Principle: The working principle of the slag plug is basically the same as that of the slag ball. In the later stage of the tapping port, the slag plug guide rod portion is inserted into the tapping port by using a mechanical arm, and the hemisphere is partially suspended at the interface between the molten steel and the slag liquid. When the molten steel is exhausted, the hemispherical slag plug blocks the tapping port to achieve suppression. The role of molten steel eddy current and slag blocking.
Features: The slag plug shape is divided into upper and lower parts, the upper part is similar to the hemisphere, with 3 grooves, and the lower part is the guide rod with smaller diameter. The slag plug is made of cast iron as the core, and is made of high-alumina refractory concrete and refractory fine powder as refractory concrete or magnesia refractory mud, which is formed by vibration molding or friction press.
Principle: At the end of tapping, the slag ball is dropped over the taphole using a mechanical arm, and the slag ball is dropped at the taphole to block the slag from flowing into the ladle.
Features: The shape of the slag ball is spherical, and the center is generally made of cast iron block, raw iron chip press block, small scrap steel billet and other materials. The outer reinforced refractory material can be made of high aluminum castable or magnesium castable. The density is generally between 4.2 and 4.5 g/cm3. At present, most steel mills in China use this method.
Effect: The slag ball method is simple in operation, simple in structure and low in cost, which is beneficial to reduce the consumption of raw materials. However, after the tapping port is eroded by molten steel, the hole diameter is continuously increased, the diameter of the slag ball is constant, and the slag blocking efficiency is gradually reduced. In addition, the slag ball must be put in when the amount of tapping reaches 1/2-2/3, and the rate of the slag ball is relatively high.