The Use Of Silica Brick In The Hot Stove

Silica brick is widely used in the hot stove of large blast furnaces. The high temperature zone of the hot stove include the crown and the upper part of the checker work. The temperature in the region is stablized at a high temperature section without big fluctuations. It is mainly constructed with silica bricks. 

The silica brick used in the hot stove is mainly composed of tridymite. It has the following features: 

1) it should have stable volume and low creep rate at high temperature and can be used for one or even two blast furnace campaign. 

2) It should have good thermal shock resistance above 600℃ and can be adapted to the change of the hot stove well and maintain the integrity of the brick and masonry. 

3) It should have good chemical resistance than fire clay brick and high alumina brick and the basic substances in the gas, smoke and dust can only form a layer of glass phase on the surface and will not peel off. 

4) Since the thermal conductivity of the silica brick is bigger than that of the fire clay brick and high alumina brick, it can store and release heat in a short time. 

 

Currently, with the development of the steel making technology, the hot stove tends to have higher air temperature and higher capacity. The air temperature has been improved to 1350℃. Due to the imporvement of the temperature, the requiremnets on the silica brick has been more serious.