Introduction of chrome nozzle filler sand and how it causes automatic opening

Made from chromite sand and additives, chrome nozzle filler sand has the advantages of high specific gravity, good fluidity, high melting point, not excessively sintered, etc. When the added chromite sand is over 60%, chromite will be in continuous distribution, which can help forming continuous sintered layers.

Under high temperature, the FeO in chromite sand will react and dehydrate, producing quadratic spinel, then the volume of sintered layer will change and crack, when the slide gate plate is opened, the unsintered nozzle filler sand in the lower part of nozzle will flow out very fast, the cracks in the sintered layer will expand, due to the static pressure of molten steel, the sintered layer will be totally broken. All the above steps finally lead to automatic opening.