Distributed Sapphire Fiber Bragg Gratings Based Thermal Profiling of Submerged Entry Nozzles

Journal Article · Tue Jul 29 00:00:00 EDT 2025 · IEEE Transactions on Instrumentation and Measurement

DOI:https://doi.org/10.1109/TIM.2025.3593567· OSTI ID:2574255

Mumtaz, Farhan ^[1]; Tekle, Hanok ^[1]; Zhang, Bohong ^[1]; Li, Xiaodong ^[2]; Abraham, Sunday ^[3]; Mathis, Bryant ^[4]; Smith, Jeffrey D. ^[1]; O’Malley, Ronald J. ^[1]; Huang, Jie ^[1]

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1. Missouri University of Science and Technology, Rolla, MO (United States)
2. Shinagawa Refractories Co., Ltd (Japan)
3. SSAB Iowa Inc., Muscatine, IA (United States)
4. SSAB Alabama Inc., Axis, Al (United States)

This research focuses on the application of sapphire fiber Bragg gratings (FBGs) for instrumentation in submerged entry nozzles (SEN) 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 laser technology into a one-meter-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 hours under extreme environmental conditions. The coupling between silica and sapphire fibers was investigated and implemented during sensor packaging. Here, the sensor successfully captured the pre-heat 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.

• Research Organization: Missouri University of Science and Technology, Rolla, MO (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Energy Efficiency Office. Advanced Materials & Manufacturing Technologies Office (AMMTO)
• Grant/Contract Number: EE0009119
• OSTI ID: 2574255
• Journal Information: IEEE Transactions on Instrumentation and Measurement, Journal Name: IEEE Transactions on Instrumentation and Measurement; ISSN 1557-9662; ISSN 0018-9456
• Publisher: IEEE
• Country of Publication: United States
• Language: English

Related Subjects

Sapphire Fiber Bragg Grating
Steel-making industry
Submerged entry nozzles
femto-second laser fabrication
highly multimode waveguide