As a key refractory material for billet continuous casting, the sizing tundish nozzle plays the role of controlling the even and stable flow of molten steel from the tundish to the mold, stabilizing the drawing speed, and maintaining the height of the liquid level in the mold, thereby ensuring the quality of the billet. To improve continuous casting efficiency, its quality directly affects the length of continuous casting time.
The structural design of the sizing nozzle is divided into upper and lower parts. The upper part is approximately streamlined. When the molten steel flows to the mold through the sizing nozzle, the approximate streamline structure design can ensure that the resistance generated by the molten steel and the nozzle working surface (flow steel surface) is small. The effect of stabilizing the flow of molten steel to the mold, there will be no leakage, and this structural design has little disturbance to molten steel, which can reduce and improve the erosion resistance of the nozzle products to a certain extent, thereby extending the nozzle's resistance. Use time to improve the service life of the nozzle; the longer part of the lower part is the sizing section, this design can ensure that the molten steel flows into the mold evenly and stably from the tundish. During the casting process, the inner diameter of the sizing nozzle for the tundish should remain basically unchanged, because the sizing nozzle plays a role in controlling the flow of molten steel. Once its inner diameter expands too much, it will cause continuous casting to fail. Affect the production efficiency of continuous casting, so the erosion resistance and erosion resistance of the sizing nozzle should be high.
Classification of sizing nozzles:
With the reform and improvement of continuous casting technology and functional refractories, the zirconium sizing nozzle is most commonly used in China. According to the different content of zirconia in the sizing nozzle, zirconium sizing nozzles can be divided into two types: ordinary sizing nozzles and zirconia sizing nozzles
Due to the different production processes, ordinary sizing nozzles can be divided into four homogeneous sizing nozzles, direct compound sizing nozzles, vibration forming sizing nozzles and inlaid sizing nozzles.