Ladle nozzle filling compound (NFC) is an indispensable refractory material for
EAF tapping.
Ladle nozzle filling sand is mainly using fluorite from Henan and fused magnesia from Dashiqiao in Liaoning as main raw materials, and Hubei Yichang carbon materials as additives. According to the combination of specific particle size and weight percentage, NFC is prepared by mixing. After trial, it is proved that NFC has good dispersion fluidity, high refractoriness, no sintering, no clogging, and tapping rate. 100%, use temperature ≥1750℃, no chemical reaction with molten steel and alloy components, no variability in storage quality, can meet steelmaking process requirements, is the most ideal
refractory material for EAF steelmaking.
The characteristics of NFC are as follows:
1) It is required to be able to sinter at a lower temperature to avoid accidents caused by the floating of NFC when molten steel is added;
2) It is required that the molten steel surface cannot be sintered too thick under high temperature and long-term smelting, in order to achieve automatic pouring, improve production efficiency, reduce molten steel pollution, reduce flue gas consumption, and improve production safety factor.
The ladle self-opening rate is related to the type and quality of drainage materials, pouring steel conditions,
ladle refractory materials, and the level of operation of workers.
