What is Mould Tundish?
The intermediate vessel used to transfer the molten steel from the pouring ladle to the casting machine mold is called tundish.
It is in the form of a container with refractory applied, and at the bottom there are barriers and dams to control the flow of molten steel and filter out impurities. The configuration can be changed according to the capacity of the tundish, and the flow of the molten steel and the residence time can be changed according to the configuration to control the flow rate to the mold.
During ladle change, the tundish acts as a reservoir for molten steel and continuously injects molten steel into the mold. Eventually, the molten steel received from the ladle stays in the tundish and controls the flow, showing that it plays an important role in connecting the discontinuous process to the continuous casting process.
How does Tundish work?
The molten steel flows from the pouring ladle into the tundish inlet, and the molten steel flows along the barriers and dams, filtering out impurities and exiting the outlet. A tundish containing molten steel with few impurities can omit barriers and dams.
※ Detailed specification of Mould water jacket can be adjusted according to customer's requirement
Tundish Design Considerations
What kind of molten steel will be contained?
Depending on the molten steel, the temperature setting and the refractory have to be different. Normally, the temperature of molten steel is from 1100 ° C to 1500 ° C. If the molten steel changes, it can be used after the refractory is replaced.
Durability is more important than anything else. Robust design such as thickness and material selection to hold high temperature molten steel is the first priority, and internal quality needs to be secured by non-destructive inspection. Butt joints are to be subjected to UT inspection and to check for internal cracks by post-weld stress relief (VSR) and nondestructive testing (MT).
Desired output and line
The amount of tundish is determined by the amount of production. In addition, the tundish outlet hole is the same quantity and spacing as the production line. At this time, the pitch tolerance is ± 0.5mm and the precision work should be done with the accumulated tolerance ± 2.0mm.
Flow of molten steel
The main use of tundish is to filter out the impurities in molten steel and to control the flow rate. At this time, the flow must be identified and the dam and barrier properly configured. The size of the tundice can be determined and the residence time of the molten steel can be determined by how the dams and barriers are constructed. Matching the flow of molten steel with the withdrawal speed is a key control technique for continuous casting.
Delivery Performance of Tundish
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