The influence of molten steel temperature on plug bricks is mainly reflected in the following aspects:

I. Erosion

High temperature erosion: When the temperature of molten steel is high, the plug brick will be more strongly eroded. Chemical components (such as sodium oxide) in high-temperature molten steel will melt and decompose at high temperature, eroding the surface of plug bricks and reducing their slag resistance.

Local erosion: when the temperature of molten steel is uneven, the local area of plug brick may be accelerated by excessive temperature, resulting in local loss of brick structure.

II. Thermal shock stability

Thermal shock damage: the impact of high-temperature molten steel will lead to a sharp change in the surface temperature of plug bricks, resulting in thermal stress. If the thermal stress exceeds the strength limit of the brick, it may lead to cracking or fracture of the brick.

Temperature gradient: If the temperature of molten steel changes too fast, a large temperature gradient will be formed inside the plug brick, which will further aggravate the thermal shock damage.

III. Service life

Service life in high temperature environment: high temperature molten steel will accelerate the wear and erosion of plug bricks and shorten their service life. For example, when casting high-temperature molten steel, the service life of ordinary clay plug bricks is usually 1-4 times.

Influence of material selection on service life: For high-temperature molten steel, the service life can be significantly improved by using plug bricks based on high alumina, zircon or silicon carbide.

IV. Influence of molten steel temperature on physical state of plug brick

Solidification of molten steel: when the temperature of molten steel is low, the molten steel on the surface of the plug brick is easy to solidify, which leads to the adhesion between the plug brick and the nozzle brick, and the plug rod cannot be opened normally, which affects the pouring.

Uneven temperature: if the plug brick is heated unevenly, it is easy to crack or even break during pouring, which will affect the normal pouring.

V. Optimization measures

Material optimization: For high-temperature molten steel, it is recommended to use plug bricks made of high alumina, zircon or silicon carbide, which have higher fire resistance and corrosion resistance.

Design optimization: optimizing the shape and structure of the plug brick, for example, changing the plug from parabolic shape to spherical shape, can reduce the direct erosion of molten steel on the plug.

Process optimization: control the uniformity of molten steel temperature, avoid excessive temperature fluctuation and reduce thermal shock damage.

In a word, the temperature of molten steel has a significant influence on the corrosion, thermal shock stability, service life and physical state of plug bricks. By optimizing the material, design and technology, the service life of plug brick can be effectively extended and its performance can be improved.