Tundish and its role in Continuous Casting Sep28

Tundish and its role in Continuous Casting...

Tundish and its role in Continuous Casting Continuous casting of steel is a widely used process and an important step in the production of steel. The share of continuously cast steel around the world has increased significantly in the last 35 years or so. Presently this share is above 95 percent. However, concurrent with this increase in production levels, there are stringent quality requirements that have become crucial in the face of progressively increasing throughputs of continuous casting machines and larger dimensions of the cast products. In the process of continuous casting, to transfer liquid steel from a steel teeming ladle to the mould, an intermediate vessel, called a tundish, is used. A tundish is a rectangular big end up refractory lined open container which may have a refractory lined cover on the top. The tundish bottom has one or more holes with slide gate(s) or stopper rod(s) for controlling the metal flow. It is used to feed liquid steel into the copper moulds of a continuous casting machine, so as to avoid splashing and give a smoother flow. The tundish being a reservoir of the liquid steel ensures the feed of the liquid steel to the continuous casting machine during the change of steel ladles, thus acting as a buffer of liquid steel. It smoothens out flow, regulates steel feed to the mould and cleans the metal. Metallic remains left inside a tundish are known as tundish skulls and need to be removed, typically by mechanical means (scraping, cutting). Scrap recovered in this way is ordinarily recycled in the steelmaking process. The tundish is required to deliver the liquid steel to the moulds evenly and at a designed throughput rate and temperature without causing contamination by inclusions. The number of moulds is normally 1 to 2...