In modern steel plants, continuous casting is no longer just a link between steelmaking and rolling—it is the key factor that determines the capacity of the entire production line.
As new steelmaking systems set ambitious targets of over 10,000 tons of daily steel output, the continuous casting process must evolve from traditional “stable operation” to an integrated model defined by high speed, high quality, and long service life.
For large-scale systems producing more than 10,035 tons per day, stable casting speed and high equipment availability are critical to overall performance.
From Stable Casting to High-Speed Casting
Increasing casting speed brings clear productivity gains, but also higher technical challenges:
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A 0.1 m/min speed increase significantly raises demands on
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mold level stability
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uniform billet solidification
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mechanical precision of equipment
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Efficiency improvement is not just about faster machines—it also means reducing waiting time, minimizing temperature loss, and keeping the entire steelmaking–casting–rolling process synchronized.
Optimizing the Secondary Cooling System
The secondary cooling zone plays a decisive role in billet and slab solidification, especially at high casting speeds. Traditional experience-based water control is no longer sufficient.
1. Dynamic Cooling Control
A dynamic secondary cooling model was introduced based on:
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real-time casting speed
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steel grade superheat
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solidification end position
For wide slabs and special steels, a strong-to-weak cooling gradient is applied. This keeps slab surface temperature above 900°C in the straightening zone, effectively reducing transverse cracks.
2. Precision Nozzle Design and Monitoring
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High-precision atomizing nozzles ensure uniform water coverage
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Cooling uniformity is controlled within ±5%
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Online monitoring of water pressure, flow, and temperature enables rapid correction within seconds
Mold Flow Control at High Casting Speeds
The mold is the core of the continuous caster. At high speeds, molten steel flow must be carefully controlled to prevent defects and breakouts.
Key measures include:
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High-performance mold flux with low viscosity and strong lubrication
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Automatic mold level control (ALC) combined with electromagnetic braking (EMBr) to reduce flow impact
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High-frequency, small-amplitude mold oscillation to minimize oscillation marks and improve surface quality
Standardized Operation and Equipment Reliability
1. Standard Operating Procedures (SOPs)
Clear SOPs are implemented for four critical stages:
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start of casting
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strand connection
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ladle change
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end of casting
Molten steel superheat is strictly controlled within ±5°C, ensuring stable conditions throughout casting.
2. Long-Life Key Consumables (Procurement Focus)
Improving efficiency also depends on component lifespan:
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Submerged Entry Nozzles (SENs): high resistance to erosion and clogging
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Rollers and segments: hardfacing and thermal fatigue–resistant designs extend service cycles
This reduces downtime and supports long continuous casting sequences.
Toward “Zero Waiting Time” Across the Process
True efficiency comes from system-level coordination, not isolated optimization.
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Constant casting speed stabilizes converter and refining rhythms
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Intelligent scheduling reduces ladle waiting time by over 15%
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Optimized tundish control minimizes head and tail losses
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Overall metal yield increases by more than 0.5%
Conclusion
Stable high-speed continuous casting is the final step in fully releasing the capacity of a new steelmaking system.
Through:
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refined secondary cooling optimization
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precise mold flow control
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reliable refractory and equipment supply
the production ceiling of 10,035 tons per day was not only exceeded, but a data-driven, digital steelmaking governance system was also established.
For modern steel plants, high-speed continuous casting is no longer optional—it is a strategic capability for sustainable, high-efficiency production.
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