What Is Tundish In Steel Industry By Kassem Mohamad Ajami?

What Is Tundish In Steel Industry By Kassem Mohamad Ajami? Kassem Mohamad Ajami says continuous casting of steel is a widely used process and is an important step in the production of steel. The share of continuously cast steel around the world has increased significantly since the introduction of the continuous casting process in 1950s. Presently this share is around 97 %. However, concurrent with this increase in the use of the process, there are stringent quality requirements which have become crucial in the face of progressively increasing throughputs of the continuous casting machines and larger dimensions of the cast products. In the continuous casting process, for the transfer of the liquid steel from a steel teeming ladle to the mold, an intermediate vessel, called a tundish, is used. The tundish is located above the mold, to receive the liquid steel from steel teeming ladle and to feed it to the mold at a regulated rate. It is needed to deliver the liquid steel to the molds evenly and at a designed throughput rate and temperature without causing contamination by inclusions. The liquid steel flows out of the ladle into the tundish which links the discontinuous secondary metallurgy processes with the continuous casting process. Tundish smoothens out flow, regulates steel feed to the mold 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 performs the important role of serving as a buffer vessel between the batch ladle process and the continuous casting process. It is also the last metallurgical vessel before continuous casting and hence, it plays an essential role in delivering steel with the correct composition, temperature, and quality. This function has become increasingly important over the last few decades with increasingly stringent requirements for the quality of the steel products. The contributions of the tundish in the process of continuous casting are (i) to reach stability of the liquid steel streams entering the casting mold, and in turn, to achieve a constant casting speed, (ii) to cast a sequence of heats, (iii) to change over the empty steel teeming ladle for a full steel teeming ladle without interrupting the flow of liquid steel in the molds, (iv) to make a mixed grade with steel from two different grades of two different heats, if needed, (v) to provide possibility to prevent inclusions and slag from entering tundish and thus slipping into mold, (vi) to enhance oxide inclusion separation, (vii) to maintain a steady liquid steel height above the nozzles to the molds, thereby keeping steel flow constant and hence casting speed constant as well, and (viii) to provide more stable stream patterns to the molds. Detailed information about the tundish is provided in this blog post by Kassem Mohamad Ajami The main function of the tundish is to be a steel reservoir between the steel teeming ladle and the mold, and in the case of multi-strand continuous casting machines to distribute the liquid steel into the different molds. Tundish 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. Since the tundish act as a reservoir of liquid steel during the period of ladle change periods and since it continues to supply liquid steel to the molds when the incoming liquid steel has stopped due to ladle change, it makes the sequence casting by a number of ladles feasible. Tundish is a refractory-lined vessel with a variety of possible geometries. It is a rectangular big end up refractory lined open container which can have a refractory lined cover on the top. There are several types and shapes of tundish. Tundishes are normally of elongated and geometrically simple shape. The shape of the tundish is typically rectangular, but delta, and ‘T’ shapes are also sometimes used. One common tundish design for multi-strands billet and bloom continuous casting machines is a

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