How to Achieve High-Temperature Monitoring and Process Visualization During the Secondary Refining Stage of LF Furnaces

With the continuous advancement of automation and digitalization in the steel industry, in-furnace visualization technology has become one of the core components of modern steel plants.The infrared furnace monitoring system provided by HTEC-video enables real-time observation of high-temperature areas inside the ladle furnace, visualizing temperature distribution and process conditions. For steelmaking operators, this accurate data provides a reliable basis for operational decisions and is of great significance in ensuring product quality, production stability, and operational safety.

Why LF Furnaces Require Infrared Temperature Measurement

What is an LF Furnace?

Before understanding why infrared temperature measurement is needed, it is important to know what an LF furnace is. An LF furnace is a critical component in metallurgical processes and a core refining unit in steel production. It is typically positioned after the primary furnace (such as a converter or electric arc furnace) and before the continuous casting machine. Therefore, it is also referred to as a “ladle furnace” or “secondary refining unit.”

Key components of an LF furnace include:

l Furnace body (ladle itself): A steel vessel lined with refractory material. The bottom is equipped with porous bricks to blow inert gas (usually argon) for stirring. Three graphite electrodes generate a strong arc via a transformer to heat the molten steel, similar in principle to an electric arc furnace.

l Water-cooled furnace cover: Used during refining to seal the furnace, control dust, and improve the working environment.

Why Infrared Temperature Measurement is Needed

During the refining stage, the main tasks include temperature adjustment of molten steel, alloy addition, deoxidation, and slag formation.

Traditional alloy feeding methods often rely heavily on operator experience, without precise calculation or control. In addition, the chemical reactions inside the LF are highly complex, making temperature changes difficult to track.

For modern steel plants pursuing high precision and efficiency, this directly affects steel quality, production safety, and process stability.

Infrared temperature measurement systems provide a non-contact solution, enabling continuous and real-time monitoring of furnace conditions. When abnormal high-temperature areas occur, the system can trigger alarm functions and output relevant data. Operators can directly observe temperature distribution and operational status through monitoring screens.

Project Overview

HTEC-video recently installed and commissioned an infrared temperature monitoring system on an LF furnace at Jiangsu Longteng Special Steel Group. This project builds on prior successful collaboration between the two parties. HTEC-video had previously deployed a visible-light in-furnace monitoring system on one of Longteng’s ladles, providing steelmaking operators with more intuitive visualization of in-furnace conditions.

In this collaboration, the newly added RB-TemTV-M800 infrared monitoring system is designed specifically for high-temperature monitoring and process observation during the secondary refining stage.

System Features and Advantages

The HTEC-video infrared in-furnace monitoring system is designed for complex steel plant environments characterized by high temperature and dust. Its core advantages include:

lReal-time monitoring of high-temperature refining conditions:Continuous acquisition of critical in-furnace temperature data, with alarms and data output for abnormal conditions.

lEnhanced operational visualization: Intuitive presentation of in-furnace temperature and operational status.

lSupport for secondary refining process control: Optimization of molten steel temperature, alloy addition, and composition adjustments.

lImproved operational safety: Reduced risk from manual close-range observation.

lSupport for intelligent development:Provides a data foundation for digitalization and automation in the steel industry.

Ongoing Collaboration and Future Potential

HTEC-video is committed to providing reliable high-temperature in-furnace monitoring solutions for the steel industry. The successful deployment of the infrared monitoring system at Longteng Special Steel marks a deepening of collaboration in high-temperature industrial monitoring and demonstrates the broad application potential of infrared in-furnace monitoring technology across different steel production processes.

The HTEC-video infrared in-furnace monitoring system delivers stable, clear imaging and temperature measurement in complex high-temperature environments, providing reliable data support for refining operations, enhancing production safety, and enabling intelligent upgrades.