Abstract: The paper involved in intrduction of metallurgical process development for IF Steel in Shougang Jingtang. The key processes of IF steel include carbon, nitrogen content control and coil surface quality control (dealing with the inclusions and nozzle clogging). The key points for carbon control are decarburization in RH process, resistance to recarburization from the end of RH process to tundish, with which the actions are controlling the w(C)≤0.04 % before decarburization, decreasing the scrap addition in RH process, bottom argon blowing along with the decarburization, clean alloy charging, using carbon-free refractory, and so on. The key points for nitrogen control are denitrification in converter process, resistance to renitrification from the RH process to tundish. One of the main defects on surface of IF coil is “inclusion” kind defects. Some anti-inclusion actions usually include low oxygen content at end of converter process, deoxidation for ladle slag, w(Als)/w(Alt)＞0.94 in steel at end of refining process and tundish. After the metallurgical process development, the tundish component of carbon and nitrogen decrease with amount of 3.7×10-6 and 5.9×10-6, the degraded coil percent decreases from 2.3 % to 1.0 %-1.5 %。

Key words: component control, nozzle clogging, alumina inclusion, argon blowing