Abstract
This article focuses on the application of sapphire fiber Bragg gratings (FBGs) for instrumentation in submerged entry nozzles (SENs) within the steelmaking industry. The SEN is pivotal for transferring molten steel from a tundish to a mold, while preventing the infiltration of oxygen and nitrogen from the surrounding environment. Maintaining optimal flow conditions in the mold is crucial for ensuring casting process stability and maintaining high-quality steel. Sapphire FBG sensors have been instrumented in SENs to enable distributed thermal mapping for monitoring the health of the SEN. The optical sensor comprises three cascaded sapphire FBGs inscribed using femtosecond (FS) laser technology into a 1-m-long sapphire crystalline fiber. The sensor underwent characterization in a laboratory setting up to 1600 °C and was tested for long-term stability over 40 h under extreme environmental conditions. The coupling between silica and sapphire fibers was investigated and implemented during sensor packaging. The sensor successfully captured the preheat sequence of the SEN in real-world steelmaking operations. Compared to conventional thermocouples, sapphire FBG sensors demonstrated exceptional efficiency and precision. They offer potential benefits such as increased productivity, reduced energy consumption, and minimized carbon footprint in the steel industry.
Recommended Citation
F. Mumtaz et al., "Distributed Sapphire Fiber Bragg Grating-Based Thermal Profiling of Submerged Entry Nozzles," IEEE Transactions on Instrumentation and Measurement, vol. 74, article no. 9530112, Institute of Electrical and Electronics Engineers, Jan 2025.
The definitive version is available at https://doi.org/10.1109/TIM.2025.3593567
Department(s)
Electrical and Computer Engineering
Second Department
Materials Science and Engineering
Keywords and Phrases
Femtosecond laser fabrication; highly multimode waveguide; sapphire fiber Bragg grating (FBG); steelmaking industry; submerged entry nozzles (SENs)
International Standard Serial Number (ISSN)
1557-9662; 0018-9456
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2025 Institute of Electrical and Electronics Engineers, All rights reserved.
Publication Date
01 Jan 2025
Comments
Office of Energy Efficiency and Renewable Energy, Grant DE-EE0009119