Global technology company ABB recently launched its Tundish EMS (electromagnetic stirring solution) to enable steelmakers to overcome the limited ability of the tundish vessel in controlling the flow of molten metal, and therefore steel quality and temperature.

The tundish is an intermediate vessel between the steel teeming ladle and the mould in continuous casting. Located above the mould, the tundish feeds the received steel evenly at a designed throughput rate and temperature without causing contamination by inclusions. The tundish thus is a buffer vessel between the batch ladle process and continuous casting.

Continuous casting (Tundish and Mould) 1. Ladle 2. Tundish 3. Mould 4. Plasma torch 5. Stopper 6. Straight zone. Credit: Tosaka, CC BY 3.0 , via Wikimedia Commons

Tundish EMS is placed on the outside of the tundish and uses non-contact electromagnetic stirring technology to generate an electromagnetic field that creates a stirring effect in the bath melt. This continuous stirring significantly increases mixing zone volume for virtually the entire tundish, with higher flow speeds, elimination of dead zones and homogenization of temperature.

Adoption of this electromagnetic stirring technology will be particularly important for steelmakers with multiple casting strands coming from one tundish. It will mean greater removal of inclusions, resulting in smoother, cleaner steel and reductions in nozzle clogging.

By creating a stirring flow throughout the entire tundish melt bath, Tundish EMS delivers rapid homogenization of temperature and chemical composition that results in better quality steel, more uniform and repeatable casting conditions across multiple strands and overall improved quality, productivity and profitability in billet and bloom casting and metal powder production.

The new Tundish EMS is a result of ABB’s know-how in stirrer design and unrivalled process insight gained from thousands of installations as well as track record in collaborative product development. It allows steelmakers to overcome a challenge that tundish furniture has not yet been able to solve. As well as increasing quality, productivity and profitability, Tundish EMS uses non-contact electromagnetic stirring technology which extends lifespan and means almost no maintenance is required.

—Zaeim Mehraban, Global Sales Manager, Metallurgy Products at ABB

Tundish EMS offers several new functionalities including flexibility in stirring force and direction and the ability to stir and control the flow field in the whole melt volume of the tundish. This means that steelmakers no longer have to rely solely on the limited ability of tundish furnishings for control of molten metal flow, where often significant dead zones lead to temperature variations and where smaller inclusions or inclusion clusters cannot be removed. A variety of Tundish EMS installation configurations are available for most tundish types.

Tundish EMS enhances quality, productivity and profitabilty in a number of ways. As well as improving non-metallic inclusion removal and overall steel cleanliness, it also provides temperature homogenization and stability throughout the entire tundish melt bath, reducing superheat and enhancing uniformity of temperature across various strands. Overall process repeatability and reliability is improved and costs are reduced by lowered consumption of tundish furniture such as dam, weir and baffle materials.