Metallurgy and Steelmaking

The metallurgical site environment is the "extreme test ground" of the instrumentation industry:high-temperature radiation, heavy dust, intense vibration, strong electromagnetic noise from cranes and variable frequency drivesall interwoven. The water systems, gas systems and hydraulic systems of the blast furnace, converter, continuous casting and rolling processes are intricate; a single spurious signal can cause a blast-off, a casting sequence interruption or even a rolling line shutdown.

Common challenges:Electromagnetic interference causes proximity switches and limit switches to malfunction, triggering equipment interlock shutdowns; key temperature measurement points such as rolling mill main motor bearings and continuous casting moulds are close to high-temperature radiation zones, making sensors prone to damage; the distance from the site to the electrical room is long, causing attenuation and crosstalk in long-distance analogue signal transmission; valve feedback signals in dedusting and gas systems fail due to moisture.

Our solution:Switch amplifiers provide interference suppression and wire-break detection, reliably converting on-site digital signals into relay or thyristor outputs; signal isolators and splitters perform centralised signal isolation and one-to-many distribution in the electrical room; temperature transmitters with high-temperature-resistant sheaths handle temperature measurement of rollers, bearings and secondary cooling water; surge protective devices protect outdoor and overhead lines; H system remote I/O is arranged nearby, shortening the distance from sensors to acquisition points.

Measured benefits are reflected inreduced false alarms and spurious trips, and maintenance changing from "troubleshooting along the line" to "diagnosis at the cabinet", with the operating rate of main equipment rising accordingly.

• Temperature monitoring for blast furnace body, hot blast stoves and gas systems
• Temperature control for continuous casting secondary cooling water, moulds and roller tables
• Temperature and vibration interlocking for rolling mill main motors and gearbox bearings
• Valve position feedback and belt misalignment switch signals for dust removal and gas systems