Main causes of damage to steel ladle purging plug

Source: | Author:ChangXing Refractory | Published time: 1623 days ago | 940 Views | Share:

There are four main causes of damage to ladle purging plug as following,

During the use of steel ladle purging plug by steel manufacturers, the main reasons for the damage of purging plug are thermal stress, mechanical stress, mechanical wear and chemical erosion.

Air brick contains the core permeability and permeability block two parts, in the case of open bottom blowing gas, air permeability core working face will direct contact with high temperature molten steel, bottom blowing gas is cold air, and form a very high temperature difference between high temperature molten steel, with the increase of frequency, because of its thermal shock, air brick core by erosion, also easy to crack.

Vent brick package at the end of the working face, direct contact with high temperature molten steel temperature of working face is relatively low, the ladle in steel, casting steel, hot fix the recycling process, air brick and refractory material near the volume of the volume change due to temperature changes, due to the presence of temperature gradient and the metamorphic layer with its elements of different thermal expansion coefficient, from vent brick face to non-working surface volume change degree in the process of gradual change, it will produce shear force of air brick, the air brick in transverse cracks appear, severe cases can make air brick transverse fracture.

The high strength scouring of the bottom of the ladle by the molten steel during the process of steel production will accelerate the erosion of the purging plug. When the top surface of the plug is higher than the bottom of the plug, it will be subjected to shearing and scouring by the flow of molten steel. The part above the bottom of the plug will generally be washed away after one use. In addition, if the valve is closed quickly after refining, the reverse impact of the molten steel will also accelerate the erosion of the plug.

The working face of the plug is in contact with the steel slag and molten steel for a long time. The slag and molten steel contain iron oxide, ferrous oxide, manganese oxide, magnesium oxide, silicon oxide, etc., while the porous brick consists of alumina and silicon oxide, etc., which will react to form low melts (such as FeO·Al2O3, 2(MnO)·SiO2·Al2O3, etc.) and be washed away.