Precautions for use of anti-permeable air bricks for ladle

Out-of-furnace refining has become an important part of the modern steelmaking process, and argon blowing from the bottom of the ladle is also an important part of the out-of-furnace refining, and the ladle air-permeable brick is the key element to realize this process, and steel manufacturers are particularly concerned. A good air-permeable brick should have the characteristics of long service life, good bottom blowing effect, no (less) blowing, safe and reliable. The current breathable bricks mainly include slit type and impermeable type. The width and distribution of the slits of the slit type air-permeable bricks must be reasonably designed according to the capacity of the ladle, the smelting steel type and the required air permeability, so the production process is more complicated; Recently, a large number of irregularly distributed through pores are produced, and the production process is relatively simple.

The anti-permeable air brick for ladle adopts the structure of a combination of a gas-permeable inner core and dense high-strength materials: the working area of the brick core is an anti-seepage design, and the security device adopts a slit design. When a slit gas channel is observed, it indicates The residual height of the air-permeable brick is insufficient, and the air-permeable brick needs to be replaced.

Figure 1 Ladle breathable brick

In the process of transportation and installation of the breathable brick, make sure that the thread of the tail steel pipe is not damaged, so as to avoid loose pipe connection and air leakage, which will affect the argon blowing flow and blowing rate; ensure that the tail steel pipe does not enter dust and sundries, etc.; ensure that the breathable brick The working surface is not covered by fire mud or other materials to avoid unsuccessful bottom blowing. During installation or use, ensure that the pipeline is tightly connected and does not leak air, otherwise the argon pressure is insufficient, which will affect the stirring effect and cause the blow-through rate to drop.

When the converter is tapped, the alloy is added too early and the molten steel level in the ladle is too low, the low and strong permeability of the alloy melting point will easily lead to poor permeability of the brick core. In addition, the premature addition of alloying leads to a lower temperature at the bottom of the ladle; if the argon blowing operation is not standardized, and the large argon gas is not stirred in time after tapping, it is easy to cause it to be difficult to blow off in the early stage of refining.

Severe encrustation at the bottom of the ladle, many online turnover ladle, timely dumping of slag after the completion of steel pouring, hot repair without purging the ventilating brick, longer hot stop time of the ladle, low tapping temperature of molten steel, etc., will easily cause the surface of the brick core Residual molten steel and steel slag are easy to crust on the surface and affect air permeability.

Figure 2 Breathable bricks for aluminum smelting

As a professional manufacturer of refractory materials, our company has been developing, producing and selling anti-permeable air bricks for ladle for many years. The use of anti-permeable air bricks not only has a high safety factor, but also overcomes the shortcomings of a shorter life span than a slit breathable brick, and fundamentally promotes the steelmaking process.