From steel ladle to tundish, there are refractories for molten steel flow control, These refractories include well block, upper nozzle/ladle nozzle, upper slide gate plate, lower slide gate plate, lower nozzle/collector nozzle, and sometimes there is also ladle shroud/long nozzle.
Well block for the slide gate set is installed onto the bottom of the steel ladle. Upper nozzle which is also called ladle nozzle is put inside the well block. When molten steel flows through the nozzle at high temperature, chemical corrosion and scouring of molten steel & slag, as well as mechanical damage during installation, require the nozzle to have a long service life and be resistant to erosion and scouring of molten steel and slag. The service life of the nozzle is related to factors such as steel grade, excess steel amount and casting time.
The collector nozzle is mainly used to control the Flow and flow rate of molten steel. It is required to have good erosion resistance at high temperature, good thermal volume stability and a certain degree of self-fluxing. The damage factors of the collector nozzle include: corrosion and erosion of molten steel and slag; Cracking or fracture caused by sudden temperature change; melting loss caused by burning oxygen. Its material requires good corrosion resistance. For example, high aluminum and fused silica can be used for casting ordinary carbon steel; when casting steel with high Manganese, aluminum carbon, magnesium and other material can be used to improve the performance of the nozzle. To improve the thermal shock resistance, lower nozzles are covered in the iron sleeve to prevent cracking. Oxygen burning should be avoided as much as possible. The collector nozzle is made of high-aluminum, alumina-carbon and alumina -- zirconia -carbon, and its service life is once and 2-3 times respectively.
Slide gate plate
Types according to sliding method:
Reciprocating type
Spiral type
According to pieces per set: two layers type and three layers type
According to application: slide gate plate for steel ladles and slide gate plate for tundish
