leco analysis and understanding the differences in how the machines analyze metal. ARL Metal Analyzers are optical emission spectrometers that work through the application of a spark through an electrode and metal sample to vaporized atoms which are measured as intensity of light wavelength. Leco functions through combustion of a sample with a known mass material in the sample being converted to gaseous combustion products before being separated and quantified. Nitrogen is measured in Leco through thermal conductivity as each chemical has a separate thermal conductivity. It was found that, on average, the Leco reads N values 0.0002 lower than ARL analysis of the same samples. This is likely due to Leco Analysis measuring only a few chemicals while ARL measures a broader range, and light interference may affect the results. The low variability between ARL and Leco suggests that ARL analysis is accurate enough for quick chemical analysis of lollipop samples during plant production.
Overall, I had a great experience during my time at Gerdau, where I was able to learn a lot of applicable skills and apply those which I already knew. I understand the steelmaking process much better than I had before and gained invaluable skills, knowledge and experiences from everyone I encountered. I want to thank AIST for this scholarship, which allows me to continue my pursuit of knowledge, and Gerdau for giving me the opportunity to intern with them and learn more about steelmaking in an involved way.