Blast furnace hot-blast stoves are widely used in iron and steel industry because they can provide hot blast with higher temperature and stronger blast pressure. With the relative rise of cost, the zinc-recovery hot-blast stove has been gradually replaced by the iron-making hot-blast stove. The iron-making hot-blast stove is an important heat energy device in iron and steel industry, so it has become the focus of related research.
The development process of blast furnace hot-blast stoves can be divided into casting, fire grate, multi-frame and multi-cylinder blast furnace hot-blast stoves. The blasting stoves used in iron and steel production process usually use hot-blast stoves as the heat energy source. The blower used for practicing of hot blast was made of cast iron or cast steel. It adopts the form of manual blast or mechanical blast. Today large blast furnace hot-blast stoves not only require a high temperature of hot blast, but also need to be able to adjust the blast capacity according to the different requirements of different processes.
The main body of the blast furnace hot-blast stoves need strong corrosion resistance and resistance to pressure. The current blast furnace hot-blast stoves are generally multi-frames and multi-cylinders. The shell of the main body is usually made of low-alloy steel plate with high strength and good corrosion resistance. The top of the hot-blast stoves usually adopts pre-welded steel plate engineering structure, while the middle and lower part adopts cast-in-place structure, and the joint use of steel plate engineering and cast-in-place structure greatly increases the strength and stiffness.
The construction of the multilayer pre-welding of the blast furnace hot-blast stove is of great significance. Through the analysis of the structure, the heat resistant steel plate is pre-welded, and the high temperature seal welding is used to ensure the tightness of the shell. The multilayered pre-welding structure can also reduce the number of fire door supports and brackets, reduce the thermal expansion stress of the shell and increase its integrity.
The interior of the blast furnace hot-blast stove is equipped with ceramic refractory bricks, which can withstand the high temperature of hot blast and radiant heat; and the corner of the hot-blast stove is also filled with insulation bricks, which can prevent the heat from being transmitted back and forth along the wall, and improve the thermal efficiency of the furnace.
In order to ensure the strength and integrity of the blast furnace hot-blast stove, the wall in the interior of the hot-blast stove is equipped with enough support bars and rib plates. The support bars are usually made of stainless steel, and the rib plates are made of stainless steel or carbon steel, depending on the requirements of the furnace. At the same time, the hot-blast stove is equipped with a circulating fan, which can make the hot blast generated at the lower part of the furnace pass through the wall of the furnace and enter the upper part, so as to make the temperature distribution in the furnace more uniform.
Therefore, blast furnace hot-blast stoves are an indispensable heat energy device in iron and steel industry, and its high temperature, strong pressure and good circulation can provide ideal hot blast for iron and steel industry.
