Abstract：Lianyuan steel developed light LF refining technology for high-grade hot rolled coil relying on KR one-button desulfurization， accurately pre-deoxidation after BOF and automatic bottom-blowing at argon station. The stopper rod rising problem was resolved by adding aluminum one time at LF， controlling [O] content in liquid steel before adding aluminum between 40×10－6 and 100×10－6， soft blowing sustaining 8 mins after adding aluminum. The T.Fe content in top slag in ladle at LF beginning could be controlled below 3% by top slag modified and accurately pre-deoxidation during tapping. This work ensures that the steel purity did not getting worse through light LF refining process. The sulfur content of liquid steel in tundish through light LF refining was less than that through traditional LF refining process. The sulfur content was 0.003 5% and 0.004 6%. Through this technology， not only the cost was reduced significantly but also the oxygen and nitrogen content was 10×10－6 lower， inclusion was less and fatigue property was better than those of traditional process.
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