High alumina refractory bri CK for hot blast stove refers to the refractory products made of high alumina clinker or sillimanite mixed with part of combined clay, with Al2O3 content not less than 48%. The hot blast stove is a huge brick structure built entirely by refractories, which provides the hot blast equipment for blast furnace smelting. The internal masonry is subjected to high temperature and its own load for a long time, and at the same time it is eroded by various oxide dust in the gas.
The hot blast stove is a huge brick structure built entirely by refractories, which provides the hot blast equipment for blast furnace smelting. The internal masonry is subjected to high temperature and its own load for a long time, and at the same time it is eroded by various oxide dust in the gas. Before the 1950s, the air supply temperature was 800 ℃ on average, and clay bricks and semi silica bricks were used for masonry. With the large-scale blast furnace volume, the hot blast furnace also expanded. In order to coordinate with the blast furnace to improve productivity and strengthen smelting operation, the air supply pressure and temperature continued to increase.
In the 1960s, the wind temperature rose to 1000 ℃. In order to adapt to the increase of air temperature, the type of hot blast stove has developed from internal combustion to external combustion with the separation of combustion chamber and regenerator. In design, the materials used for different wind temperatures on the top are roughly divided into: when the air supply temperature is not more than 900 ℃, multi clinker clay bricks are used for high temperature parts, the air supply temperature is 1000 ℃ or slightly higher than 1000 ℃, 48% high alumina bricks are used for clay bricks or Al2O3, high alumina bricks are used for air supply temperature higher than 1000 ℃ (the Al2O3 content is 55%), the air supply temperature is more than 1200 ℃, and 70% high alumina bricks are used for air temperature Use silica brick when temperature is higher than 1250 ℃. The temperature of furnace wall, vault and upper part of regenerator is 200-300 ℃ higher than that of normal air supply. China built high alumina bricks on the upper part of the regenerator in the early 1960s. In the 1980s, the Japanese hot blast furnace technology was adopted in the construction of large blast furnace in Baoshan Iron and steel works, and silicon bricks were used at the top and upper lattice bricks.

Project Indicators		RL-65	RL-55	RL-48
AL2O3,%		≥ 65	≥ 55	≥ 48
Refractoriness,℃		≥ 1780	≥ 1760	≥ 1740
Apparent porosity %		≤ 22 （ 24 ）
Normal temperature compressive strength,MPa		≥ 50	≥ 45	≥ 40
0.2MPa load softening start temperature ℃		≥ 1500	≥ 1470	≥ 1420
Change rate of reheating line,%	1500℃×2h	+0.1 ～ -0.4	+0.1 ～ -0.4	/
	1450℃×2h	/		+0.1 ～ -0.4
Thermal shock stability, (1100 ℃ water cooling) times		(roof and wall brick) ≥ 6
Note: the value in brackets is the index of checker brick in regenerator