Continuous casting is a widely used steelmaking process to continuously pour the molten steel into a cooled and solidified state, so that the steel is continuously output in a certain size of billet and will not solidify in the tundish. The continuous casting process includes the following three main processes, steelmaking, molding and cutting.
Steel making: the molten steel from the converter is de-sulfurized and dephosphorized by adding appropriate deoxidizing agent, and then sent to the tundish with the tundish car or by pumping.
Molding: Through purging, stirring and flow control, the molten steel is distributed in the tundish and evenly flows through the nozzle into the mould. During the steel pouring process, the temperature of the molten steel is controlled and the pressure of the nozzle is controlled to ensure that the molten steel volume is uniform and slow. At the same time, the inner wall of the mould is sprayed to ensure that the heat exchange of the mould is uniform and effective, so that the last solidification time and temperature are above the required value.
Cutting: After the steel is poured into the mould, the length of the ingot is determined according to the cycle of the continuous casting machine and the predetermined length, and then cut by a cut-off machine. The cut billet is supported by a belt conveyor and uniformly transported out of the continuous casting machine.
The continuous casting technology has the following advantages.
1. It has high unit production capacity, and the capacity per stamping machine and .mould is much larger than that of ordinary casting.
2. It can reduce labor intensity, save energy and reduce production cost. The solidification speed of the steel is higher, and the energy consumption is lower.
3. The control and automatic degree of the production process is high, the production efficiency is high and the safety is improved.
4. The product quality has been greatly improved. The continuous casting system of the new modern steel plant can ensure the chemical composition of the steel, the temperature of the steel and the surface quality of the steel billet. The surface roughness of the steel billet can reach up to Grade 2, and the internal structure is compact and uniform.
5. It can meet the production of various varieties and specifications, and reduce the production cost of mold steel.
The continuous casting technology has brought great convenience to the production of steel, and has made great contributions to the development of the steel industry. By using this technology, various shapes of plates, ribbed steels and steel bars can be quickly produced with high accuracy and low cost.
