Converter Slag Stopping Vehicle: The "Precision Gatekeeper" in Iron and Steel Smelting

I. Core Mission: Why Is a Converter Slag Stopping Vehicle Needed?

• Molten steel contamination: Iron oxide in the slag consumes alloying elements (e.g., manganese, silicon, aluminum) in the molten steel, reducing alloy yield. At the same time, it causes fluctuations in molten steel composition, affecting the mechanical properties of steel products.

• Refining equipment damage: Slag entering the ladle may adhere to key components such as refining furnace electrodes and vacuum chamber walls, shortening equipment service life and increasing maintenance costs.

• Increased refining burden: If the slag volume exceeds the standard, additional slag-forming agents must be added for deslagging treatment, prolonging the refining cycle and raising production costs.

II. Working Principle: The Mechanical Logic of "Precision Timing"

• Standby stage: The slag stopping vehicle parks on the track beside the converter tapping hole. It receives real-time signals (such as converter tilt angle and tapping flow) through the control system and waits for the intervention command.

• Intervention stage: When 70%-80% of the molten steel has been tapped (molten steel is nearly exhausted, and slag begins to approach the tapping hole), the control system drives the slag stopping vehicle to move along the track toward the tapping hole. At the same time, it adjusts the angle and height of the slag stopping rod (or slag stopping ball).

• Slag stopping stage: The slag stopping rod (usually equipped with a high-temperature-resistant refractory head at the front end) is precisely inserted into the inner side of the converter tapping hole, forming an "interception barrier". At this point, since the density of molten slag is lower than that of molten steel (approximately 2.8g/cm³ vs. 7.8g/cm³), the slag is blocked inside the converter, while the remaining molten steel flows into the ladle through the gap between the slag stopping rod and the tapping hole.

• Reset stage: After tapping is completed and the slag is fully blocked, the slag stopping vehicle quickly retracts to the standby position. Meanwhile, the refractory head of the slag stopping rod is inspected or replaced in preparation for the next operation cycle.

III. Core Structure: The "Triple Guarantee" of Heat Resistance, Precision, and Stability

• Travel system: Composed of tracks, drive motors, reducers, and wheels, it adopts "frequency conversion speed regulation + servo control" technology to ensure the movement precision of the slag stopping vehicle meets the requirement of "accurate alignment with the tapping hole". The track surface is usually paved with high-temperature-resistant and wear-resistant steel plates to prevent deformation caused by high temperatures.

• Slag stopping actuator: The core component is a liftable and rotatable slag stopping rod. The rod body is made of high-strength heat-resistant steel, and the front end is equipped with aluminum-magnesium-carbon refractory bricks or corundum refractory castables. Some advanced slag stopping vehicles are also equipped with an "automatic rod replacement device", which can replace the refractory head without manual intervention.

• Hydraulic control system: Responsible for driving the lifting and rotation of the slag stopping rod, it uses high-temperature-resistant hydraulic oil (with an operating temperature up to 120℃) and seals. It is equipped with pressure sensors and flow control valves to ensure stable slag stopping actions and rapid response.

• Electrical control system: With a PLC (Programmable Logic Controller) as the core, it integrates a touchscreen operation interface, a remote communication module, and safety interlocking devices. It can display real-time parameters such as the slag stopping vehicle’s position, the angle of the slag stopping rod, and the pressure of the hydraulic system. Meanwhile, it links with the converter control system to realize "fully automatic slag stopping". In addition, it has a fault self-diagnosis function: in case of problems such as hydraulic oil leakage or motor overload, it can immediately shut down and trigger an alarm.

• Protection system: High-temperature-resistant heat insulation panels are installed on the outer side of the vehicle body to reduce the impact of high-temperature radiation on internal components. Key electrical components are equipped with dustproof and waterproof covers to adapt to the dusty environment of the converter workshop.

V. Future Trends: More Intelligent, Greener, and More Integrated