Title: A First Attempt to Implement a Swirl Blade in Production of Ingots
Abstract: Plant trials were carried out to test if it would be possible to place a ceramic swirl blade in the runner channel during filling of ingots. The initial experiments showed that no production disturbances were found. More specifically, no problems with unusual refractory wear or cracks in the refractory were found. Thus, it was concluded that the use of swirl blade has a potential in the future to be used to influence the initial filling conditions. Also, mathematical modeling was done in order to illustrate how it was possible to improve the layout of the runner system in order to increase the potential for use of swirl for the current plant conditions. The results showed that the meniscus was not dampened as much when the swirl blade is positioned in a horizontal direction in the runner channel compared to the results of a previous physical modeling study where the swirl blade was placed in a vertical direction just before the steel entered the mold. However, if a horizontally positioned swirl blade is used in combination with an inlet with an angle of 15 degrees the hump height at the initial filling stage can be lowered from 100 to 58 mm compared to a case without a swirl blade. This illustrates the potential to apply mold powder closer to the bottom, without risking reoxidation due to reactions with steel and mold powder.