Sep. 17, 2018
The damage of the insulating refractory brick for the hot blast stove is: for the general internal combustion type hot blast stove, cracking is very likely to occur in the partition wall part, cracking and collapse etc are likely to occur in the dome. The masonry of two chamber vault and joints of pipes of external combustion type hot blast stove is prone to cracking and falling off.The damage of top fired hot blast stove is mainly at the vault and the nozzle.
The cause of damage in different parts of hot blast stove is different. So it is complicated to analyze in detail the causes of damage and the mechanism failure of the refractory masonry in each part of the hot blast stove. We hereby generally summarize the causes of damage as following.
High temperature thermal stress. The temperature difference between the inner and outer surfaces of the hot blast furnace wall insulating refractory brick is very large, and a large thermal stress is generated, that is, the inner side of the brick lining is subjected to a large compressive stress, and the outer side is subjected to a large tensile stress. Moreover, the expansion force and the load-bearing force of the refractory masonry are mainly concentrated on the inner surface of the inner lining of the hot blast stove, and the furnace changing operation further changes the cold and heat changes on the inner side of the insulating refractory brick lining. Under the influence of these factors, the inner side of the refractory masonry first cracks, which causes looseness and shedding, and in severe cases, the dome collapses and the partition wall falls.
This issue we mainly introduced damage to insulating refractory bricks of hot blast furnace caused by high temperature stress. Hope this can bring help to furnace builders. Next issue we will continue to introduce damage to insulating refractory bricks of hot blast furnace caused by chemical erosion and mechanical scouring and friction. Please stay tuned.