Causes of steel leakage between upper and lower slides of ladle sliding nozzle

February 22, 2019

The ladle sliding nozzle system includes upper and lower nozzle bricks and upper and lower sliding boards. The working principle of the sliding nozzle is to adjust the flow of molten steel by sliding the casting holes of the upper and lower slides by sliding machinery. Safe and reliable operation, saving refractory materials. However, in the ladle sliding nozzle system, steel leakage is likely to occur between the upper and lower slide plates. Generally due to the following reasons:

Causes of steel leakage between upper and lower slides of ladle sliding nozzle

(1) When carbon-containing slide is casting high-manganese, low-carbon, low-silicon steel, the concentration of oxidizing substances in the steel is high, and the carbon on the sliding surface of the molten steel is oxidized, resulting in a decrease in bulk density and surface strength of the refractory bricks, thereby the molten steel soaks the sliding plate surface, the skateboard surface was strongly eroded. During the process of pulling the skateboard, the surface molten steel and steel slag gradually increase. When the cold steel reaches a certain thickness, the gap between the slide plate will break out.

(2) The processing precision of the skateboard surface is low, the gap between the upper and lower slides exceeds the minimum gap of molten steel penetration, and the molten steel of the gap between the plates penetrates into the plate under the action of static pressure, causing the steel to be clamped, and the penetration of molten steel increases with the pouring time causes steel leakage.

(3) In the ladle sliding mechanism, the slide rails, the rail wheels and the shaft are worn seriously, and the mechanism reduction is reduced. Because mechanical spring decreases greatly due to the aging pressure, which leads to more pressure drop between the slides. When the pressure between the plates is lower than the static pressure of the molten steel, the steel leakage between the plates occurs.